FOOD 


AND  THB 


PRINCIPLES    OF    DIETETICS 


BY 

ROBERT  HUTCHISON,  M.D.  Edin.,  F.R.C.P. 

Physician  to  thk  London  Hospital  ;    Physician  with  Cmarcr  op  Out-Patiknts  to  tm 
Hospital  fok  Sick  Chilokkn,  Great  Ormond  Stkekt 

htrruom  or  '  Lbctures  on  Diseasbs  of  Chiloken,'  '  Patent  Foods  and  Patent  MsiuaNi 
'ArrUKD  PuvsioLocy,'  Joini-Author  op  'Clinical  Mbthods' 


WITH  PLATES   AND  DIAGRAMS 


FOURTH   EDITION 


NEW  YORK 

WILLIAM    WOOD    AND    COMPANY 

MDCCCCXVII 


UBBARV 


I»J& 


TO   THE 

STUDENTS   OF    THE    LONDON    HOSPITAL 

TO    WHOM    ITS    CONTENTS    WERE    FIRST    ADDRESSED, 

AND    BUT    FOR    WHOSE    ENCOURAGEMENT 

IT    WOULD    NOT    HAVE    APPEARED    IN    ITS    PRESENT    FORM, 

THIS   VOLUME    IS    DEDICATED 

BY 

THE   AUTHOR. 


3G9204 


PREFACE  TO  THE  FOURTH  EDITION 

In  this  edition  the  whole  book  has  been  thoroughly  revised,  and 

many  minor  alterations  and  additions  effected.     A  section  has  been 

included  on  the  subject  of  Vitamines.      The  prices  of  foodstuffs 

referred  to  are  those  which  obtained  before  the  war,  no  attempt 

having  been  made   to  substitute  for   these  the  present   abnormal 

and  fluctuating  prices,  which,  it  is   to  be  hoped,  will  only  be  of 

temporary  duration. 

R.  H. 

London,  May,  igiQ^ 


PREFACE   TO   THE   FIRST   EDITION 

The  contents  of  this  book  were  first  addressed  to  the  students  of 
the  London  Hospital  in  the  form  of  a  course  of  lectures  about  a 
year  and  a  half  ago.  The  very  gratifying  reception  accorded  to 
these  lectures  and  the  almost  total  neglect  of  the  subject  of  dietetics 
in  ordinary  medical  education  have  induced  the  author  to  publish 
them  in  their  present  form. 

While  the  book  has  been  specially  designed  to  meet  the  require- 
ments of  students  and  practitioners  of  medicine,  it  is  hoped  that  it 
may  also  prove  intelligible  and  interesting  to  anyone  desiring  to 
acquire  some  knowledge  of  foods  and  the  difficult  problems,  of 
nutrition. 

In  recasting  the  lectures  for  publication  a  large  amount  of  addi- 
tional material  has  been  used,  and  no  pains  have  been  spared  to 
make  the  book  fully  representative  of  the  present  state  of  our  know- 
ledge on  the  subject  of  which  it  treats.  A  considerable  amount  of 
space  has  been  devoted  to  the  patent  and  proprietary  foods,  and  an 
effort  has  been  made  to  deal  fairly  and  honestly  with  their  merits. 
The  great  number  and  variety  of  these  now  offered  for  sale  makes 
this  specially  necessary. 

As  far  as  possible  original  papers  have  always  been  consulted, 
and  references  to  these  will  be  found  in  the  footnotes ;  but  if,  as  is 
only  too  probable,  some  important  publications  have  been  over- 
looked, the  vast  extent  of  the  literature  of  the  subject  must  be 
taken  as  the  author's  excuse. 

The  author  feels  also  that  he  is  under  a  great  obligation  to  the 


X  PREFACE  TO  THE  FIRST  EDITION 

many  able  systematic  writers  on  the  subject  who  have  preceded 
him,  both  in  this  country  and  on  the  Continent,  and  whose  names 
are  too  well  known  to  require  special  mention  here.  He  would 
like,  however,  to  take  this  opportunity  of  expressing  his  special 
indebtedness  to  the  work  and  writings  of  Professor  Atwater  and  his 
colleagues  in  America,  who  have  done  so  much  in  recent  years  to 
advance  our  knowledge  on  the  principles  of  dietetics.  The  opening 
chapters,  especially,  of  the  present  book  owe  much  to  the  teaching 
of  the  American  school. 

To  Dr.  Leonard  Hill  and  the  writer's  other  colleagues  at  the 
London  Hospital  Medical  College  he  must  express  his  gratitude 
for  much  encouragement  and  useful  advice,  and  to  his  friends 
Dr.  J.  J.  R.  Macleod  and  Mr.  Robert  Tanner  he  is  indebted  for  the 
pains  which  they  have  bestowed  on  the  revision  of  the  proof-sheets. 

The  illustrations  have  been  drawn  by  Mr.  Danielsson  with  his 
usual  skill,  and  the  care  with  which  Mr.  Archibald  Clarke  has 
compiled  the  index  has  saved  the  author  much  labour. 

London,  October,  igoa. 


CONTENTS 

CHAPTER  I 

THE  NATURE,  KUTPvITIVE  CONSTITUENTS,  AND  RELATIVE  VALUES 

OF  FOODS 

PAGES 

Definition  of  the  term  '  food ' — Food  as  a  source  of  building  material,  heat 
and  energy — The  nutritive  constituents  of  food,  and  their  functions — 
The  relative  value  of  foods — Chemical,  physical,  physiological  and 
economic  standards — Mode  of  applying  these — The  Calorie — Digesti- 
bility and  '  absorbability '  of  foods — The  relative  cost  of  foods  judged 
as  sources  (i)  of  building  material,  (2)  of  energy — Vitamines  •        1-19 

CHAPTER  II 
THE  AMOUNT  OF  FOOD  REQUIRED  IN  HEALTH 

Methods  of  stating  the  amount  of  food  required— Amount  of  protein 
required  daily — Chittenden's  results — Amount  of  potential  energy  •> 
required  in  diet — Standard  dietaries — Empirical  and  physiological 
method  of  constructing  these — Number  of  Calories  and  amount  of  each 
nutritive  constituent  required  daily — Nutritive  ratio  in  foods— Necessity 
for  a  mixed  diet — Standard  diets — Actual  diets  of  various  persons  in 
different  conditions  of  life        ......        20-34 

CHAPTER  III 

ON  THE  INFLUENCE  OF  VARIOUS  CONDITIONS  UPON  THE  AMOUNT 
OF  FOOD  REQUIRED 

Influence  of  work — Muscular  work — The  diet  of  training — Mental  work — 
Influence  of  rest — Influence  of  build  and  shape— Importance  of  surface- 
area — Influence  of  age — Requirements  of  childhood  and  old  age — In- 
fluence of  sex — Requirements  of  women — Influence  of  climate  and 
season — Influence  of  personal  peculiarity — Over  and  under  feeding         35*57 

CHAPTER  IV 

ANIMAL    FOODS 

Meat — Physical  structure — Chemical  composition — Effects  of  cooking  on 
structure  and  composition— Digestibility  and  absorption  of  meat — 
Nutritive  value  and  economy — Use  of  horseflesh  and  the  flesh  of  dis- 
eased animals — -'  OflaJ  ' — Liver  and  kidneys — The  heart — Blood — Lungs 
— Sweetbread  —  Tripe  —  Brain  —  Comparative  absorption  of  these  — 
Potted  meats — Sausages  -  .  .  .  .  ,         58.75 

xi 


xii  CONTENTS 

CHAPTER  V 
JELLIES  — FISH 

rAGSl 

Gelatin — Isinglass — Sources — Chemical  properties,  digestibility  and  nutri 
tive  and  economic  value  of  gelatin  and  its  preparations — Fish — Chemical 
composition  —  Fat  and  lean  fish  —  Digestibility  and  nutritive  and 
economic  value  of  fish — Caviare — Milt— Marvis — Lobster  and  crab — 
Oysters  and  other  shell-fish — Turtle — Frogs  -  -  .  -        76-S9 

CHAPTER  VI 

SOUPS,  BEEF-EXTEACTS.  BEEF-JUICES,  BEEF-TEA,  AND  BEEF- 
POWDERS 

Composition  of  soups — Their  nutritive  value — Clear  versus  thick  soup — Beef- 
extracts — History  of  Liebig's  extract — Its  chemical  composition — Nature 
and  physiological  action  of  the  extractives  of  meat — Value  of  Liebig's 
extract — Bovril  and  kindred  preparations — Their  claim  to  be  regarded 
as  foods — Beef-juices — Mode  of  preparation— Home-made  beef-juice — 
Comparison  of  the  patent  preparations  with  this — Nutritive  value  of 
beef-juices — Egg-white  mixture  as  a  substitute — Leube-Rosenthal's 
Meat  Solution — Beef-tea — How  to  make  it — Its  composition  and  uses — 
Exaggerated  estimate  of  the  value  of  beef-tea—'  Whole  beef-tea ' — 
Beef-powders — Pemmican — Beef-meal — Somatose,  etc. — Uses  of  beef- 
powders — Conclusions-  ......      90-109 

CHAPTER  VII 

MILK 

Protein=;  Sugar — Fat,  mineral  matter,  and  water  of  milk — General  com- 
position of  cow's  milk— Variability  of  this— Necessity  for  a  standard  of 
composition — Clotting  and  curdling  of  milk  -Effects of  heat — SteriHza- 
tion  and  pasteurization  of  milk -Methods  for  permanent  preservation 
— Digestibility— Methods  of  improving  this — Absorption  of  raw  and 
boiled  milk — Milk  as  an  intestinal  antiseptic— Nutritive  value  of  milk- 
Not  a  perfect  food — Reasons  for  this  opinion  — Economic  value  of  milk 
— Skim  milk  as  a  cheap  source  of  protein  —Milk  as  a  food  in  disease- 
Milk  '  cures  '    ..-.--..     110-131 

CHAPTER  VIII 

FOODS  DERIVED  FROM  MILK 

Whey — Mode  of  preparation — Composition — Food  value — '  "Whey  core ' — 
Cream— Proportion  of  fat — Devonshire  cream — Value  of  cream  as  a 
source  of  fuel — Its  cost — Butter — Preservation— Composition— Digesti- 
bility and  nutritive  value — Margarine — History  and  method  of  manu- 
facture—Comparison with  butter — Butter  versus  jam — Butter-milk — 
Koumiss  and  kephir— Mode  of  preparation— Composition  and  proper- 
ties of  these- Ca-sein  preparations — Protene  Flour — Sanose— Nutruse 
— Eucasin— Plasraon — Advantages  of  casein  as  a  source  of  protein — 
Uses  of  these  substances  ....•»    132-145 

CHAPTER  IX 

'  CHEESE,  EGGS,  AND  EGG  SUBSTITUTES 

Varieties  of  cheese — Composition — Digestibility — Nutritive  value — Eggs — 
The  egg  regarded  as  an  undeveloped  chick — Composition  of  shell, 
white  and  yolk— Digestibility  and  absorption  of  eggs— Patent  egg 
preparations  (Ovo,  etc.) — Custard-powders    -  -  -  -    146-159 


CONTENTS  xiii 


CHAPTER  X 
VEGETABLE  FOODS 

PACKS 

Chemical  characteristics  of  vegetable  foods  as  a  class — Starch,  cellulose, 
and  other  constituents  of  vegetables — Bulkiness  of  vegetable  foods 
and  methods  of  overcoming  it — Mineral  constituents— Digestibility  of 
vegetable  foods  in  the  stomach  and  intestine— DifiBculties  arising  from 
their  bulk  and  richness  in  cellulose — Absorption  of  the  different 
chemical  constituents  of  vegetable  foods — Proteins  not  well  absorbed — 
Reasons  for  this — Nutritive  value  of  vegetable  food — Pros  and  cons  of 
vegetauianism — Disadvantages  of  a  purely  vegetable  diet — Different 
methods  of  supplementing  the  deficiency  in  protein— Relative  economy 
of  animal  and  vegetable  foods — Nature's  food  cycle — Cost  of  cooking — 
Summary  ..--.--.     160-186 

CHAPTER  XI 

THE  CEREALS  :   WHEAT— BREAD 

Classification  of  vegetable  foods — General  characteristics  and  composition 
of  the  cereals — Wheat — Structure  and  composition  of  the  wheat  grain — 
Milling — Flours — Hovis  and  Frame  Food  processes — Bread — Leavened 
bread — Chemistry  of  baking — Aerated  bread  —  Baking-powders — 
Characters  of  a  good  loaf— Chemical  composition  of  bread — ^Whole- 
meal  versus  white  bread — Vienna,  brown,  germ  and  malted  bread — 
Patent  breads — Staling  of  bread — Effects  of  heat  on  bread — Biscuits 
—Rusks-  •  -  -  -  -  •  -  -    187.207 

CHAPTER  XII 

BREAD  {coHtinued)—OTEER  CEREALS 

Digestion  of  bread — Length  of  stay  in  stomach — Absorption  of  bread — 
Reasons  for  defective  absorption  of  proteins — Absorption  of  wholemeal 
bread — Cellulose  as  a  cause  of  difficulty — Nutritive  value  of  bread — 
Method  of  increasing  the  percentage  of  protein — Relative  nutritive 
value  of  wholemeal  and  white  bread — Cheapness  of  bread  as  a  food — 
Other  wheat  preparations  (semolina,  macaroni,  etc.) — Other  cereals — 
Oats — Maize — Barley — Rye — Rice — Millet  and  buckwheat — Composi- 
tion, preparations,  digestibility,  and  nutritive  value  of  these  -    208-230 


CHAPTER  XIII 

THE  PULSES— ROOTS  AND  TUBERS 

General  composition  of  the  pulses — Their  digestibility,  absorption  and 
nutritive  value — The  pea,  bean,  and  lentil — Revalenta — The  soy  bean 
— The  peanut  and  butter  bean — Roots  and  tubers — General  composi- 
tion, digestibility,  and  nutritive  value — Potatoes  :  composition,  etc. — 
Their  place  in  the  diet — The  sweet  potato  and  yam — Turnips — Carrots 
— Beetroots — Parsnips — Jerusalem  artichokes  and  onions — Tapioca, 
sago,  and  arrowroot      ...----      231-247 

CHAPTER  XIV 

VEGETABLES— FRUITS— NUTS— FUNGI— ALGiE  AND  LICHENS 

Green  vegetables — Composition,  digestibility,  and  nutritive  value  — Fruits — 
General  composition — Sugars  of  fruits — Mineral  constituents — Flavour 
^-Effects  of  cooking — Digestibility  and  nutritive  value — 'Food  fruits' 


CONTENTS 

fAGKS 

and  '  flavour  fruits  * — Grapes — The  '  grape  cure  — The  banana— The 
date,  raisin,  and  fig — Nuts — Composition — Nut  butters — DigestibiHty 
and  nutritive  value  of  nuts — Fromm's  Extract — The  chestnut  aiid 
almond — Fungi — Mushrooms  versus  toadstools — Edible  British  fungi — 
Chemical  composition  of  fungi — Their  digestibility,  absorption,  and 
nutritive  value — Algae — Irish  moss — Lichens — Iceland  moss  •     248-269 


CHAPTER  XV 

SUGAR,  SPICES,  AND  CONDIMENTS 

The  sucroses  and  glucoses — Cane-sugar — History,  composition,  and  refining 
— Beet-sugar — Maple-sugar — Maltose  and  lactose^Effects  of  heat  on 
sugar — Treacle,  molasses,  and  syrup — The  glucoses — Dextrose — Laevu- 
lose — Invert  sugar — Honey — Sweetmeats — Toflee — Chocolate — Jams — 
Digestion  of  sugar — Effects  on  the  stomach — Fermentation — Supposed 
effects  on  the  teeth— Assimilation  of  sugars — Alimentary  glycosuria — 
Nutritive  value  and  economy  of  sugar — Sugar  as  a  muscle  food — 
Spices  and  condiments — Their  role  in  the  diet — Mustard,  pepper,  and 
vinegar — Sugar  as  a  condiment — Saccaarui  and  duicin — ba.\.in  and 
porcherine        ...---.-     270-287 

CHAPTER  XVI 

MINERAL  CONSTITUENTS  OF  THE  FOOD 

Mineral  matter  as  building  material  for  the  body — Mineral  substances 
required — Are  they  sources  of-  energy  ? — Amount  of  them  required 
daily — Calcium — Magnesium — Iron — Sodium  and  potassium — Common 
salt — Influence  of  salt  on  digestion  and  metabolism — Phosphorus — The 
*  phosphates  '— Cerebos  salt — Oxalic  acid — Sulphur — Chlorine — Iodine 
—Fluorine  and  silica — Acidity  and  alkalinity  of  foods  •  -    288-299 


CHAPTER  XVII 

WATER  AND  MINERAL  WATERS 

Water  as  a  tissue-builder — Amount  of  it  consumed  daily — Effects  of  an 
increase  or  diminution  in  the  supply — Influence  of  water  on  digestion 
and  metabolism — Varieties  of  water — Water  as  a  source  of  infection — 
Sterilization  of  water — Aerated  waters — Classes  of  these — Natural 
mineral  waters — Uses  of  aerated  waters — Natural  versus  artificial 
mineral  waters  -  ..--...      300-312 


CHAPTER  XVIII 

TEA,  COFFEE,  AND  COCOA 

Tea:  History — Mode  of  manufacture — Varieties — Black  and  green  tea- 
Characters  of  China,  Indian  and  Ceylon  teas — How  to  judge  a  tea — 
Chemical  composition  of  tea — Composition  of  the  infusion — Propor- 
tion of  tajinic  acid  and  caffeine — How  to  make  tea.  Coffee :  History — 
Mode  of  manufacture — Varieties — Composition — Effects  of  roasting — 
Composition  of  the  infusion — '  French  coffee ' — Coffee-making.  Cocoa : 
History — Mode  of  manufacture — Varieties — Chemical  composition — 
Fat — Theobromine — Composition  of  commercial  cocoas — Chocolate. 
Influence  of  these  beverages  on  digestion — Di,;estion  and  absorption 
of  cocoa — Uses  of  tea,  coffee,  and  cocoa — Physiological  action  of 
caffeine — Food  value  of  cocoa-  .....      313-336 


CONTENTS  XV 

CHAPTER  XIX 
ALCOHOL 

rAOM 

Ethyl  alcohol — Local  effects  on  the  tissues — Effects  on  digestion — Absorption 

of  alcohol  by  the  stomach — Alcohol  as  a  stimulant — Action  on  the  heart 
and  circulation — influence  on  body  temperature — Influence  on  meta- 
bolism— Alcohol  as  a  protoplasm  poison  and  as  a  sparer  of  fat — Does  it 
spare  proteid  ? — Rate  of  its  combustion  in  the  tissues — Alcoholism  : 
acute  and  chronic — Amount  which  can  be  safely  consumed  daily — 
Influence  of  idiosyncrasy — Use  of  alcohol  in  health  and  disease      •     337-352 

CHAPTER  XX 

ALCOHOLIC  BEVERAGES :  SPIRITS  AND  MALT  LIQUORS 

Methods  of  stating  the  proportion  of  alcohol  present — Proof  spirit — Per- 
centage—Proportion of  alcohol  in  some  C(  liinion  beverages — Spirits — 
How  prepared — 'Silent  spirit'  —  Fusel-oil  —  Whisky  —  Definition  — 
Malt  whisky — Grain  whisky — Potheen— Brandy — Origin  and  manu- 
facture—  Cognac  —  Rum  —  Gin  —  Liqueurs  and  bitters  —  Action  of 
spirits  on  digestion  and  metabolism  —  Special  value  of  ethereal  by- 
products. Malt  liquors — Varieties  and  terminology — Beer — Brewing — 
Mild  and  bitter  ales — '  Substitute  beer' — Porter — German  beers — Com- 
position of  malt  liquors — Their  action  on  digestion — Their  use  as  foods 
— Cases  in  which  they  are  harmful — Non-alcoholic  beers     •  -      353-371 

CHAPTER  XXI 

ALCOHOLIC  BEVERAGES  {continued) :  WINES 

Definition  of  the  term  'wine  ' — Constituents  of  grape-juice — Fermentation 
— Changes  in  cask  and  in  bottle — Constituents  of  wine — Alcohols — 
Acids — Sugar — Ethers— Extractives — Glycerine — Varieties  of  wine^ 
•Natural'  and  'fortified'  wines — Claret — ^Burgundy — Hock — Hun- 
garian, Italian,  Californian  and  Australian  wines — Sherry — Port — 
Madeira — Marsala — Greek  wines — Champagne — Cider  and  perry  — 
Medicated  wines — Non-alcoholic  grape  wines — Influence  of  wines  on 
digestion — Action  of  wines  in  health  and  disease      .  •  •      372-393 

CHAPTER  XXII 

THE  COOKING  OF  FOODS 

Objects  of  cooking — Effects  of  heat  on  proteins,  carbohydrates,  and  fats- 
Cooking  of  meat — Ideal  to  be  aimed  at — Boiling — Roasting — Baking — 
Stewing — Cooking  of  fish — Frying — The  cooking  of  vegetable  foods— 
The  softening  of  cellulose — Use  of  acid  fermentation,  grinding  and 
boiling — Losses  in  cooking — The  taking  up  of  water  by  vegetable  foods 
— Composition  of  cooked  vegetable  foods — Slow  cooking — Its  advan- 
tages— Special  forms  of  apparatus  for  accomplishing  it — The  bain-marie 
and  its  modifications — The  Norwegian  cooker — Ede's  apparatus — Tlie 
Aladdin  Oven — Kanaka  cookery  .....     396-41 1 

CHAPTER  XXIII 

THE  DIGESTION  OF  FOOD  IN  HEALTH 

Digestion  in  the  mouth — Uses  of  saliva — Digestion  in  the  stomach — The 
stomach  as  a  reservoir — Meals— The  secretion  of  gastric  juice— Appetite 
and  hunger — Digestive  habits — Acidity  of  the  gastric  contents — Diges- 


xvi  CONTENTS 

rAGBC 
tion  of  starch  in  the  stomach — Morbid  gastric  sensations — Movements 
of  the  stomach — Functions  of  the  cardiac  and  pyloric  portions — The 
peristaltic  movements  of  the  stomach — Rate  of  digestion  of  different 
foods — Antiseptic  action  of  the  gastric  juice — The  temperature  of  foods 
— Absorptive  power  of  the  stomach — Digestion  and  absorption  in  the 
intestine — The  r61e  of  bacteria — The  faeces — Summary — Influence  of 
exercise  and  rest  on  digestion  ------     ^12-^33 

CHAPTER  XXIV 

THE  PRINCIPLES  OF  FEEDING  IN  INFANCY  AND  CHILDHOOD : 
HUMAN  MILK 

Physiological  requirements  in  the  diet  of  infancy — Necessity  for  protein  and 
fat — Human  milk :  its  composition  and  variations — Influence  of  (he 
period  of  suckling — Colostrum — Individual  differences — Influence  of 
mother's  diet  on  the  composition  of  the  milk — Influence  of  alcohol — 
Influence  of  frequency  of  suckling — Amount  of  milk  required  by  a  child 
daily — Importance  of  regular  feeding — Digestibility  of  human  milk — Its 
absorption  and  nutritive  value — Diet  of  infancy  contrasted  with  that  of 
the  adult  -----...     434-447 

CHAPTER  XXV 

THE  PRINCIPLES  OF  FEEDING   IN   INFANCY  AND   CHILDHOOD  {am- 
ixnued) :  SUBSTITUTES  FOR  HUMAN  MILK 

The  milk  of  other  animals — Relation  between  composition  of  milk  and  rate 
of  growth — Ass's  milk — Human  versus  cow's  milk — Quantitative  dif- 
ferences— Qualitative  differences  :  (i)  in  nitrogenous  matter ;  (2)  in  fat ; 
(3)  in  mineral  salts — Humanized  milk  a  chemical  impossibility — Com- 
parative digestibility  of  human  and  cow's  milk  in  the  stomach  and  in 
the  intestine — Infant  feeding  with  pure  cow's  milk — Modification  of 
cow's  milk :  (i)  by  mere  dilution ;  (2)  cream  mixtures  of  Meigs.  Rotch 
and  Biedert ;  (3)  Soxhlet's  sugar  method ;  (4)  humanized  milks, 
Fettmilch  ;  (5)  use  of  whey  as  a  diluent ;  (6)  Lehmann's  method — 
Milk  prescriptions — Sterilization — Summary  ...      448-460 

CHAPTER  XXVI 

THE  PRINCIPLES  OF  FEEDING  IN  INFANCY  AND  CHILDHOOD  (con- 
tinued) :  OTHER  SUBSTITUTES  FOR  HUMAN  MILK  (PEPTONIZED 
MILK,  CONDENSED  MILK,  PROPRIETARY  FOODS);  FEEDING  OF 
OLDER  CHILDREN 

Peptonized  milk — Fairchild's  peptogenic  milk-powder — Condensed  milk 

Method  of  manufacture  and  composition — Varieties — Sweetened  and 
unsweetened   whole    milks — Condensed    skim    milks — Digestibility   of 

condensed  milk — Its  nutritive  value  and  economy — Its  poverty  in  fat 

Humanized  condensed  milk — Condensed  milk  as  a  cause  of  scurvy 

Proprietary  foods— Defects— Composition — Uses — Summary  of  rules 
for  infant-feeding — Diet  after  weaning — Amount  of  each  nutritive 
ingredient  require!  at  different  ages — Importance  of  protein— Nutritive 
ratio  in  child  and  adult — Sources  of  protein,  fat,  carbohydrates  and 
mineral  matters — Beverages  for  children        -  •  •  .     461-478 

CHAPTER  XXVII 

THE  PRINCIPLES  OF  FEEDING  IN  DISEASE 

General  rules— Principles  of  diet  in  fever— Importance  of  carbohydrates- 
Fluid  diet — Use  of  milk  and  need  of  its  enrichment — Intervals  at  which 
food  should  be  given — Beverages  in  fevers — Use  of  alcohol— Diet  ia 


CONTENTS  xvii 

PAGES 

rheumatic  and  typhoid  fevers — Principles  of  diet  in  diabetes — Impor- 
tance of  fat — Quantity  of  carbohydrate  allowable — Classification  of 
cases — Sources  of  each  constituent — Special  articles  of  food  in  diabetes 
— Milk — '  Diabetic  milk  ' — Diabetic  breads — Special  forms  of  carbo- 
hydrate in  diabetes — Beverages — General  plans  of  diet  and  arrangement 
of  meals — Diet  in  complications — Gouty  glycosuria  -  -    479  501 

CHAPTER  XXVIII 

THE  PRINCIPLES  OF  FEEDING  IN  DISEASE  (continued) 

The  dietetic  treatment  of  obesity — General  physiological  considerations — 
Importance  of  the  different  constituents  of  the  food — Extent  of  limita- 
tion of  diet — Banting,  Oertel,  Ebstein,  Hirschfeld  and  Von  Noorder's 
systems — Relative  advantages  of  these — Particular  articles  of  food  in 
obesity — Arrangement  of  the  meals — Beverages  in  obesity — Advantages 
of  a  dry  diet — Fattening  diet — Food  in  convalescence,  phthisis  and 
neurasthenia — Dietetics  of  gout — Rheumatoid  arthritis — Diet  in  Gravel 
— Oxaluria— Dietetic  treatment  of  scurvy — Dietetic  treatment  of  in- 
fantile scurvy — Dietetic  treatment  of  rickets — Diet  in  disorders  of  the 
stomach — General  considerations — Gastric  ulcer — Acute  and  chronic 
gastritis — Dilatation  of  the  stomach — Functional  dyspepsias — Diet  in 
diseases  of  the  intestines — Diarrhoea — Sprue — Dysentery — Ulcerative 
and  muco-membranous  colitis — Constipation — Diet  in  diseases  of  the 
liver — Diet  in  cardiac  disease — Aneurysm — Diet  in  renal  disease — 
General  principles — Acute,  subacute  and  chronic  nephritis — Diet  in 
diseases  of  the  nervous  system — Diet  in  diseases  of  the  skin  -    502548 

CHAPTER  XXIX 
SOME  DIETETIC  '  CURES  "  AND  '  SYSTEMS  * 

Vegetarian  and  lacto-vegetarian  diet — Purin-free  diet — Dr.  Hare's  system — 
Exclusive  protein  diet — Zomotherapy — Salt-free  diet — Sour-milk  treat- 
ment ....-..-  549-558 

CHAPTER  XXX 

ARTIFICIAL  AND  PREDIGESTED  FOODS  AND  ARTIFICIAL  FEEDING 

Objects  of  artificial  foods — Limits  of  concentration  of  foods — Chemical  and 
physiological  considerations — Artificial  protein  foods :  (i)  Undigested, 
(a)  of  animal  origin,  (b)  of  vegetable  origin  ;  (2)  Peptonized — Artificial 
carbohydrate  foods — Malt  extracts — Their  use:  (i)  as  foods;  (2)  as 
digestive  agents — Honey  as  a  substitute — Value  of  milk-sugar — Artificial 
fatty  foods — Emulsions — Cod-liver  oil — Lipanin — Virol — Cremalto — 
Pancreatic  emulsion — Spermaceti — Cream,  butter,  nuts,  etc.,  as  sources 
of  fat — Toffee — Rectal  feeding — Absorptive  power  of  the  large  intestine 
— Constituents  of  eneraata — Possibility  of  a  reverse  peristalsis — Value 
of  adding  salt — Limits  of  usefulness  of  nutrient  enemata — Formulae — 
Technique — Nutrient  suppositories — Subcutaneous  feeding — Conditions 
to  be  fulfilled  by  a  food  suitable  for  subcutaneous  injection — Use  of 
proteins — Serum — Sugar — Fat — Limits  of  usefulness — Subcutaneous 
injection  of  yolk  of  egg — Gavage  auid  forced  feeding  •  •    559-580 

Index  .,.«.»»«•         581 


TABLE  OF  EQUIVALENTS 

In  a  book  on  dietetics  it  is  difi&cuit  to  avoid  the  use  of  several  different  standards 
of  measurement.  Thus,  the  Metric  System  is  usually  employed  in  the  scientific 
analyses  of  foods,  and  the  Imperial  System  in  the  measurement  of  foodstuffs  as 
purchased  in  this  country,  whilst  even  such  rough  domestic  standards  as  spoons 
and  cups  must  som.etimes  be  referred  to.  The  following  table  of  equivalents  of 
the  different  standards  may  therefore  be  found  of  use  : 


I  gramme 
I  kilogramme 


=      15 '4  grains. 

=  2  pounds  3  ounces. 


I  ounce 
I  pound 
I  fluid  ounce 
I  pint 


=      28-3  grammes. 

=  453"5        ., 

=         28  4  C.C. 

=  568    „ 


I  pint 

I  tumblerful 

I  breakfastcupful 

I teacupful 

I  claret  glassful 

I  sherry-glassful 

I  tablespoonful 


20  fluid  ounces. 
10 


(approx.). 


one-half  fluid  ounce. 


xVIH 


LIST   OF    ILLUSTRATIONS 


COLOURED  PLATES. 

I.  Fuel  Valde  of  One  Pound  or  some  Typical  Foods  Te  face        6 

II.  Percentage  of  Nutrients  not  absorbed  in  some  Typical  Foods 

To  fact       10 
III.  Amount  of  Energy  and  Building  Material  got  for  One  Shilling 

IN  some  Typical  Foods  -  .  -  •  To  fact      i6 


1.  Calorie  Value  of  Different  Foods    -  -  i  •  • 

2.  To  Illustrate  Influence  of  Shape  on  Surface       -  -  - 

3.  Amount  of  each  Nutritive  Constituent  required  at  different 

Ages         -  -  -  -  . 

4.  Structure  of  Meat  -  .  - 

5.  Composition  of  Meats     ... 

6.  Composition  of  Raw  and  Boiled  Beef 

7.  Composition  of  Fish,  etc. 

8.  Constituents  of  a  Tumblerful  of  Milk 

9.  Percentage  Composition  of  White  and  Yolk  of  Egg 

10.  Actual  Composition  of  an  Egg  .  -  .  .  . 

n.  Relative  Bulks  of  Different  Diets  -  -  .  -  . 

12.  Bulk    and    Weight    of    Different     Foods    yielding     the     same 

Amount  of  Protein       ....... 

13.  Carbon  Food  Cycle         ....... 

14.  Nitrogen  Food  Cycle      ..,.-.. 

15.  Longitudinal  Section  through  a  Grain  of  Wheat  (Low  Power 

\'IE\V)  --....... 

16.  Section  through  Wheat  Grain  (High  Power  View) 


5 
44 

47 
59 
63 
65 

89 
127 

153 

1G7 

177 
182 
182 

190 
191 


XX 


ILLUSTRATIONS 


17.  Composition  of  a  Loaf    - 

18.  Cross  Section  of  a  Potato 

19.  Composition  of  a  Potato 

20.  ,,  M     Turnip 
Carrot 


22. 

23- 
24. 

25- 
26. 
27. 


Cabbage  -..-.. 

Cucumber        .-...- 
Strawberry   ------ 

Apple  ------- 

Banana  .--.-- 

Walnut  -  -         ^  -  .  - 

28.  Shoot  of  Tea  Plant        ------- 

29.  Cells  of  Raw  Potato     ----.-. 

30.  Cells  of  a  Partially  Cooked  Potato  -  -  .  - 

31.  Cells  of  a  thoroughly  Boiled  Potato         -  .  -  . 

32.  The  Aladdin  Oven  --.---- 

33.  Comparison   of  Nutritive  Constituents  required   by  an  Adult 

AND  an  Infant  -.------ 


PA6B 

201 
238 
240 

243 
249 
250 

*52 

260 

3M 
402 
403 
403 
410 

447 


TABLE. 

Table  showing  the  Composition  of  Infant  Foods 


To  fiut    468 


FOOD  AND  DIETETICS 


FOOD    AND    DIETETICS 


CHAPTER  I 


THE  NATURE,  NUTRITIVE   CONSTITUENTS,  AND  RELATIVE 
VALUES  OF  FOODS 

A  food  may  be  defined  as  anything  which,  when  taken  into  the  body,  is 
capable  either  of  repairing  its  ivaste  or  of  furnishing  it  with  material  from 
which  to  produce  heat  or  nervous  and  muscular  work. 

I  am  aware  that  this  definition  is  open  to  criticism,  as  most 
definitions  of  the  term  have  been  before  it,  and  that  it  is  difficult 
to  refuse  to  oxygen  especially  the  right  to  be  regarded  as  a  food 
under  the  terms  of  such  a  description.  But  for  practical  purposes 
the  definition  may  be  allowed  to  stand,  and  it  has  the  advantage  of 
bringing  into  prominence  the  two  main  functions  of  food — in  the  first 
place,  as  a  provision  for  the  growth  and  repair  of  the  fabric  of  the 
body,  and,  secondly,  as  a  source  of  potential  energy  which  can  be 
converted  into  heat  and  work.  In  virtue  of  the  former  function, 
food  provides  for  the  conservation  of  the  material  of  the  body ;  the 
conservation  of  bodily  energy  is  maintained  by  the  latter. 

Substances  which  are  unable  to  help  in  either  of  these  directions 
may  have  a  useful  place  in  the  dietary,  but  they  cannot  be  truly 
regarded  as  foods.  Examples  of  such  substances  are  to  be  found, 
as  we  shall  learn  later,  in  tea,  coffee,  and  the  extractives  of 
meat. 

Most  ordinary  articles  of  diet  are  not  simple  bodies  ;  they  are  made 
up  of  mixtures  of  various  chemical  substances,  some  of  which  are  of 
nutritive  value,  while  others  are  not.    The  former  may  be  spoken  of  as 

z 


2  FOOD  AND  DIETETICS 

the  iintriii>e  coastitueuts  or  '  nutrients,' and  may  be  classified  as 
fellows : 

Organic — 

1.  Nitrogenous: 

Proteins,  e.g.,  casein,  myosin,  gluten,  legumin. 
Albuminoids,  e.g.,  gelatin. 

2.  N  on -nitrogenous  : 

Carbohydrates,  e.g.,  sugar,  starch. 
Fats,  e.g.,  olive-oil,  butter. 
Inorganic — 

Mineral  matters,  ^.g'.,  sodium,  potassium,  lime,  phosphorus, 

chlorine. 
Water. 

Any  article  of  diet,  even  the  most  elaborate  product  of  the  cook's 
art,  can  be  shown,  by  chemical  analysis,  to  contain  one  or  more  of 
the  members  of  these  different  groups  ;  otherwise  it  is  not  a  '  food  * 
at  all. 

The  functions  of  food  are  fulfilled  by  the  different  groups  in 
different  measure.  The  first  function,  that  of  building  up  and 
repairing  the  tissues,  can  be  fulfilled  by  the  proteins  and  by  the 
inorganic  constituents,  and  by  these  alone.  For  this  purpose 
protein,  mineral  matters,  and  water  are  all  necessary.  None  of 
the  three  is  sufficient  by  itself.  The  second  function,  that  of 
serving  as  a  source  of  potential  energy,  is  the  property  of  all  the 
organic  constituents,  although  there  is  a  limited  sense  in  which 
water,  and  even,  perhaps,  the  mineral  constituents,  may  be  regarded 
as  sources  of  energy  too  (see  p.  288). 

The  comparison  of  the  body  to  a  steam-engine  is  a  rather  thread- 
bare and  not  altogether  accurate  analogy,  but  it  is,  perhaps,  the  best 
that  can  be  found.  The  building  material  of  food  corresponds  to  the 
metal  of  which  the  engine  is  constructed,  the  energy-producers  to 
the  fuel  which  is  used  to  heat  the  boiler.  Where  the  body  differs 
from  the  engine  is  that  it  is  able  to  use  part  of  the  material  of  its 
construction  (protein)  for  fuel  also. 

In  regard  to  the  relative  values  of  the  organic  constituents  as 
energy-producers,  physiological  opinion  has  undergone  considerable 
changes  in  the  last  fifty  years.  It  used  to  be  supposed,  mainly  as 
the  result  of  the  powerful  advocacy  of  Liebig,  that  the  proteins  were 
the  chief  producers  of  muscular  energy,  while  the  carbohydrates  and 
fats  merely  acted  as  fuel  and  maintained  the  body  temperature.  We 
now  know  that  this  was  a  mistaken  view.  It  would  seem,  indeed, 
to  be  to  a  large  extent  a  matter  of  indifference  to  the  cells  of  the  body 
whether  they  draw  their  supplies  of  energy  from  protein,  albuminoids, 


FUNCTIONS  OF  NUTRITIVE  CONSTITUENTS         3 

carbohydrate,  or  fat,  although  probably  they  can  get  it  more  rapidly 
and  easily  from  the  three  former  than  from  the  latter.  We  now 
know  also  that  bodily  heat  is  not  a  thing  apart  and  requiring  to  be 
provided  for  by  itself,  but  that  it  is  an  inevitable  accompaniment  of 
cell  life.  Life  and  heat  are  inseparable,  and  in  fulfilling  its  other 
functions  in  the  body  a  cell  cannot  help  producing  heat  also.  Heat, 
in  fact,  is  a  by-product  of  functional  activity  (see  also  p.  48).  Hence 
it  is  a  matter  of  indifference  as  far  as  the  cells  of  the  body  are  con- 
cerned— not  necessarily,  be  it  remembered,  as  far  as  concerns  the 
digestive  organs — whether  we  feed  a  man  on  white  of  egg,  gelatin, 
butter,  or  sugar,  always  supposing  that  these  are  supplied  in  the 
proportion  of  their  dynamic  equivalents. 

As  regards  the  manufacture  and  repair  of  tissue,  however,  no  such 
indifference  prevails.  That  can  be  done  by  protein,  mineral  matters, 
and  water,  and  by  these  alone.  Even  the  albuminoids,  near  though 
they  stand  to  the  proteins,  and  large  though  the  proportion  is  in 
which  they  enter  into  the  bodily  framework,  can  take  no  share  in 
tissue  formation.  This  is  true,  curiously  enough,  even  of  the 
connective  tissues,  from  which  gelatin  is  itself  derived. 

One  may  therefore  classify  the  nutritive  constituents  of  food,  in 
accordance  with  their  functions  in  the  body,  as  follows  : 


Tissue-formers. 
Proteins. 
Mineral  matters. 
Water. 


IVork  and  Heat  Producers. 
Proteins. 
Albuminoids. 
Carbohydrates. 
Fats. 

?  Mineral  matters. 
?  Water. 


It  will  be  observed  that  proteins  alone  are  able  to  fulfil  both  of 
the  functions  of  a  food.  It  is  this  physiological  omnipotence  which 
■^\ves  to  proteins  their  vast  importance  in  the  diet,  and  justifies  the 
proud  title  of  *  pre-eminent '  which  the  name  implies.  Without 
protein  life  is  impossible,  for  the  daily  wear  and  tear  of  tissue  must 
somehow  be  made  good.  With  protein,  plus  water  and  some  mineral 
salts,  life  can  be  healthily  maintained  for  a  practically  indefinite  time, 
as  is  proved  by  the  experience  of  tribes  such  as  the  Indians  of  the 
Pampas,  who  live  year  in  year  out  on  nothing  but  lean  beef  and 
water. 

Such  being  the  uses  of  foods  in  the  body,  the  question  arises. 
How  is  one  to  judge  of  their  relative  value  ?  By  what  criteria  is 
one  to  decide  whether  any  particular  article  of  diet  is  a  good  food  or 
not  ?  The  reply  is  that  such  a  question  can  only  be  decided  by  sub- 
mitting the  food  under  consideration  to  these  four  tests  ; 


4  FOOD  AND  DIETETICS 

1.  Chemical. — What  percentage  of  each  nutritive  constituent  does 
the  food  contain  ? 

2.  Physical. — How  much  potential  energy  is  it  capable  of  yielding  ? 

3.  Physiological. — How  does  it  behave  in  the  stomach  and  intes- 
tine ?     Is  it  easily  digested,  and  to  what  extent  is  it  absorbed  ? 

4.  Economic. — Are  the  nutritive  constituents  which  the  food  con- 
tains obtained  at  a  reasonable  cost  ? 

The  methods  by  which  each  of  these  tests  is  applied  must  now  be 
considered. 

1.  The  Chemical  Test. — Chemical  analysis  can  tell  us  how  much 
of  each  nutritive  constituent  (protein,  carbohydrate,  etc.)  a  hundred 
parts  of  the  food  contain.  By  the  aid  of  this  information  we  can 
form  an  idea  of  the  value  of  the  food  as  a  source  of  building  material 
or  energy.  In  subsequent  chapters  the  percentage  composition  of 
all  the  chief  articles  of  food  will  be  brought  forward  in  detail,  and 
some  types  of  these  will  be  referred  to  immediately. 

2.  The  Physical  Test. — Ever  since  Lavoisier  showed  that  the 
changes  which  food  undergoes  in  the  body  are  essentially  changes 
due  to  oxidation,  the  idea  has  gathered  weight  that  the  amount  of 
heat  which  a  food  is  capable  of  yielding  on  complete  combustion  may 
be  taken  as  a  measure  of  its  value  as  a  source  of  energy,  for  heat  and 
work  are  convertible  terms.  Now,  the  standard  of  heat  production 
is  the  calorie,  which  means  the  amount  of  heat  required  to  raise  the 
temperature  of  i  gramme  of  water  i°  C.  This  is  the  small  calorie. 
For  measuring  the  heat  value  of  foods,  one  employs  for  convenience 
the  large,  or  Kilo-calorie — i.e.,  the  amount  of  heat  required  to  raise 
I  kilo  (or  I  litre)  of  water  i°  C,  or,  which  is  the  same  thing,  i  pound 
of  water  4°  Fahr. ;  and  one  writes  it  Calorie,  with  a  capital  letter. 
All  that  one  has  to  do  in  applying  this  test  is  to  ascertain  of  how 
many  litres  of  water  the  complete  combustion  of  i  gramme  of  the 
food  under  consideration  is  able  to  raise  the  temperature  by  i°  C. 
The  result  gives  the  value  of  i  gramme  of  the  food  in  terms  of 
Calories.  A  large  number  of  very  careful  experiments  of  this  sort 
have  been  made  in  recent  years  with  the  aid  of  the  bomb-calorimeter, 
the  results  of  which  are  graphically  represented  in  the  following 
diagram  (Fig.  i). 

The  suspicion  naturally  arises  that,  although  these  results  hold 
good  for  combustion  outside  the  body,  they  may  not  be  equally  true 
for  combustion  in  the  tissues.  This  suspicion  is  strengthened  when 
one  remembers  that  many  of  the  waste  products  of  metaboUsm, 
such  as  urea,  are  by  no  means  completely  oxidized.  The  body  does 
not  reduce  all  its  fuel  to  the  condition  of  ashes;  some  of  it  is  only 
charred.      Careful  observations   by  Rubner,  however,  have  shown 


CALORIE   VALUE  OF  FOODS 


that,  if  allowance  is  made  for  these  incompletely  oxidized  products, 
combustion  inside  the  body  is  precisely  the  same,  as  far  as  the 
amount  of  energy  liberated  is  concerned,  as  combustion  in  an 
ordinary  furnace,  and  that  the  heat  value  of  i  gramme^  of  each  of 


8  86 


8-60 


4  95 


412 


4- 03 


3-71 


3  51 


3-31 


3  27       I 


303 


2  78 


2-74 


2-4 
I  59  J 


? 


098 

0-98 


Q^ 


BACON. 

BUTTER. 

FAT  GOOSE. 

FAT  PORK. 

fAT  MUTTON. 

MAIZE. 

RICE. 

PEAS. 

FAT   BEEF. 

OOARSE  WHITE  BREAD. 

WHOLE  MEAL  BREAD. 

FINE  WHITE  BREAD. 

CHEESE. 

EOGS. 

LEAN  BEEF 

POTATOES. 

VEAL. 

MILK 

CARROTS.  p5^ 

APPLES.  I&54 

SPINACH. 

ORANGES 

STRAWBERRIES. 

LETTUCE. 

Fig.  I.— Number  of  Calories  yielded  by  the  completb  Combustion 
OF  ONE  Gramme  of  Various  Foods. 

the  three  chief  nutritive  constituents  of  food  when  taken  into  the 
tissues  is  as  follows  :  ^ 

Protein         ..         , 41  Calories. 

Carbohydrates       ..         ..         ,.         ,.         ,.41       „ 
Fat 93      „ 

>  A  gramme  =  i5i  grains.     A  shilling  weighs  about  5^  grammes. 

2  These  figures  represent  the  average  Calorie  value  of  the  nutritive  constituents 
as  contained  in  an  ordinary  mi.xed  diet,  and  after  allowance  has  been  made  for 
defective  absorption  and  for  the  excretion  of  imperfectly  oxidized  residues  by  the 
kidney.  They  may  therefore  be  taken  as  indicating  the  true  worth  to  the  body 
of  the  different  nutritive  constituents  as  sources  of  potential  energy. 


a7o 


6  FOOD  AND  DIETETICS 

The  white  of  one  egg  contains  4  grammes  of  protein,  a  small  lump 
of  sugar  contains  the  same  weight  of  carbohydrate,  and  a  thimbleful 
of  olive-oil  a  similar  amount  of  fat,  so  that  the  latter  will  yield  twice 
as  much  energy  in  the  body  as  the  white  of  a  whole  egg  or  a  small 
lump  of  sugar. 

In  the  Calorie,  then,  we  have  a  standard  w^hich  is  as  applicable  in 
estimating  the  energy  value  of  foods  as  the  foot-rule  is  in  measuring 
length  or  the  ounce  in  calculating  weight.  But  great  as  the  value 
of  this  standard  is — and,  indeed,  it  is  the  only  absolute  standard  by 
means  of  which  all  foods  may  be  compared — one  must  not  over 
estimate  it.  Just  as  in  a  furnace  some  substances,  such  as  anthracite, 
are  '  slow,'  and  others,  such  as  petroleum,  are  '  quick '  fuels,  so  in 
the  human  body  some  of  the  nutritive  constituents  seem  to  yield 
their  energy  to  the  cells  more  rapidly  than  others.  Thus,  proteins, 
carbohydrates,  and  albuminoids  seem  to  be  oxidized  quickly  in  the 
tissues,  fats  more  slowly.  And  this  is  not  a  matter  of  indifference, 
for  if  a  rapid  output  of  energy  is  required,  the  first  group  will  be 
more  serviceable,  whereas  a  slow  production  over  a  long  time  will 
be  equally  well  met  by  fat  (see  also  p.  39).  Further  than  this,  the 
situation  in  which  the  energy  is  liberated  must  also  be  taken  into 
account.  It  may  be  a  matter  of  indifference,  as  far  as  the  heat 
produced  is  concerned,  whether  oxidation  takes  place  in  the  liver  or 
in  the  muscles ;  but  as  regards  the  bodily  function,  of  which,  as  we 
have  seen,  the  production  of  heat  is  but  an  accompaniment,  there  is 
all  the  difference  in  the  world.  The  time  and  the  place,  in  short, 
have  to  be  considered,  as  well  as  the  actual  amount  of  the  energy 
liberated.  The  physical  test  of  a  food  enables  us  to  judge  of  the 
latter  ;  it  tells  us  nothing  of  the  two  former. 

The  method  of  applying  tlie  Calorie  standard  to  a  food  is  very 
simple.  One  has  merely  to  multiply  the  percentage  of  protein  or 
carbohydrate  which  it  contains  by  4*1,  and  the  percentage  of  fat  by 
9-3,  to  get  the  total  Calories  yielded  by  100  parts  of  the  food  in 
question.  Suppose,  for  example,  that  a  specimen  of  milk  contains  in 
every  100  grammes  2  per  cent,  of  protein,  4  per  cent,  of  fat,  and 
6  per  cent,  of  carbohydrate,  then  the  Calories  yielded  by  that 
quantity  of  milk  would  be  as  follows : 

Protein         ••     2x41=  82 

Fat 4x93  =  372 

Carbohydrate         6x41  =  24-6 

Total  Calorie  value  of  100  grammes  of  the  milk       . .     700 
In  Plate  I.  there  is  represented  the  number  of  Calories  contained 
in  I  pound  of  some   typical  foods,  and  the  proportions  of  these 


Plate  T 

FUEL  VALUE  OF 
ONE  POUND  OF    SOME 
TYPICAL   FOODS  . 


The  diagram  represents  the  relative  number 
of  Calories  obtained  from  each  food  in  the  form- 
of  proteidi  e:reen  fat  (yellow),  and  carbohydrate 
(blue)  respectively.  The  following  are  the 
exact  figures  from  which  it  has  been  con- 
structed : 


Food. 

Calories. 

as    « 
Proteid. 

Calories 

as 

Fat. 

Calories 
as  Carbo- 
hydrafe. 

Total  Fuel 

Value 
per  Pound. 

Butter  . . 

l8 

3,559 

none 

3.577 

Peas 

4188 

717 

9825 

1.473 

Cheese  . ., 

553 

750 

none 

1.303 

Bread    .. 

130 

21-5 

976-5 

1. 128 

Eggs      . . 

232 

507 

none 

739 

Beef      . . 

391 

232 

none 

623 

Potatoes 

i8-5 

93 

341-2 

369 

Milk      . . 

67 

168 

87 

322 

Fish  (cod) 

299 

16 

none 

315 

Apples  . . 

9 

none 

229 

238 

The  number  of  Calories  yielded  by  each  in- 
gredient has  been  calculated  from  the  average 
percentage  composition  of  the  different  foods 
as  given  in  subsequent  pages.  It  is  assumed 
that  the  whole  of  each  article  is  edible,  and  no 
allowance  is  made  for  defective  absorption. 


»srr 
5500 

5400 

3300 

5200 

3100 

3000 

2900 

2600 

2700 

2600 

2600 

2400 

2300 

2200 

2100 

2000 

1900 

1800 

1700 

1600 

1500 

1400 

1500 

1200 

1100 

,1000 

900 

800 

700 

600 

600 

400 

300 

200 

100 


■^- zr^ U — Li= 


UJ 

CO 
UJ 
LU 

o 


< 

Ui 

a: 

OQ 


UJ 

0 

(O 

(0 

0 

u. 

UJ 
UJ 

0 
1- 

.2 

-I 

I 

(0 

UJ 

_l 

OL 
0. 

UJ 

CQ 

i 

u. 

< 

DIGESTIBILITY  AND  ABSORBABILITY  7 

which  are  yielded  by  protein,  fat  and  carbohydrate  respectively.  It 
will  be  noticed  that  butter  heads  the  list  as  far  as  the  total  number 
of  Calories  yielded  is  concerned.  This  is  due  to  the  large  amount  of 
fat  which  it  contains.  In  potatoes,  on  the  other  hand,  the  Calories 
yielded  are  mainly  derived  from  carbohydrates,  while  in  cheese  and 
beef  the  total  yield  is  produced  by  protein  and  fat  in  nearly  equal 
proportion.  In  other  words,  as  a  producer  of  energy,  a  pound  of 
butter  is  worth  about  three  times  as  much  as  a  pound  of  cheese, 
and  more  than  five  times  as  much  as  a  pound  of  beef;  but  as  a 
source  of  building  material  both  cheese  and  beef  are  vastly  superior 
to  it.  The  following  table  represents  the  approximate  energy- value 
of  one  ounce  of  some  standard  articles  of  food.  It  may  prove  of 
assistance  in  appraising  the  value  of  any  diet  as  a  source  of  energy  : 


TABLE  OF  ENERGY  VALUES  OF  SOME  FOODS. 


Energy 

Energy 

Energy 

Food. 

Value  per 

Food. 

Value  per 

Food. 

Value  per 

Ounce  (in 

Ounce  (in 

Ounce  (in 

Calories) 

Calories). 

Calories). 

Beef,  lean,  cookec 

60 

Butter 

.    222 

Potato,  boiled 

•      25 

.,     fat 

93 

Plasmon    . . 

.       86 

Carrots,  cooked   . 

.    no 

Lamb,  cooked 

.    62 

Cabbage,  raw 

.       8 

Veal         „ 

.     66 

Cheese,  American     118 

Spinach      ,, 

10 

Pork 

.     88 

,,        Cheddar 

134 

Fowl 

.     80 

,,       Cheshire 

113 

Figs,  dried 

.     92 

Duck 

•     47 

Dutch 

.       90 

,,    stewed 

•     50 

,,        Stilton 

.     124 

Prunes 

.     87 

Tongue,  tinned    . 

.     84 

,,        Camembert  g'i 

Raisins 

.   106 

Sweetbread,  raw. 

50 

,,        Cream 

.     170 

Apples,  raw 

•      14 

Liver,  raw 

.     38 

Grapes 

.     20 

Kidney,  raw 

•     32 

Egg         . .  (in  one)     70 

Bananas    . . 

.     28 

Calf's-foot  jelly    . 

•     25 

Flour,  white 

. . . 100 

Almonds   . . 

.   174 

Cod ,  raw  . . 

.     20 

Bread,      ,, 

•       70 

Walnuts    . . 

.   182 

Salmon,  raw 

.     60 

wholemeal 

62 

Hazel-nuts 

.   190 

Halibut     „ 

■     35 

Biscuits     . . 

.     112 

Eel 

36 

Rusks 

.       98 

Sugar 

•   "5 

Herring    ,, 

■     41 

Marmalade  or  jan 

n     98 

,,         smoked  . 

■     85 

Oatmeal    . . 

.     130 

Haddock,  raw 

.     20 

Rice 

.       98 

Beer,  bottled 

.     17 

smoked 

27 

Stout 

.     20 

Mackerel,  raw     . 

40 

Sago 

.       96 

Lager  beer           . 

.     14 

Turbot 

•     55 

Tapioca     . . 

.       96 

Hock 

.     18 

Sardines  in  oil     . 

80 

Arrowroot . . 

.       96 

Claret 

.     18 

Oysters 

•     15 

Macaroni  . . 

.     100 

Port 
Sherry 

.     41 
•     38 

Milk 

.     20 

Peas  (dried),  raw 

.       92 

Spirits 

.     83 

Cream  (^5  %) 

126 

„      (green),  „ 

.       22 

Owing  to  the  great  variations  in  the  composition  of  foods  the  energy  values 
given  in  this  table  are  merely  approximative ;  in  the  case  of  some  foods,  such, 
for  example,  as  bacon  and  ham — the  variations  are  so  great  as  to  render  any  state- 
ment as  to  the  average  value  useless.     In  every  case  the  value  of  the  edible 


8  FOOD  AND  DIETETICS 

portion  of  the  food  is  alone  represented.  So  far  as  possible,  the  energy  value  has 
been  calculated  for  the  food  as  prepared  for  the  table,  but  in  many  instances, 
owing  to  the  elaborate  methods  of  cooking  employed,  this  has  been  found  im- 
practicable, and  the  value  of  the  raw  food  is  given  instead.  (For  further  infor- 
mation on  this  point  see  a  paper  by  Schwenkenbecher,  '  Die  Nahrwerthberech- 
nung  tischfertiger  Speisen,'  in  the  Zeitsck.  f.  Physik.  und  Didt.  Therapie,  iv.,  igoi, 
p.  380.) 

3.  The  Physiological  Test. — It  is  not  enough  that  a  food  should 
contain  a  considerable  proportion  of  protein,  carbohydrate  and  fat, 
and  should  be  capable  of  yielding  energy  on  oxidation.  It  must 
also  be  of  such  a  nature  that  it  can  be  easily  digested  in  the  stomach, 
and  more  or  less  completely  absorbed  into  the  blood.  Such  sub- 
stances as  sawdust,  petroleum,  and  hoof- parings  might  pass  the 
chemical  and  physical  tests  easily  enough,  but  they  are  of  no  use 
in  the  body,  for  they  cannot  be  digested  and  absorbed.  For  this 
reason  the  behaviour  of  a  food  in  the  stomach  and  intestine  must 
be  reckoned  with  before  any  opinion  can  be  pronounced  as  to  its 
value  in  the  diet. 

In  studying  this  subject,  one  must  distinguish  very  clearly  between 
the  meaning  of  the  term  '  digestibility  '  in  its  popular  sense  and  that 
attached  to  it  by  physiologists.  When  one  speaks  of  a  food  as  being 
'  indigestible,'  one  ordinarily  means  that  it  is  a  food  which  is  apt  to 
produce  feehngs  of  pain  and  discomfort  in  the  stomach.  When  a 
physiologist  uses  the  term,  he  usually  means  that  the  food  to  which 
it  is  applied  is  one  which  is  only  imperfectly  absorbed  into  the 
blood.  Cheese  is  an  indigestible  food  in  the  former,  and  green 
vegetables  in  the  latter,  sense.  To  avoid  confusion,  it  is  better  to 
adhere  to  the  popular  usage  of  the  expression  '  digestibility,'  and,  if 
one  may  use  a  rather  ugly  word,  to  employ  the  term  '  absorbability  ' 
to  indicate  the  completeness  with  which  the  constituents  of  a  food 
can  pass  from  the  intestine  into  the  circulation.^ 

By  a  digestible  food,  then,  I  mean  one  which  is  disposed  of  by  the 
stomach  with  little  trouble,  and  without  producing  any  feelings  of 
discomfort  or  pain.  The  only  absolute  criterion  of  the  digestibility 
of  a  food  in  that  sense  is  the  length  of  time  which  it  has  to  remain 
in  the  stomach  before  it  is  fit  to  be  passed  on  into  the  intestine. 
The  shorter  the  time  a  food  needs  to  stay  in  the  stomach,  the  greater 
is  its  digestibility  ;  and  the  longer  the  period  which  must  elapse 
before  it  can  pass  on  into  the  intestine,  the  more  indigestible  it  is. 

In  a  subsequent  chapter  we  shall  have  occasion  to  study  the 
results  of  a  large  number  of  exact  experiments  which  have  been 

'  In  this  nomenclature  '  digestibility  '  would  correspond  to  the  German  ertrag- 
barkeit,  and  '  absorbability  '  to  ausnutzlarkeit. 


ABSORPTION  OF  DIFFERENT  FOODS  g 

performed  to  ascertain  the  length  of  time  which  different  foods 
remain  in  the  stomach — experiments,  that  is  to  say,  on  the  com- 
parative digestibility  of  foods.  I  would  only  point  out  heie  some  of 
the  factors  which  are  of  importance  in  determining  the  length  of 
time  required  in  any  particular  case.  It  must  be  borne  in  mind 
that  one  of  the  chief  duties  of  the  stomach  is  to  reduce  the  food  to 
a  fluid  or  semi-fluid  condition.  The  more  difficult  the  process  of 
solution  is,  the  longer  must  the  food  remain  in  the  stomach.  Now, 
bulky  foods,  and  those  of  a  dense  and  firm  consistency,  or  which 
contain  a  large  proportion  of  solid  matter,  will  take  longer  to 
dissolve,  and  will  consequently  remain  longer  in  the  stomach  than 
foods  of  opposite  properties.  Obviously,  then,  foods  of  such  a 
character  may  be  regarded  as  comparatively  indigestible.  In  addi- 
tion to  these  factors,  certain  others  must  be  taken  into  account, 
such  as  the  temperature  of  the  food,  the  proportion  of  fat  which  it 
contains,  and  the  presence  or  absence  of  substances  in  it  which  are 
capable  of  exciting  the  secretion  of  the  digestive  fluids.  All  of  these 
will  be  fully  considered  later  on. 

Before  leaving  the  subject,  mention  must  be  made  of  one  other 
quality  of  foods  which  seems  specially  to  affect  the  stomach,  and 
which,  for  want  of  a  better  term,  is  commonly  called  their  satis- 
fying power.  It  is  a  matter  of  common  knowledge  that  some  foods 
appease  the  appetite  and  allay  the  feelings  of  hunger  longer  than 
others.  Such  foods  are  said  to  be  'satisfying,'  or,  to  use  a  slang 
expression,  '  stodgy.'  What  it  is  which  confers  this  quality  upon 
some  foods  rather  than  others  is  not  perfectly  clear ;  but  there  is 
reason  to  believe  that  it  depends  to  some  extent  upon  the  amount 
of  fat  which  the  food  contains.  Foods  rich  in  fat  are  more  satis- 
fying than  others.  It  is  believed  to  be  for  this  reason  that  eggs 
possess  the  quality  under  consideration  in  no  ordinary  degree. 
Other  properties,  such  as  the  amount  of  soUd  matter  to  be  digested 
and  the  bulk  of  the  food,  no  doubt  also  play  a  part  in  producing  the 
feeling  of  *  satisfaction  ';  but  whatever  the  explanation  of  the  quality 
is,  it  has  certainly  to  be  reckoned  with  in  estimating  the  value  of  a 
food  from  the  stomach  point  of  view. 

Absorbability. 
A  large  number  of  experiments  have  been  performed  in  recent 
years  in  order  to  ascertain  the  degree  to  which  the  different  con- 
stituents of  various  foods  are  absorbed  into  the  blood.    The  average 
results  for  the  chief  groups  of  foods  are  shown  in  the  following  table  :^ 

»  U.S.  Dept.  of  Agriculture,  Office  of  Experiment  Stations,  Circular  no. 


xo 


FOOD  AND  DIETETICS 


COEFFICIENTS  OF  DIGESTIBILITY  AND  AVAILABILITY  OF 
ENERGY  OF  DIFFERENT  GROUPS  OF  FOOD. 


Kind  of  Food. 


Meat  and  fish   . .         . .         . . 

Eggs       

Dairy  products. . 

Total  animal  foods  of  mixed  diet 

Cereals    . . 

Legumes,  dried  . .  . . 

Sugars  and  starches    . .  . . 

Vegetables         . .  . ,  . . 

Fruits 

Total  vegetable  foods  of  mixed  diet 

Total  food 


Protein. 


Per  Cent. 
97 
97 

97 
97 
85 

78 

83 
85 
84 
92 


Fat. 


Per  Cent. 
95 
95 
95 
95 
90 
90 

90 

90 
90 
95 


Carbo- 
hydrates. 


Per  Cent. 

98 
98 
98 
98 

97 

98 

95 
90 

97 
97 


Availability 
of  Energy. 


Per  Cent. 
87 
89 
93 
89 
91 
83 
98 

91 
88 
92 
91 


The  method  of  experiment  consists  in  analysing  the  food  to  be 
investigated,  and  then  ascertaining,  from  an  examination  of  the 
faeces,  the  proportion  of  its  protein,  carbohydrate  and  fat  which 
escapes  absorption. 

In  the  accompanying  diagram  (Plate  II.)  there  is  shown  the  per- 
centage of  each  nutritive  constituent  which  is  unabsorbed  in  some 
typical  foods.    It  will  be  well  to  consider  each  constituent  separately. 

1.  Absorption  of  Proteins. — One  of  the  first  points  which  arrest 
the  attention  on  looking  at  the  diagram  is  that,  of  the  three  chief 
nutritive  constituents,  the  proteins  are  the  least  completely  absorbed. 
Whether  this  is  quite  an  accurate  way  of  stating  the  case,  whether 
one  should  not  rather  say  that  foods  differ  more  in  regard  to  the 
waste  of  nitrogen  which  they  cause  than  in  any  other  respect,  is,  as 
has  been  shown,  a  matter  of  indifference.  The  fact  remains  that 
with  some  foods  much  nitrogen  is  excreted  in  the  faeces,  with  others 
little.  Closer  inspection  will  show  that  in  this  respect  foods  may  be 
divided  into  two  groups.  On  a  purely  animal  diet  (milk,  eggs,  beef) 
there  is  but  little  nitrogen  lost ;  whereas  with  vegetable  foods 
(carrots,  potatoes,  peas,  etc.)  the  waste  of  nitrogen  is  very  consider- 
able, amounting  in  the  case  of  carrots  to  nearly  40  per  cent,  of  the 
total  protein  consumed.  The  reason  for  this  loss  of  protein  on  a 
vegetable  diet  will  be  considered  later  (p.  169),  but  it  must  be 
pointed  out  here  that  the  smaller  the  amount  of  nitrogen  a  food 
contains,  the  greater  is  the  apparent  loss  of  it  in  the  faeces,  for 
the  higher  is  the  ratio  of  the  nitrogen  derived  from  the  digestive 
juices  to  that  in  the  food.  This  explains,  to  some  extent  at  least, 
the  great  apparent  loss  of  protein  in  such  foods  as  carrots  and  rice. 

2.  Absorption  of  Fat. — Compared  with  the  proteins,  fat  is  apparently 
very  completely  absorbed.  This  probably  means  that  the  residue 
of  the  intestinal  juices  contains  almost  no  fat ;  hence  nearly  all  of 
that  which  appears  in  the  faeces  is  derived  from  the  unabsorbed  fat 


F'late   II 


PERCENTAGE  OF  NUTRIENTS   NOT 
ABSORBED    IN   SOME  TYPICAL  FOODS 


00 
95 
90 
85 
80 
7S 
70 
65 

60  r 

56 


60 
45 


<o  to 


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Li-  CO  rf 

UJ  (^  LU 

Llj  o  QC 

OQ  LU  CD 


o 

a: 


ABSORPTION  OF  FATS  AND  CARBOHYDRATES     ii 

of  the  food.  In  the  case  of  most  of  the  vegetable  foods,  the  amount 
of  fat  which  they  contain  is  so  small  that  its  absorption  cannot  be 
accurately  estimated. 

Regarding  the  absorbability  of  fat,  one  generalization  can  be 
made  with  a  fair  amount  of  certainty,  and  it  is  this  :  the  lower  the 
melting-point  of  the  fat,  the  more  completely  is  it  absorbed.  The 
explanation  of  this,  of  course,  is  that  a  fat  which  is  fluid  at  the  body 
temperature  is  more  easily  taken  up  into  the  blood  than  one  which 
remains  more  or  less  solid.    The  following  are  illustrative  examples : 

P  .  Melting-  Percentage 

point.  unabsorbed. 

Butter 37°  C.  2J 

Bacon 48°  C.  •  8 

Mutton-fat 52°  C.  lo 

The  total  amount  of  fat  which  can  be  absorbed  in  one  day  is  a 
matter  of  some  interest.  It  has  been  found  by  experiment  that 
150  grammes  (about  5^  ounces)  can  be  absorbed  without  appreciable 
loss.  Above  this  point  the  waste  increases  considerably,  but  even 
when  twice  that  quantity  is  taken  the  loss  is  less  than  45  per  cent. 
The  practical  deduction  from  these  facts  is  that  one  need  have  no 
hesitation  in  ordering  a  patient,  say  a  diabetic,  to  consume  ^  pound 
of  butter  every  day.  There  is  no  likelihood  of  this  quantity  sur- 
passing the  absorptive  powers  of  the  intestine. 

3.  Absorption  of  Carbohydrates. — As  is  clearly  shown  in  the  diagram, 
the  carbohydrates  are  more  completely  absorbed  than  any  other 
nutritive  constituent  of  the  food.  Sugar  probably  never  fails  to 
enter  the  blood  to  the  last  grain,  and  even  starch  only  reappears  in 
the  faeces  when  taken  in  a  form  specially  difficult  of  absorption,  such 
as  in  green  vegetables  or  in  coarsely  divided  masses.  Hence  it  is 
that  foods  which  consist  mainly  of  carbohydrates,  such  as  rice 
leave,  on  the  whole,  less  solid  residue  in  the  intestine  than  any 
other,  animal  foods  not  excepted.  In  other  words,  the  statement 
sometimes  made,  that  vegetable  are  less  perfectly  absorbed  than 
animal  foods,  is  not  universally  true,  although  it  may  hold  good  in 
the  majority  of  cases. 

Seeing  that  a  given  weight  of  fat  represents  about  two  and  a 
quarter  times  as  much  energy  as  an  equal  weight  of  protein  or 
carbohydrate,  it  is  evident  that  the  loss  to  the  body  of  a  given 
amount  of  fat  through  non-absorption  is  of  more  importance  than 
an  equal  loss  of  any  of  the  other  nutritive  ingredients.  For  this 
reason  it  is  perhaps  more  instructive  to  represent  the  percentage  of 
the  total  Calories  which  a  food  contains  which  are  lost  in  this  way, 
rather  than  to  give,  as  has  been  done  above,  the  actual  loss  of  each 


12  FOOD  AND  DIETETICS 

constituent.     Adopting  this  plan,  it  will  be  found  that  the  loss  in 

some  typical  foods  is  as  follows  : 

p,     ,  Percentage  of  Calories  lost        p     ,  Percentage  of  Calories  losi 

^'°°'^'  through  N on -absorption.  "  through  Non-absorption. 

Rice    ..         ..  2-6  Meat   ,.  ..  5-5 

Milk    ..         ,.  4-4  Potatoes         ..  6'8 

Bread..         ..  4*5  Carrots  ..  20-2 

(Rubner.) 

It  will  be  observed  that  from  this  point  of  view  rice  and  milk  are 
much  more  economical  foods  than  potatoes  and  meat. 

Absorption  of  a  Mixed  Diet. 

Most  of  the  above  experiments  have  necessarily  been  made  when 
the  subject  of  them  was  living  upon  a  single  article  of  diet  only. 
But  in  ordinary  life  most  people  live  upon  a  mixed  diet,  and  it 
becomes  necessary  to  inquire  to  what  extent  absorption  goes  on 
under  these  circumstances,  and  how  the  presence  of  one  food  in 
the  intestine  affects  the  absorbability  of  another.  In  general  terms 
it  may  be  said  that  the  constituents  of  a  mixed  diet  are  better 
absorbed  than  those  of  any  one  article  of  food  when  taken  by  itself. 
This  comes  out  very  clearly  in  some  observations  recorded  in 
America, 

An  average  of  eleven  experiments^  on  ordinary  mixed  diet  gave  the 
following  results : 


Constituents.  Percentage 

absorbed. 

Organic  matter        ..         ..     957 


-,      ...       .  Pir  cent  age 

Constituents.  absorbed. 

Fat 94  4 


Protein  926       I   Carbohydrate  ..         ..     97  "i 

In  another  experiment^  the  diet  consisted  of  beef,  eggs,  bread  and 
butter,  milk,  potatoes  and  fruit.  The  following  were  the  percentages 
absorbed : 

Protein  ..         ..         ..94-9       I    Carbohydrate  ..         ..     98-9 

Fat 96-9       I 

In  a  third  set  of  experiments^  the  subject  lived  upon  beef,  white 
and  brown  bread  and  butter,  milk,  oatmeal,  potatoes  and  fruit,  and 
absorbed  of  their  constituents  the  following  amounts  : 

Protein          ..         ..    91-3  per  cent.    I    Carbohydrate  ..     977  per  cent. 

Fa' 95-9         „  I 

The  absorption  of  protein  is  more  favourably  influenced  by  the 
presence  of   a   mixture  of   foods   than   is  that  of   any  other  con- 

^  Wait,  United  States  Department  of  Agriculture,  Bull.  53. 

^  Ninth  Annual  Report,  Storrs  Agricultural  Experiment  Station,  p.  179. 
Ibid.     A  very  complete  summary  of  all  the  existing  experiments  upon  the 
absorption   of  foods  will  be  found   in  Bull.  45,  United  States  Department  of 
Agriculture,  1898. 


BALLAST  13 

stituent.  This  is  probably  to  be  explained  by  the  fact  that  the 
production  of  organic  acids  from  the  carbohydrates  of  a  mixed  diet 
exerts  a  restraining  influence  upon  the  destruction  of  proteins  in 
the  intestine  by  putrefactive  bacteria.^  Thus,  it  has  been  found  by 
actual  experiments  that  the  constituents  of  bread  and  milk  are  better 
absorbed  when  these  foods  are  taken  together  than  when  either  is 
consumed  alone. '  The  same  was  found  by  Rubner  to  hold  good  for 
a  mixture  of  milk  and  cheese,  as  compared  with  either  of  these 
articles  taken  separately. 

Taking  the  general  results  of  all  experiments,  it  has  been  calculated 
that  the  following  proportions  of  nutritive  constituents  will  be 
absorbed  from  a  mixed  diet'  : 

Protein.  Fat.  Carbohydrates. 

Animal  foods       . .         . .     98  per  cent.  97  per  cent.  100  per  cent 

Cereals  and  sugars         ..     85        ,,  90       ,,  98,, 

Vegetables  and  fruits    ..80       ,,  90       ,,  95       „ 

Ordinary  mixed  diet      . .     92       „  94^     ,,  98^     ,, 

The  following  table*  represents  the  average  *  physiological  value ' 
of  some  diets  after  allowing  for  losses  from  defective  absorption  and 
the  excretion  of  incompletely  oxidized  residues,  such  as  urea : 

Percentage  of  Total  Calories 
Diet.  available  for  Purposes 

of  Nutrition. 
Human  milk         ..  .,         ..  ..  ..  ..     gi'6 

Cow's  milk  ("infant)         ..  ..  ..  ..  ..     90-7 

,,     (adult)  89-8 

Mixed  diet,  rich  in  fat    . .  . .  . .  . .  . .     904 

,,         ,,      poor  in  fat  ..  ..  ..  ..  ..     89 '3 

Bread         82-1 

Potatoes ..         ..92*3 

Meat         76-8 

It  may  be  asked  whether  it  is  to  be  regarded  as  an  advantage  in 

a  food  that  it  is  completely  absorbed.     The  reply  would  be  that  a 

food  which   leaves  a  moderate   amount  of  unabsorbed   residue   is 

certainly   preferable.      The    intestine   seems   to   require   a   certain 

amount  of  ballast — probably  to  act  as  a  stimulus  to  its  peristalsis. 

If  herbivorous  animals,  such  as  rabbits,  are  fed  upon  a  diet  which 

leaves  little  or  no  residue,  it  has  been  found  that  they  suffer  from 

aflfections  of  the  intestine  which  may  even  prove  fatal,  whereas  such 

eflfects  can  be  avoided  by  adding  to  the  food  any  material  which 

leaves  behind  an  unabsorbed  residue.     Even  in  the  case  of  man, 

who  has  a  considerably  shorter  intestine,  it  is  observed  that  a  diet 

1  The  fatty  acids  liberated  from  neutral  fats  may  perhaps  act  in  a  similar  way. 
'  Bull.  53,  United  States  Department  of  Agriculture,  p.  44,  1898. 
'  Atwater,  Storrs  Agricultural  Experiment  Station,  Ninth  Annual  Report,  p.  1S7, 
1896,  and  Bull.  117  Off.  of  Experiment  Stations,  U.S.Dept.  of  Agriculture,  1902. 
*  Rubner,  Zeiisch.f.  Biologie,  1901,  xlii.,  p.  261. 


j^  FOOD  AND  DIETETICS 

which  is  practically  completely  taken  up  into  the  blood,  such  as  one 
composed  exclusively  of  meat,  is  prone  to  be  accompanied  by 
intestinal  disturbances.  On  the  other  hand,  a  diet  which  leaves 
behind  a  very  large  residue  is  not  only  wasteful  in  an  economic 
sense,  but  demands  for  its  manipulation  and  evacuation  an  undue 
amount  of  muscular  and  nervous  energy  on  the  part  of  the  intestine. 
This,  as  we  shall  see  later,  is  one  of  the  drawbacks  to  a  purely 
vegetable  diet.  In  conditions  of  disease  it  may  be  necessary 
to  take  advantage  of  the  behaviour  of  different  foods  in  respect  of 
absorption.  If  peristalsis  is  exaggerated,  as  in  diarrhcea,  one  does 
well  to  select  those  foods  which  are  most  completely  absorbed,  e.g., 
rice,  minced  meat,  or  milk.  In  the  opposite  condition  of  diminished 
peristalsis  and  constipation,  it  is  important  to  supply  the  intestine 
with  a  larger  amount  of  '  ballast '  than  usual,  and  such  foods  as 
green  vegetables  and  whole-meal  bread  most  perfectly  fulfil  the 
requirements  of  the  case. 

Before  leaving  this  subject  two  questions  present  themselves  for 
consideration.  The  first  is,  may  there  not  be  individual  differences 
in  absorptive  capacity  ?  In  other  words,  may  some  persons  not 
extract  the  nutritive  constituents  from  their  food  more  thoroughly 
than  others  ?  It  might  be  supposed  that  in  this  way  some 
anomalies  in  dietetics  would  find  an  easy  explanation,  such,  for 
example,  as  the  unequal  amounts  of  fat  and  flesh  laid  on  by  different 
individuals  on  the  same  diet.  Tempting  though  this  explanation  is, 
it  must  be  admitted  that  there  are  no  exact  observations  in  favour 
of  it,  but  rather  the  reverse.  It  has  been  found,  for  example,  that 
persons  who  have  been  accustomed  to  a  purely  vegetable  diet  for 
years  absorb  its  constituents  no  better  than  those  to  whom  such  a 
regimen  is  a  comparative  novelty  (see  p.  179).  The  large  number 
of  observations  which  have  been  made  on  different  individuals  with 
the  common  articles  of  food  have  also  failed  to  elicit  any  striking 
disparity  in  the  degree  to  which  absorption  takes  place,  and  even 
where  the  intestines  are  considerably  deranged  by  disease  there  is  a 
remarkable  tendency  for  the  ordinary  degree  of  absorptive  capacity 
to  be  maintained. 

The  second  question  which  arises  is  this.  Granted  that  the  con- 
stituents of  two  foods  are  absorbed  with  equal  completeness,  may 
it  not  be  true  that  the  process  of  absorption  demands  a  greater 
expenditure  of  energy  in  the  one  case  than  the  other  ?  Undoubtedly 
it  is  so  ;  or,  rather,  the  amount  of  energy  which  requires  to  be 
expended  in  order  to  reduce  a  food  to  a  state  in  which  absorption 
is  possible  may  be  greater  in  one  case  than  in  another.  It  has  been 
found,  for  example,  that  for  the  same  amount  of  protein  actually 


BALLAST  15 

absorbed  three  to  four  times  as  much  energy  has  to  be  expended  in 
the  case  of  bread  as  in  that  of  milk.  This  is  one  of  the  advantages 
of  a  milk  diet.  Its  absorption  demands  but  little  intestinal  labour. 
That  such  labour  is  by  no  means  inconsiderable  is  shown  by  the 
fact  that,  of  the  total  amount  of  energy  supplied  to  the  body  by  a 
diet  of  bread  and  butter,  fully  5  per  cent,  is  expended  merely  in  its 
digestion  and  absorption.^ 

It  seems  likely  that  in  future  more  attention  than  hitherto  will 
require  to  be  paid  to  this  aspect  of  digestion. 

Reviewing  the  results  yielded  by  the  appUcation  of  the  physiological 
test  to  foods,  it  must  be  admitted  that  they  are  of  great  value.  Had 
it  always  been  carefully  applied,  certain  common  dietetic  fallacies 
would  never  have  gained  the  wide  prevalence  they  at  present  enjoy. 
Examples  of  these  are  the  supposed  superiority  of  whole-meal  to 
white  bread  (p.  216),  and  the  erroneous  notion  that  the  fungi  might, 
if  properly  taken  advantage  of,  prove  a  cheap  and  valuable  source  of 
food.  A  more  egregious  instance  is  to  be  found  in  the  idea  that 
petroleum  can  act  as  a  substitute  for  cod-liver  oil.  I  have  elsewhere^ 
advanced  experimental  evidence  to  prove  that  petroleum  cannot  be 
absorbed  by  the  human  intestine.  It  is  thus  ruled  entirely  out  of 
the  class  of  true  foods  by  the  application  of  the  physiological  test, 
even  if  it  were,  as  it  is  not,  admissible  to  that  class  in  virtue  of  its 
chemical  properties. 

Maly  has  aptly  compared  foods  to  ore,  and  their  nutritive  con- 
stituents to  the  metal  which  the  ore  contains.  Just  as  the  metal  has 
to  be  extracted  from  the  ore  before  it  is  of  any  use,  so,  by  the  pro- 
cess of  digestion,  the  nutritive  constituents  have  to  be  extracted 
from  a  food  before  they  can  be  absorbed.  The  chemical  test  tells 
us  how  much  metal  is  present  in  the  ore ;  the  physiological  test  tells 
us  whether  or  not  the  body  is  capable  of  extracting  it. 

4.  The  Economic  Test. — Having  ascertained  the  richness  of  a  food 
in  nutritive  constituents,  the  amount  of  energy  which  it  is  capable 
of  yielding,  and  the  readiness  with  which  it  can  be  digested  and 
absorbed,  we  have  still  to  inquiire  whether  the  nutriment  which  it 
affords  is  obtained  at  a  reasonable  cost.  For  this  we  require  an 
economic  test.  The  simplest  way  of  applying  such  a  test  is  to  find 
out  how  much  energy  (in  Calories)  and  how  much  building  material 
(in  protein)  one  can  get  for  a  particular  sum  when  invested  in  the 
food  under  consideration.  In  the  following  diagram  (Plate  III.) 
the  results  of  the  application  of  this  test  to  various  typical  articles  of 
diet  are  set  out.     Looking  first  at  the  energy  (Calories)  obtained,  one 

1  Pawlow,  'Die  Arbeit  der  Verdauungsdrusen,'  p.  8g. 
*  British  Medical  Journal,  1899,  i.  724. 


i6  FOOD  AND  DIETETICS 

sees  that  bread  leads  the  way,  a  shilling  invested  in  bread  yielding 
10,764  Calories,  or  more  than  three  times  as  much  as  is  obtained  for 
the  same  sum  in  milk,  and  more  than  ten  times  as  much  as  can  be 
got  in  the  form  of  beef. 

In  the  matter  of  building  material,  on  the  other  hand,  peas  come  first, 
a  shilling's  worth  containing  572  grammes  of  protein,  or  fully  twice 
as  much  as  can  be  obtained  in  cheese  for  the  same  expenditure.  In 
the  form  of  eggs  or  beef  building  material  is  even  more  costly,  the 
former  being  more  than  eight,  and  the  latter  more  than  five,  times  as 
expensive  a  source  of  protein  as  peas. 

Taking  the  results  as  a  whole,  it  will  be  observed  that  the  vegetable 
foods  are  far  cheaper  than  the  animal  foods,  whether  one  uses  them 
as  sources  of  energy  or  of  building  material.  This  is  one  of  the 
strongest  arguments  in  favour  of  vegetarianism. 

Of  the  various  nutritive  constituents  of  food,  carbohydrate  is  by 
far  the  cheapest.  The  reason  is  that  carbohydrates  make  up  the 
chief  bulk  of  most  vegetable  foods,  and  th>  ■  are,  as  we  have  just 
seen,  considerably  cheaper  than  the  foods  of  animal  origin.  The 
further  question,  why  vegetable  foods  are  cheap,  will  be  considered 
in  another  chapter  (p.  181). 

Compared  with  the  carbohydrates,  protein  and  fat  are  very  ex- 
pensive constituents  of  foods,  fat,  perhaps,  especially  so.  'It  is  a 
remarkable  fact,'  says  Buckle,^  'and  one  to  which  I  would  call 
particular  attention,  that  owing  to  some  more  general  law,  of  which 
we  are  ignorant,  highly  carbonized  food  is  more  costly  than  food  in 
which  comparatively  little  carbon  is  found.'  The  '  more  general  law ' 
of  which  he  speaks  is  really  the  same  law  by  which  animal  foods 
are  dearer  than  vegetable.  By  far  the  larger  part  of  the  fat  in  our 
diet  is  derived  from  animal  sources.  The  dearness  of  fat  is  un- 
fortunate, and  is  not  uncommonly  a  source  of  trouble  in  practical 
dietetics.  One  might  mention,  as  an  instance,  the  difficulty  which  a 
diabetic,  who  has  at  the  same  time  the  misfortune  to  be  a  poor  man, 
finds  in  providing  himself  with  a  diet  suited  to  his  disease.  The 
same  remark  applies,  though  less  forcibly,  to  protein. 

The  practical  importance  of  having  an  economic  test  for  foods  is 
the  more  convincingly  felt  when  one  realizes  that  the  market  pria 
of  a  food  is  no  indication  of  its  real  money  value.  In  the  market 
one  pays  for  flavour  and  rarity,  not  for  nutritive  qualities.  It  is  the 
demands  of  the  palate  which  cost,  not  those  of  the  stomach,  and  we 
pay  for  aesthetic  qualities  in  foods  just  as  in  dress  we  pay  for  '  cut ' 
and  ornament,  not  for  material  to  keep  us  warm.  Suppose,  for 
example,  that  one  wishes  to  buy  a  pound  of  fish.  If  sole  is  the 
*  Buckle,  '  History  of  Civilization,'  vol.  i.,  p.  62. 


Calories 


10.500  W. 


10.000  ^ 


9.500  ^ 


I. 


9.000  ^  ^ 

i 

-  I 

7.000  t^  I^ 


Plate  HI 

AMOUNT  OF  ENERGY- (Calories) 
&  BUILDING   MATERIAL  (Proteid^ 
GOT    FOR  ONE  SHILLING 
IN  SOME  TYPICAL  FOODS 


6.500  ^.    ^ 


1 1 


6.000  ^    '^ 


5.500  I     I 

5.000  I   I 

i  I 

4.500  I     I 

i 


4.000 


3.500  ^    g 


2.500  g 


2.000  P^ 


1.500   ^. 


1.000 


500 


1 


iilli 

I! 

If 


I 


i 


ill 
III 


I 


i| 


-^ 


i2^ 


Grammes 
-600 

-550 

-500 

-450 

-400 

-350 

-300 

-250 

-200 

-150 

100 

50 


RELATIVE  COST  OF  FOODS  17 

form  selected,  it  may  cost  is.  6d. ;  haddock  would  yield  quite  as 
much  nutriment  for  ^d. ;  i.£.,  in  the  former  one  is  paying  ±d.  for 
nutriment,  and  is.  2d.  for  other  qualities.  Or  take  the  case  of 
arrowroot.  A  pound  of  the  best  Bermuda  costs  2s.  gd.,  St.  Vincent 
only  3d.  or  4d.  Yet  both  are,  in  a  chemical  sense,  merely  starch, 
and  physiologically  their  behaviour  is  identical.  It  is  the  same  with 
cheese.  A  pound  of  Stilton  costs  is.  2d.  The  same  amount  of 
nutriment  can  be  had  in  Dutch  or  American  for  6d.  These  examples 
might  be  multiplied  indefinitely,  but  they  are  sufficient  to  show  that 
the  maxim  '  cheap  and  nasty '  does  not  hold  good  for  foods.  I 
should  be  sorry  to  deny  that  aesthetic  considerations  should  not  be 
taken  into  account  in  selecting  a  dietary.  It  may  be  true  that  the 
sense  of  taste  is  as  much  worth  cultivating  as  that  of  sight  or 
hearing,  but  if  one  resolves  to  go  in  for  luxury  it  is  well  to  do  so 
knowingly,  and  not  imagine  that  one  is  nourishing  the  body  while 
merely  pleasing  the  palate. 

To  students  and  practitioners  of  medicine,  a  knowledge  of  the 
economic  value  of  foods  is  of  special  importance.  It  is  frequently 
our  duty  to  see  that  the  diet  of  a  patient  is  enriched  in  special  direc- 
tions, most  commonly,  perhaps,  in  that  of  protein  or  fat.  There  is 
no  use  in  recommending  to  a  poor  man  chicken  and  cream.  He 
cannot  afford  to  buy  them.  It  is  worth  while  to  remember, 
however,  that  the  cheapest  sources  of  building  material  are  skitn 
milk,  some  forms  of  fish  (e.g.,  herring  or  salt  fish),  cheese,  the 
cheaper  cuts  of  meat,  and,  if  his  digestion  be  good,  the  pulses,  while 
the  most  economical  forms  of  fat  are  margarine  and  dripping. 
These  articles  are  within  the  reach  of  almost  everybody. 

To  the  poorer  classes,  too,  such  knowledge  is  of  special  value.  It 
must  be  remembered  that,  of  the  wages  which  a  working  man 
receives,  fully  50  per  cent,  must  be  spent  on  food  alone,  and  that 
the  poorer  a  man  is  the  larger  is  his  proportionate  expenditure  on 
this  item.  And  yet  the  pathetic  thing  is  that  it  is  just  this  class 
of  the  community  whose  food  purchases  are  apt  to  be  the  most 
irrational.     There  is  room  here  for  popular  instruction. ^ 

Of  two  other  points  which  concern  the  economy  of  foods  no  mention 
has  been  made  ;  I  refer  to  '  waste '  and  the  cost  of  cooking.  Of  avoid- 
able waste  there  is  no  need  to  speak,  though  in  this  country  at  least 
we  have  much  to  learn  in  that  respect  from  some  of  our  Continental 
neighbours.     By  unavoidable   waste  one  means  that  a  considerable 

^  See  'Family  Budgets'  (London:  P.  and  S.  King),  1896,  and  Oliver,  'The 
Diet  of  Toil,  and  its  Relation  to  Wages  and  Production,'  a  paper  read  at  the 
Congress  of  Hygiene  and  Demography,  Buda-Pesth,  September,  1894. 

2 


i8  FOOD  AND  DIETETICS 

proportion  of  much  food  as  purchased  is  not  in  an  edible  form  ;  I 
refer  to  such  things  as  the  skin  and  skeleton  of  fish,  the  bone  of 
meat,  and  some  parts  of  green  vegetables.  In  ordinary  cuts  of  meat 
the  unavoidable  waste  may  be  reckoned  as  about  15  per  cent.;  in 
fish  it  may  sometimes  rise  as  high  as  70  per  cent.  This  must 
certainly  be  taken  into  account  in  making  purchases  of  food.  In  the 
diagram  (Plate  III.)  allowance  has  been  made  for  these  waste 
matters,  but  no  account  has  been  taken  of  the  cost  of  cookery. 
This  is  a  matter  which  it  is  exceedingly  difficult  to  estimate,  as 
so  much  depends  upon  the  cook,  but  the  general  value  of  the  results 
is  not  seriously  impaired  by  the  omission. 

VlTAMINES.^ 

From  what  has  been  said  hitherto,  it  might  be  supposed  that  all 
that  is  necessary  to  constitute  a  normal  diet  is  a  sufficiency  of  protein, 
mineral  matter  and  water,  with  the  addition  of  enough  carbohydrate 
and  fat  to  supply  the  requisite  number  of  calories  to  make  good  the 
energy  requirements  of  the  body.  This,  however,  is  by  no  means 
the  case.  It  is  a  late  discovery  in  dietetics  that  no  diet  is  suited  to 
the  prolonged  maintenance  of  health  unless  it  also  contains  sub- 
stances of  doubtful  chemical  nature,  but  of  great  vital  importance, 
which  are  known  by  the  title  of  'vitamines.'  Our  knowledge  of 
the  vitamines — which  are  only  present  in  the  food  in  extremely 
minute  quantities — has  been  largely  acquired  by  a  study  of  the 
disease  beri-beri.  Careful  observation  of  this  disease  showed  that 
it  is  produced  by  the  consumption  of  a  diet  consisting  mainly  of 
'polished'  rice,  and  that  it  can  be  prevented  by  the  use  of  rice 
from  which  the  pericarp  has  not  been  removed.  These  observations 
were  confirmed  and  extended  by  the  study  of  an  analogous  condition 
produced  artificially  in  birds,  and  there  is  now  no  room  for  doubt 
that  the  husk  of  rice  contains  vitamines  the  absence  of  which 
induces  the  development  of  a  form  of  neuritis  known  clinically  as 
beri-beri.  Further,  it  has  long  been  known  that  scurvy  results  from 
a  diet  which  lacks  some  constituent  of  unknown  nature.  It  used  to 
be  believed  that  vegetable  salts  of  potash  were  the  ingredient  re- 
quired, but  the  observations  of  Axel  Hoist  ^  on  experimental  scurvy 
in  guinea-pigs  have  shown  that  here  also  we  are  dealing  with  a 
'  vitamine,'  although  a  different  one  from  that  concerned  in  beri- 
beri.    Not  only  can  definite  diseases   such   as   those   referred  to 

1  For  a  history  of  the  discovery  of  vitamines  and  of  the  growth  of  our  know- 
ledge relating  to  them,  see  'The  Nutritional  Importance  of  the  Presence  in 
Dietaries  of  Minute  Amounts  of  Certain  Accessory  Substances  '  (Brit.  Med. 
Journ.,  1913,  i.  722).  2  Brit.  Med.  Journ.,  1908,  ii.  1366. 


VITA  MINES  ig 

result  from  the  absence  of  vitamines,  but  there  is  also  now  reason  to 
believe,  as  the  result  of  the  researches  of  Hopkins^  and  others,  that 
normal  growth  requires  for  its  progress  the  presence  in  the  diet  of 
substances  of  a  similar  nature.  Hopkins  found,  for  instance,  that 
if  young  rats  are  fed  upon  a  diet  which  contains  the  proper  amount 
of  the  ordinary  nutritive  constituents,  but  which  has  been  'purified' 
by  extraction  with  alcohol,  growth  ceases,  but  is  at  once  resumed 
if  even  a  minute  amount  of  the  alcoholic  extract  is  added  to  the 
ration.  The  observations  of  Thompson^  upon  the  relatively  large 
gain  in  weight  which  may  follow  upon  the  addition  to  the  diet  of 
even  a  small  quantity  of  meat  extract  are  no  doubt  to  be  interpreted 
in  a  similar  way. 

As  to  the  exact  chemical  nature  of  the  vitamines  we  are  still 
much  in  the  dark.  They  are  probably  constituents  of  more  com- 
plicated molecules,  some  of  them  containing  phosphorus  (phospha- 
tides, nucleins),  and  some  of  them  may  be  of  the  nature  of  pyrimidine 
bases.  Their  mode  of  action  is  also  obscure,  but  they  appear  to 
serve  as  catalysts  or  activators,  which  exert  an  intermediary  influ- 
ence in  metabolism  and  render  possible  the  assimilation  of  certain 
nutrients,  probably  phosphorus  compounds.  More  definitely  than 
this  it  is  impossible  to  speak  in  the  present  state  of  our  knowledge, 
but  whatever  they  may  be,  we  know  that  the  vitamines  are  highly 
labile  substances,  which  are  easily  destroyed  by  heat,  drying,  or 
other  mechanical  processes.  Hence  the  ease  with  which  they  are 
removed  in  the  preparation  of  foods.  We  know  also  that  they  are 
only  represented  in  extremely  small  quantity  in  ordinary  food-stuffs, 
but  that  they  are  accumulated  in  relatively  much  greater  amount  in 
certain  articles,  such  as  the  pericarp  of  rice,  wheat,  and  other  cereals, 
the  brain,  heart  and  eggs  of  mammals  and  birds,  and  in  yeasts.  The 
antiscorbutic  vitamine  seems  to  be  specially  abundant  in  fresh 
vegetables  and  in  fruit  juices. 

Whether  any  diseases  other  than  those  mentioned  above  are  due 
to  the  absence  from  the  diet  of  specific  vitamines  we  do  not  know, 
but  it  seems  highly  probable.  It  has  been  suggested  that  pellagra, 
for  instance,  is  caused  by  the  absence  of  a  substance  normally 
present  in  the  whole  grain  of  maize,  but  this  has  not  yet  been 
proved,  though  there  is  much  evidence  in  favour  of  such  a  view. 
There  can  be  no  doubt,  however,  that  the  discovery  of  vitamines 
opens  up  an  entirely  new  field  in  dietetics,  and  that  in  the  light  of 
even  our  present  limited  knowledge  of  them  several  old  controversies, 
such  as  that  on  the  relative  nutritive  value  of  white  and  wholemeal 
bread  and  the  worth  of  beef-tea  as  a  food,  will  have  to  be  re-opened. 
*  Lancet,  1913,  ii.  1309.  ^  Brit.  Med.  Journ.,  191 1,  ii.  613. 


[20  J 


CHAPTER  II 

THE  AMOUNT  OF  FOOD  REQUIRED  IN  HEALTH 

It  was  pointed  out  in  the  last  chapter  that  the  function  of  food  is  a 
double  one:  (i)  to  furnish  material  for  bodily  growth,  and  for  the 
repair  of  the  daily  waste  of  the  tissues ;  (2)  to  provide  a  supply  of 
potential  energy  for  expenditure  in  the  form  of  heat  and  work.  We 
have  now  to  consider  how  much  food  must  be  supplied  daily  if  these 
functions  are  to  be  eflficiently  carried  out. 

It  will  be  convenient  to  consider  the  two  divisions  of  the  problem 
separately,  and  to  discuss  in  the  first  place  how  much  '  building 
material,'  in  the  second,  how  much  potential  energy,  is  required 
daily.  The  building  material  in  the  diet  consists,  as  we  have  seen, 
of  protein,  mineral  matters,  and  water.  I  propose  to  defer  to  a  later 
chapter  the  consideration  of  the  amount  of  mineral  matters  and 
water  which  the  diet  should  contain,  and  to  confine  myself  at  present 
to  the  discussion  of  the  question  : 

How  much  Protein  is  required  Daily  ?  —It  may  be  stated  at  once 
that  to  this  question  no  conclusive  reply  has  yet  been  furnished  by 
physiology.  This  is  unfortunate,  for  the  problem  is  one  the  import- 
ance of  which  it  would  be  impossible  to  exaggerate.  It  is,  indeed, 
one  of  the  most  fundamental  problems  in  the  physiology  of  nutri- 
tion, and  until  it  is  finally  solved  dietetics  cannot  fairly  claim  to 
rank  as  an  exact  science. 

In  the  succeeding  paragraphs  the  results  of  the  efforts  which  have 
been  made  to  settle  the  question  will  be  briefly  set  out. 

An  ordinary  man  on  a  freely- selected  diet  is  found  to  excrete 
about  20  grammes  of  nitrogen  daily.  It  may  be  assumed  that  all 
of  this  should  be  supplied  in  the  form  of  protein,  and  as  protein 
contains    about    16    per    cent,    of    nitrogen,    it    is    obvious    that 


AMOUNT  OF  PROTEIN  REQUIRED  ii 

125  grammes  of  the  former  will  be  able  to  supply  20  grammes  of 
the  latter.  As  a  matter  of  fact,  that  is  the  generally  accepted 
standard  for  the  amount  of  protein  required  daily,  but  it  is  by  no 
means  an  absolute  one.  The  reason  for  this  is  that  the  body  is  able 
to  establish  an  equilibrium  on  very  various  quantities  of  protein. 
The  typical  man  referred  to  above  excretes  20  grammes  of  nitrogen 
daily,  merely  because  he  consumes  that  amount  in  his  daily  food. 
Had  he  consumed  15  grammes,  he  would  only  have  excreted 
15  grammes,  and  if  his  consumption  had  risen  to  25  or  30  grammes 
or  higher,  his  excretion  would  still  have  kept  pace  with  it,  for  the 
body  is  unable  to  store  up  any  surplus  of  protein,  as  it  does  of 
carbohydrate  or  fat.  It  is  this  tendency  for  the  amount  of  nitrogen 
excreted  to  be  exactly  equal  to  the  amount  consumed  which  physi- 
ologists call  the  establishment  of  nitrogenous  eauilibrium,  and  it  is 
evident  that  such  equilibrium  can  be  established  on  any  quantity 
of  protein  which  the  digestive  organs  are  capable  of  dealing  with. 
The  question,  therefore,  is.  What  quantity  is  best  ?  To  this,  it 
may  be  at  once  confessed,  no  absolute  reply  can  be  given.  When 
one  recollects  that  the  chief  function  of  protein  is  to  keep  in  repair 
the  tissues  of  the  body,  one  is  tempted  to  suppose  that  all  that  is 
necessary  is  to  consume  enough  for  that  purpose.  Anything  above 
that,  it  might  be  thought,  would  be  mere  extravagance — the  liixus 
consumption  of  the  older  school  of  physiologists.  But  how  to  ascertain 
that  bare  amount  ?  The  reply  at  once  suggests  itself  that  in  the 
amount  of  nitrogen  excreted  during  starvation  there  will  be  found 
a  measure  of  the  amount  which  just  suffices  to  keep  the  tissues  in 
repair.  A  man  who  has  been  Carving  for  some  time  excretes 
about  4  to  5  grammes  of  nitrogen  daily, ^  but  it  is  found  that  if 
merely  this  amount  is  supplied  in  the  food  it  is  not  sufficient  to 
establish  equilibrium.  Indeed,  the  smallest  amount  of  nitrogen  on 
which  it  is  possible  to  establish  equilibrium  is  found  to  be  from 
three  to  four  times  the  amount  excreted  during  hunger.  Should 
we,  then,  attempt  to  live  on  this  minimum  ?  This  is  a  very 
difficult  question.  Remembering  that,  although  the  chief  use  of 
protein  is  to  build  up  and  repair  the  tissues,  yet  every  gramme  of  it 
is  also  capable  of  supplying  to  the  body  4-1  Calories  of  energy 
(p.  5),  it  is  evident  that  the  problem  which  confronts  us  can  be 
stated  in  another  way.  Should  we  make  use  of  protein  merely  as 
building  material,  relying  upon  carbohydrate  and  fat  as  our  sources  of 

*  For  observations  on  fasting  men,  see  'A  Digest  of  Metabolism  Experiments,' 
United  States  Department  of  Agriculture,  Bull.  45  (revised  edition),  p.  87,  1898. 


22  FOOD  AND  DIETETICS 

energy,  or  should  we  also  take  advantage  of  its  capability  of  pro- 
viding for  heat  and  work  ? 

Before  finally  replying  to  this  question  another  factor  in  the 
problem  must  be  presented.  We  know  from  physiological  experi- 
ment that  the  greater  the  quantity  of  carbohydrate  and  fat  which 
is  supplied  along  with  protein,  the  less  does  the  latter  tend  to  be 
wasted  in  supplying  energy,  and  the  more  of  it  there  is  available 
for  the  higher  purpose  of  keeping  the  tissues  in  repair.  The  fat 
and  carbohydrate  are  sacrificed  instead  of  the  protein.  This  is 
what  physiologists  mean  when  they  describe  fats  and  carbohydrates 
as  protein  sparers.  But  it  is  almost  impossible  so  to  arrange 
matters  that  all  the  energy  shall  come  from  fat  and  carbohydrate, 
and  so  leave  all  the  protein  free  for  repairing  the  fabric  of  the  body. 
And  for  this  reason :  the  cells  of  the  body  may  be  supposed  to  be 
bathed  with  lymph  containing  in  solution  particles  of  protein,  fat, 
and  carbohydrate  derived  from  the  blood.  These  particles  are 
attacked  by  the  cells  and  oxidized,  heat  and  energy  being  liberated 
in  the  process.  But  the  cells  do  not  seem  to  be  able  to  attack  each 
of  these  constituents  with  equal  ease.  Of  the  three  constituents 
mentioned,  protein  is  most  easily  broken  down,  then  carbohydrate, 
fat  least  easily  of  all.  If,  then,  the  three  are  present  in  equal  pro- 
portion, there  will  always  be  more  of  the  protein  attacked  than  of 
the  others.  But  if,  on  the  other  hand,  carbohydrate  and  fat  are 
present  in  great  excess,  they  assert  themselves  by  their  mere  '  mass 
influence,'  and  exclude  many  of  the  protein  particles  from  ever 
coming  into  contact  with  the  cell  at  all — crowding  them  out,  so  to 
speak — and  so  sparing  the  protein  from  destruction.  It  is  almost 
impossible,  however,  to  get  the  three  chief  nutritive  constituents  into 
the  neighbourhood  of  the  cell  in  such  proportions  that  none  of  the 
easily-attacked  protein  is  used  up.  By  giving  abundance  of  carbo- 
hydrate this  object  can  be  more  easily  effected  than  by  fat,  for,  as 
we  have  seen,  the  cells  have  less  difficulty  in  coping  with  the  former 
than  the  latter.  Gelatin  is  an  even  more  efficient  sparer  of  protein 
(see  p.  77).  Hence  it  is  that  those  foods  which  contain  a  very  large 
excess  of  carbohydrate  along  with  a  moderate  proportion  of  protein, 
and  in  which  both  are  absorbed  Eind  reach  the  cells  at  about  the 
same  rate — a  most  important  point — will  be  the  foods  on  which 
least  protein  is  likely  to  be  wasted  and  the  largest  fraction  of  it 
reserved  for  tissue  repair.  In  other  words,  these  will  be  the  foods 
to  have  recourse  to  if  one  wishes  to  preserve  nitrogenous  equilibrium 
on  a  minimum  amount  of  protein.  In  accordance  with  this,  it  has 
been  found  that  nitrogenous  equilibrium  can  be  maintained  on  1,500 


AMOUNT  OF  PROTEIN  REQUIRED  23 

to  1,600  grammes  of  bread  containing  only  104  grammes  of  protein, 
on  800  grammes  of  maize  with  74  of  protein,  and  on  3,080  grammes 
of  potatoes  in  which  the  total  protein  amounts  to  not  more  than 
54  grammes ;  and  yet  all  of  these  quantities  are  sufficient  to  supply 
3,000  Calories  daily  (Rubner). 

Despairing  of  finding  any  reply  to  the  question  What  is  the 
protein  optimum  ?  on  purely  scientific  grounds,  physiologists  have 
had  recourse  to  two  other  methods  of  attacking  the  problem — viz., 
(i)  by  estimating  the  amount  of  protein  contained  in  the  freely- 
chosen  diet  of  an  average  man  doing  a  moderate  amount  of  muscular 
work  ;  (2)  by  testing  experimentally  the  point  to  which  the  amount 
of  protein  in  the  diet  can  be  reduced  without  any  impairment  of  the 
health  and  efficiency  of  the  individual  resulting. 

(i)  The  former  of  these  methods  was  first  employed,  and  upon  its 
results  the  accepted  dietary  standards  have  hitherto  been  based. 
Any  estimate  of  its  validity,  however,  must  depend  upon  the  number 
and  extent  of  the  data  upon  which  its  conclusions  are  founded,  and 
upon  one's  belief  in  the  instinctive  wisdom  of  mankind  in  matters  of 
food.  To  the  trustworthiness  of  its  data,  I  think,  no  reasonable 
objection  can  be  taken.  A  very  large  number  of  analyses  of  freely- 
chosen  diets  in  various  parts  of  the  world  have  now  been  made 
(see  p.  32),  and  they  show,  with  a  remarkable  degree  of  unanimity, 
that  the  standard  of  protein  adopted  has  been  almost  invariably 
something  above  100  grammes.  Where  the  standard  falls  below 
this  the  shortcoming  is  explicable  either  on  the  ground  of  insufficiency 
of  means  to  purchase  the  average  diet,  or,  as  in  the  case  of  some 
Asiatics,  by  reason  of  the  subject  being  an  individual  of  small  body- 
weight. 

The  objection,  on  the  other  hand,  that  this  standard,  though 
nearly  universal,  is  not  necessarily  wise,  cannot  be  met  so  easily, 
and  its  force  will  depend  upon  the  relative  weight  which  one  attaches 
to  instinct  and  to  greed  respectively,  in  determining  the  dietetic 
habits  of  mankind.  For  his  own  part,  the  writer  is  bound  to  point 
out  that  there  is  at  least  strong  a  priori  reason  for  the  belief  that,  in 
matters  of  diet,  what  has  been  adopted  semper  et  tibigue  et  ab  omnibus 
is  fundamentally  right,  especially  when  one  remembers  that  protein 
is  one  of  the  more  expensive  nutritive  constituents  of  the  food,  which 
it  must  often  involve  a  good  deal  of  struggle  and  sacrifice  to  obtain. 

(2)  Although  certain  individual  vegetarians,  and  even  vegetarian 
races,  have  for  long  been  unconsciously  employing  the  second  method 
of  attacking  the  problem  of  the  protein  optimum,  Chittenden  was 
the  first  to  use  it  deliberately  and  experimentally  on  a  sufficiently 


24  FOOD  AND  DIETETICS 

large  scale,  and  under  rigid  scientific  conditions.  His  results 
showed  1  that  in  groups  of  professional  men,  athletes,  and  soldiers, 
nitrogenous  equilibrium,  health,  and  efficiency  could  be  maintained 
for  periods  of  some  months  on  a  daily  intake  of  protein  of  less  than 
60  grammes,  or  about  half  that  contained  in  most  freely  chosen 
diets. 

Chittenden  and  his  followers  do  not  shrink  from  the  logical  con- 
clusion of  these  experiments.     They  believe  that  the  protein  standard 
of  120  grammes,  which  has  been  accepted  ever  since  Voit  first  set  it 
up,  is  far  too  high,  that  it  is  wasteful  economically,  and,  not  only  so, 
but  injurious  to  health,  by  throwing  upon  the  organs  of  digestion, 
assimilation,  and  excretion  an  unnecessary  amount  of  work.    It  need 
hardly  be  said  that  the  champions  of  the  orthodox  standard  have  not 
been  backward  in  subjecting  Chittenden's  experiments,  and  the  con- 
clusions founded  upon  them,  to  criticism,  and,  apart  from  technical 
questions  as  to  his  methods,  the  following  summary  of  objections  to 
the  general  adoption  of  a  low  protein  standard  may  be  stated  : ' 
{a)  Although   such   a   standard   may  be   adopted  with  apparent 
impunity  for  a  period  amounting  even  to  several  months,  it 
does  not  follow  that  it  can  be  safely  pursued  for  years.     The 
vemote  consequences  in  a  lowered  resistance  to  disease  and 
in  general  diminution  of  tone  might  well  be  injurious.     As 
Rubner  has  put  it,^  the  excess  of  protein  in  the  ordinary 
diet  is  to  be  regarded  as  a  margin  of  safety,  just  as  one 
builds  a  bridge  considerably  stronger  than  is  necessary  for 
the  maximum  load  it  has  to  carry. 
(Jb)  There  is  reason  to  believe  that  persons  who  are  accustomed  to 
ingest  but  little  protein  are  unable  to  assimilate  an  increased 
amount  when  necessary.     In  wasting  diseases  and  in  con- 
valescence this  would  prove  harmful. 
{c)  The  attempt  to  carry  on  life  upon  a  minimum  of  protein  may 
result  in  a  loss  of  nitrogenous  substaxice  from  the  body  in 
slight  and  temporary  disturbances  of  health,  which  it  may 
take  weeks  to  replace. 
{d)  If  hard  work  is  done  on  a  small  protein  intake,  the  necessary 
energy  can  only  be  obtained  by  increasing  the  supply  of  fat 

1  See  *  Physiological  Economy  in  Nutrition.'  New  York  :  Frederick  A.  Stokes 
Co.,  1904.  and  ' The  Nutrition  of  Man.'     London:  Wm.  Heinemann,  1907. 

2  For  an  able  discussion  of  the  whole  question  see  Sir  James  Crichton  Browne's 
'Parsimony  in  Nutrition'  (London  and  New  York:  Funk  and  Wagnalls  Co-X 
1909  ;  and  for  detailed  criticism  of  Chittenden's  methods  see  Benedict,  Amer. 
Journ.  of  Phys.,  1906,  xvi.   409. 

•  '  Volksernahrungs-Fragen,"  p.  41. 


AMOUNT  OF  PROTEIN  REQUIRED  25 

and  carbohydrates  to  a  point  which  may  be  greater  than  the 
digestive  organs  can  comfortably  stand. 
(<f)  The  assertion  that  the  prevalent  protein  standard  is  injurious 
to  health  is  based  upon  insufficient  evidence,  and  is  opposed 
to  universal  experience. 

Here,  for  the  present,  we  must  leave  the  question,  although  we 
shall  return  to  its  discussion  later  on  (p.  173).  Whether  the  old 
standard  of  120  grammes  or  the  new  one  of  60  grammes  is  better 
time  alone  can  show.  '  The  truth  is  great  and  will  prevail.'  It  is 
only  by  the  adoption  of  the  lower  standard  by  a  sufficiently  large 
number  of  individuals  in  varied  circumstances,  and  over  a  long 
period  of  time,  that  the  desirability  of  its  general  adoption  can  be 
proved  ;  and  owing  to  the  great  interest  which  Chittenden's  work  has 
aroused,  there  can  be  little  doubt  that  such  evidence  will  one  day  be 
forthcoming.  Meanwhile  this  must  be  said  :  that  whatever  may 
prove  to  be  good  for  an  ordinary  adult,  there  can  be  no  question  that 
in  the  case  of  children,  adolescents,  and  pregnant  women,  it  is  far 
safer  to  adopt  a  Irigh  protein  standard  than  a  low  one.  No  risk 
must  be  run  of  providing  an  insufficiency  of  material  for  the  complete 
building  up  of  the  growing  organism. 

We  may  now  turn  to  the  other  division  of  our  problem,  and  ask  : 

How  MUCH  Potential  Energy  should  the  Diet  contain? 

This  question,  being  purely  one  of  physics,  is  much  more  easily 
capable  of  exact  solution,  and  fortunately  the  reply  given  to  it  by 
physiologists  is  fairly  definite  and  unanimous.  The  data  necessary 
for  its  solution  may  be  obtained  in  two  ways.  There  is  first  what 
one  may  call  the  purely  physiological  vieihod.  A  man  is  shut  up  in  a 
respiration-calorimeter.  All  the  heat  which  he  gives  out  from  his 
body  in  a  given  time  is  measured,  and  the  work  which  he  does  is 
also  measured  and  expressed  in  terms  of  heat.  The  result  stated  in 
the  form  of  Calories  gives  the  amount  of  energy  which  has  been 
expended  by  the  body  in  a  given  time,  and  consequently  the  amount 
of  potential  energy  which  must  be  supplied  in  the  form  of  food  to  main- 
tain equilibrium.  Such  a  method  is  necessarily  very  laborious,  and 
only  a  limited  number  of  observations  by  it  are  yet  available,  most 
of  which  have  been  made  in  America;^  but  there  can  be  no  doubt 
that  it  will  be  much  more  largely  employed  in  the  future.  The 
results  yielded  by  this  method,  when  translated  into  quantities  of 
ordinary  food-stuffs,  form  the  basis  of  standard  dietaries. 

*  See  Bull.  109,  United  States  Department  of  Agriculture  (Off.  of  Experiment 
Stations),  1902. 


I* 

26  FOOD  AND  DIETETICS 

By  far  the  larger  number  of  observations  have  been  made  by 
what  may  be  called  the  empirical  method.  A  healthy  individual 
living  under  known  conditions,  and  on  a  freely-chosen  diet,  is 
selected ;  the  food  which  he  eats  and  the  excreta  given  off  from 
his  body  are  analyzed,  and  in  this  way  one  discovers  whether  or 
not  the  income  in  diet  is  equal  to  the  expenditure  as  represented 
by  the  waste  products  excreted  and  the  state  of  the  individual's 
weight.  The  method  may  be  modified  by  varying  the  diet  in 
different  directions,  and  seeing  how  each  change  affects  the  balance- 
sheet  of  the  body,  or  groups  of  persons  living  under  similar  condi- 
tions may  be  chosen  instead  of  individuals,  and  the  average  amount 
of  food  required  calculated  from  the  total  consumed  by  the  group. 
Such  observations  have  mostly  been  made  on  the  inmates  of  public 
institutions.  From  the  data  yielded  by  this  method  actual  dietaries 
can  be  drawn  up,  some  examples  of  which  will  be  given  imme- 
diately. A  study  both  of  standard  and  actual  dietaries  shows  that 
a  man  of  average  weight  (11  stones),  and  doing  a  moderate  amount 
of  muscular  work,  must  be  supplied  daily  with  an  amount  of 
energy  in  the  form  of  food  which  is  the  equivalent  of  about  3,000 
Calories.^ 

We  have  now  to  ask,  What  proportion  of  this  total  should  be 
supplied  in  the  form  of  protein,  carbohydrate,  and  fat  respectively  ? 
As  regards  protein,  we  have  already  seen  that  the  amount  recom- 
mended by  most  physiologists  is  120  grammes  daily,  which  would 
yield  about  15  per  cent,  of  the  total  energy  required.  We  have  only 
to  consider  the  remaining  question — 

How  MUCH  Carbohydrate  and  Fat  should  the  Diet  contain  ? 

As  far  as  the  demand  of  the  cells  for  energy  is  concerned,  it  is 
probably  a  matter  of  indifference  how  much  of  the  total  energy 
required  is  obtained  in  each  of  these  forms,  provided  one  remembers 
always  that  it  takes  2|-  parts  of  carbohydrate  to  supply  as  many 
Calories  as  i  part  of  fat.  To  the  digestive  organs,  however,  it  is  by 
no  means  a  matter  of  indifference.  If  all  the  energy  not  provided  as 
protein  were  to  be  supplied  in  the  form  of  carbohydrate,  it  would 
mean  that  a  large  hdk  of  food  must  be  consumed,  which  would  be 
not  only  apt  to  overload  the  stomach  and  intestines  by  its  mere 
weight,  but  would  also  be  prone  to  undergo  fermentation,  leading  to 
the  production  of  flatulence  and  acidity.     If,  on  the  other  hand,  fat 

*  According  to  Chittenden  {op.  cit.),  this  is  considerably  in  excess  of  the  amount 
actually  required  by  a  man  doing  only  moderate  muscular  work. 


FAT  AND  CARBOHYDRATE  REQUIRED  27 

be  adopted  as  the  exclusive  source,  one  would  run  the  risk  of  over- 
stepping the  limits  of  fat  absorption,  and  nausea,  and  probably 
diarrhoea,  would  ensue.  In  this  matter  habit  and  personal  peculi- 
arity have  a  great  influence.  There  are  some  races,  such  as  the 
Esquimaux,  who  take  almost  the  whole  of  their  energy  in  the  form 
of  fat ;  others  take  it  mainly  in  the  form  of  carbohydrates.  The 
Scotsman  is  notoriously  less  incHned  to  eat  fat  than  the  Englishman, 
and  one  constantly  meets  with  individuals  who  have  an  insuperable 
repugnance  to  the  consumption  of  even  moderate  amounts  of  fat. 
We  have  already  seen  that  150  grammes  of  fat  can  be  absorbed 
daily  without  much  difficulty,  but  in  most  persons  anything  above 
100  grammes  (3^  ounces)  in  winter,  and  rather  less  in  summer, 
would  be  apt  to  produce  disorders  of  digestion.  For  this  reason 
alone,  therefore,  it  is  well  to  take  a  mixture  of  carbohydrate  and  fat 
rather  than  either  of  these  exclusively,  and  50  grammes  of  fat 
( =  2^  ounces  of  butter)  to  500  of  carbohydrate  ( =  i  pound  2  ounces 
of  sugar)  may  be  regarded  as  a  reasonable  proportion.  This 
is  in  the  ratio  of  i  part  of  fat  to  10  of  carbohydrate.  Many 
authorities,  however,  recommend  more  of  the  former  and  less  of  the 
latter. 

Some  direct  observations  on  this  point  were  made  by  Forster^  on 
the  actual  dietaries  of  different  individuals.  He  found  that  to  every 
part  of  fat  the  following  amounts  of  carbohydrate  were  consumed  : 


Subject.  Carhohydyate. 

Infant        . .  . .  . ,  1-4 

Child  of  five  months  . .         1-4 

Labourer's  child  ..         5-6 

Well-to-do  adult  ..         34 


Subject.  Carbohydrate. 

Labourer..         ..  ..         5*0 

Old  man  ..         . .  . .         5"i 

Old  woman  ..  ..         5-3 

Nursing  woman . .  ..         2*4 


The  results  show  that  in  every  case  investigated  the  quantity  of 
fat  obtainable  was  considerably  greater  than  the  amount  fixed  in 
the  standard. 

The  question  of  expense  also  comes  in  here.  Fat  is  a  dear  but 
compact  form  of  energy ;  carbohydrate  is  bulky  but  cheap.  Those 
who  can  afford  it  usually  try  to  get  the  advantages  of  a  condensed 
food,  in  spite  of  its  greater  cost ;  while  those  to  whom  pecuniary 
considerations  are  of  importance  must  put  up  with  the  inconveniences 
of  the  more  bulky  food  in  exchange  for  its  greater  cheapness. 

Hence  one  finds  that,  as  a  matter  of  observation,  the  food  of  the 
rich  is  usually  much  more  fatty  than  that  of  the  poor. 

Opportunity,  also,  is  a  determining  factor.  The  Esquimaux  eats 
much  fat  because  he  cannot  grow  crops ;  the  Hindoo  consumes 
much  carbohydrate  because  he  has  got  facilities  for  growing  rice. 

1  Pettenkofer  and  Ziemssen's  'Handbuch  der  Hygiene,'  1882,  Bd.  L,  p.  137. 


28  FOOD  AND  DIETETICS 

Here,  as  in  so  many  other  cases,  necessity  determines  the  choice, 
and  custom  makes  it  the  most  agreeable. 

Notwithstanding  the  above  considerations,  to  which  the  practical 
solution  of  the  question  must  usually  be  left,  it  is  still  of  some 
scientific  interest  to  ask  whether  there  may  not  be  some  part  played 
in  the  body  by  fat  which  is  not  so  well  fulfilled  by  carbohydrates, 
and  vice  versa.  There  is  not  much  in  the  way  of  experimental 
evidence  to  help  us  in  coming  to  a  conclusion  on  this  point,  but 
there  is  a  prevailing  belief  among  competent  observers  that  in  the 
diet  of  children,  at  least,  a  deficiency  of  fat  cannot  be  replaced  by  an 
excess  of  carbohydrate,  and  that  fat  seems  to  play  some  part  in  the 
formation  of  young  tissues  which  cannot  be  undertaken  by  any  other 
nutritive  constituent  of  food.*  The  association  of  rickets,  especially, 
with  a  deficiency  of  fat  in  the  diet  seems  to  be  pretty  fkmly  estab- 
lished. An  attempt  has  been  made^  to  put  this  belief  to  the  test 
of  exact  experiment  by  feeding  young  pigs  on  milk  from  which 
almost  the  whole  of  the  fat  had  been  removed  by  a  separator.  It 
was  found,  however,  that  the  animals  so  fed  did  not  become  rickety, 
nor  did  the  fatty  matter  which  is  so  abundantly  present  in  the  central 
nervous  system  undergo  any  diminution.  On  the  other  hand,  the 
subcutaneous  fat  almost  entirely  disappeared,  and  was  replaced  by  a 
gelatinous  sort  of  connective  tissue.  The  curious  fact  was  also 
observed,  that  the  deficiency  of  fat  in  the  food  led  to  an  interference 
with  the  absorption  of  phosphorus,  although  no  explanation  of  this 
is  advanced.  If  a  large  excess  of  carbohydrate  was  supplied,  it  was 
found  that  the  subcutaneous  fat  did  not  undergo  such  marked 
diminution.  It  must  be  admitted  that  the  belief  that  fat  is  necessary 
for  the  formation  of  new  tissues  receives  but  little  confirmation  from 
this  experiment. 

One  point  in  which  fat  is  not  able  to  replace  carbohydrate  in  its 
dynamic  equivalent  is  in  protein-sparing  power.  In  this  direction 
I  part  of  fat  is  not  as  efficient  as  2^  parts  of  carbohydrate.'  If, 
therefore,  the  proportion  of  fat  in  the  diet  be  increased,  the  amount 
of  protein  consumed  must  also  be  increased.  An  examination  of 
freely-chosen  diets  shows  that  this  is  actually  done. 

One  may  sum  up  in  round  numbers  the  standard  amounts  of  the 
different  nutritive  constituents  required  daily  thus ; 

1  See,  for  example,  Cheadle,  'Artificial  Feeding  and  Food  Disorders  of 
Infants  '  (London  :  Smitfi,  Elder  and  Co.),  p.  12. 

2  Journal  of  Experimental  Medicine,  1898,  iii.  293. 

*  See  Von  Noorden,  '  Pathologic  des  Stoffwechsels,'  p.  117.  Wickeand  Weiske 
{Zeits.  f.  physioL  Chemie,  1895,  xxi.  42,  and  1896,  xxii.  137)  found  that  100  grammes 
of  starch  diminished  protein  katabolism  19  to  21  per  cent.  ;  a  similar  weight  of 
fat  diminished  it  by  30  to  40  per  cent.  ;  t'.^.,  the  absolute  effect  of  fat  is  greater 
than  that  of  carbohydrate,  but  the  relative  effect  is  less. 


NUTRITIVE  RATIO  9g 

Protein 120  grammes. 

Carbohydrate      ..         ..  ..  ..     500        ,, 

Fat  50        „ 

The  energy  value  of  such  a  diet  is  close  upon  3,000  Calories. 

Such  a  standard  may  be  regarded  as  suitable  for  a  man  of  average 
build  and  weight,  leading  an  active  life  and  doing  a  fair  amount  of 
muscular  work,  and  if  a  greater  intake  of  energy  is  demanded,  it 
should  be  met  by  increasing  the  amount  of  fat  consumed. 

In  the  following  table  I  have  collected  similar  standards  fixed  by 
others : * 


Authority. 

Protein. 

Fat. 

Carbohydrate. 

Calories. 

Munk 

105 

56 

500 

3,022 

Wolff         

125 

35 

540 

3.030 

Voit            

118 

56 

500 

3.055 

Rubner 

127 

52 

509 

3.092 

Playfair 

119 

51 

531 

3,140 

Moleschott 

130 

40 

550 

3,160 

Atwater 

125 

125 

45« 

3.520 

Average     , . 

121 

59 

510 

3.135 

It  will  be  observed  that  the  chief  point  of  divergence  is  in  the 
relative  proportion  of  carbohydrate  and  fat ;  the  amount  of  protein 
is  very  similar  in  all.  The  total  Calories  yielded  is  remarkably 
constant,  despite  these  divergencies.  It  should  also  be  stated  as 
regards  that  point  that  in  these  standards  no  account  is  taken  of  the 
inevitable  loss  resulting  from  incomplete  absorption  of  the  con- 
stituents. To  allow  for  this,  the  total  Calories  yielded  would  require 
to  be  reduced  in  each  case. by  about  200.  In  the  latest  American 
standard  (Langworthy)  the  loss  both  from  waste  material  in  the 
food  as  purchased  and  from  non-absorption  is  allowed  for  thus : 

DIETARY  STANDARD  FOR  MAN  IN  FULL  VIGOUR  AT 
MODERATE  MUSCULAR  WORK. 


Protein. 


Food  as  purchased 
Food  eaten 
Food  digested 


Energy. 


Grammes. 


100 
95 


Calories. 
3,800 
3: 500 
3,200 


In  such  Standards  the  ratio  of  protein  to  carbohydrates  and  fat 
taken  together  is  of  some  importance.  It  is  called  the  nutritive 
ratio.     If  I  part  of  fat  be  counted  as  2^  parts  of  carbohydrate,  the 

^  Chittenden's  standard  has  not  been  included,  but  it  may  be  taken  as 
60  grammes  of  protein,  and  a  total  fuel  value  of  2.800  Calories.  He  has  not 
attempted  to  fix  the  proportion  af  fat  and  carbohydrate. 


30  FOOD  AND  DIETETICS 

nutritive  ratio  in  the  average  of  the  above  standards  is  as  i  to  5-3. 
In  this  ratio  we  have  an  index  of  the  proportion  which  the  building 
material  of  the  diet  ought  to  bear  to  its  purely  energy-yielding 
constituents. 

It  need  hardly  be  remarked  that  we  do  not  consume  our  food  in 
the  form  of  pure  protein,  carbohydrate,  and  fat.  If,  therefore,  the 
above  conclusions  are  to  be  of  any  practical  value,  they  must  be 
translated  into  terms  of  ordinary  articles  of  diet. 

Necessity  for  a  INIixed  Diet. 

In  the  first  place  it  may  be  remarked  that  no  one  article  of 
food  contains  the  different  nutritive  constituents  in  proper  pro- 
portions. 

Some  foods  are  too  rich  in  protein  ;  others  contain  too  much 
carbohydrate  or  fat.  The  former  statement  is  true  of  all  animal 
foods,  and,  amongst  the  vegetable  foods,  of  such  articles  as  dried 
peas,  beans,  and  lentils.  Most  other  vegetable  foods,  on  the  con- 
trary, of  which  bread  and  potatoes  may  be  taken  as  types,  contain 
an  excess  of  carbohydrates. 

The  practical  outcome  of  this  is  that  a  proper  diet  must  be  a 
mixed  one,  the  excess  of  a  particular  element  in  one  article  being 
played  ofT  against  its  deficiency  in  another.  People  have  found  this 
out  for  themselves  by  experience  ;  hence  the  popularity  of  such 
combinations  as  bread  and  cheese,  bacon  and  beans,  or  potatoes  and 
beef,  in  which  the  surplus  of  carbohydrate  or  fat  in  the  first  article 
is  made  up  for  by  the  excess  of  protein  in  the  second.  In  a  similar 
way  we  strike  a  proper  balance  in  puddings  by  compounding  them 
of  articles  rich  in  protein  on  the  one  hand,  such  as  eggs  and  milk, 
with  articles  containing  a  surplus  of  carbohydrate  on  the  other,  such 
as  rice  or  bread.  The  use  of  white  sauce  with  fish  is  an  example  of 
a  similar  adaptation. 

That  mankind  is  right  in  so  doing  is  borne  out  by  the  disastrous 
results  which  have  followed  attempts  to  live  for  any  length  of  time 
on  a  single  article  of  diet. 

Hammond^  tried  to  live  on  a  daily  ration  of  a  pound  and  a  half  of 
starch,  along  with  water.  He  had  to  abandon  the  experiment  on 
the  tenth  day,  owing  to  the  onset  of  debility  and  fever.  On  another 
occasion  he  attempted  to  live  on  nothing  but  albumin.  After  nine 
days  diarrhoea  and  albuminuria  supervened,  and  the  experiment  had 
to  be  given  up. 

1  'Transactions  of  the  American  Medical  Association,  1S57,'  x..  p.  511. 
For  similar  experiments  see  Flint's  '  Physiology  of  Man,'  1867,  ii.,  p.  128. 


STANDARD  DIETARIES 


31 


The  following  table  represents,  with  some  modifications,  standard 
daily  dietaries  constructed  by  Atwater  : 

STANDARD  DIETARIES. 

Daily  Dietaries. — Food  materials  furnishing  approximately  the  0  28  pound  {=125  grammes) 
of  protein  and  3,500  Calories  of  energy  of  the  standard  for  daily  dietary  of  a  man  at 
moderate  muscular  work. 


Amount. 

Cost. 

Nutritive  Constituents. 

Fuel 
value. 

Food  Materials. 

Total 
Organic 
Matter. 

Protein. 

Fats. 

Carbo- 
hydrates. 

I. 

Beef,  round  steak    . . 

Butter 

Potatoes 

Bread 

Ounces. 
13 
3 
6 

22 

s.    d. 
0    6 

0    3 
0    oj 
0     24 

Pauftr^s. 
•26 
•16 
■17 
•89 

Pounds. 
•14 

•02 

'12 

Pounds. 
■12 
•16 

•02 

Pounds. 

■is 
•75 

Calories. 

695 

680 

320 

1,760 

44 

I     0 

1-48 

•28 

■30 

•90 

3.455 

11. 
Pork,  salt 
Butter 

Beans 

Bread  ..         „ 

4 
2 

16 
8 

0     li 
0    2 

0       2^ 
0       I 

•21 
•11 
•84 
•33 

•23 
•04 

■21 
'11 
•02 
"OI 

■59 
•28 

880 

450 

1,615 

640 

30 

0    7 

1-49 

■27 

•35 

•87 

3.585 

III. 

Beef,  neck      . . 

Butter 

Milk,  T  pint   .. 

Potatoes 

Oatmeal 

Bread 

Sugar 

10 

I 

16 
16 
.  4 
16 

3 

0     2i 

0    I 

0       2 
0       I 
0       I 
0       2 

0    oj 

■•9 
■05 
•13 
■17 
■23 
•67 
•19 

•lo 

■04 
•02 

•04 

•09 

•09 

■OS 
•04 

■02 
•02 

■05 

•is 
■17 
■56 
■19 

550 
225 
32s 

460 

I,2So 

345 

66 

0    10 

1-63 

•29 

•22 

I'I2 

3.50s 

IV. 

Beef,  upper  shoulder 

Ham 

Two  eggs 

Butter 

Milk,  I  pint  . . 

Potatoes 

Flour 

Sugar 

10 
6 
3 
2 
16 
12 

9 

I 

0    3J 
0     3 
0     2 
0     2 
0     2 
0     0: 
0     0:; 

0      O;: 

22 

19 
05 
II 

13 
12 

44 
06 

•09 
•06 
■03 

■04 
•01 

■OS 

■13 
•'3 
•02 
■11 
•04 

•01 

•OS 

"IT 

•38 
•06 

800 
650 
135 
450 
32s 
240 
825 
"5 

59 

I  2i 

1-32 

•28 

■44 

■60 

3.540 

V. 

Sausage 

Cod-fish 

Butter 

Milk,  I  pint   .. 

Beans 

Rice 

Potatoes 

Bread 

Sugar 

4 
14 
2 

16 
5 
2 

16 
9 
3 

0  li 

0    3i 
0    2 
0    2 

0       Oi; 
0       0 
0       I 
0       I 

0     oj 

■14 
•07 
■ji 
■13 
•26 
"11 
■24 
■33 
■19 

•03 

•07 

•04 
•07 
■qi 
■01 

•04 

•n 

■11 

•04 
•01 

■01 

■05 
•18 
•10 
•23 
•28 
■19 

510 
140 

450 
32s 
50s 
20s 
420 
640 
345 

71 

I     of 

1-58 

•27 

•28 

T03 

3.540 

VL 

Beef 

Mackerel,  salt 

Two  eggs 

Butter 

Cheese 

Milk,  I  pint  .. 

Potatoes 

Rice 

Bread 

Sugar 

8 
4 

k 
I 
16 
8 
2 

0     3 
0     ij 
0    2 

0    oi 
0    2 
0     oi 
0    oj 
0    I 
0    oj 

18 
08 
05 
13 
04 

t3 
09 
II 

38 
69 

•08 
■04 
•03 

•02 

■04 

"or 
■01 

•05 

•10 

•04 
•02 

■13 
■02 

■04 
•01 

■oS 
•08 
•10 
■32 
•09 

s6o 
230 
135 
56s 
130 

IZ 

20s 
720 

175 

55 

I    li 

1-88 

■28 

•36 

•64 

3.205 

The  prices  given  in  this  table  are  those  which  rule  in  America.     They  are  not  always  the  same 
a&  those  in  this  country,  but  the  value  of  the  figures  is  not  really  affected  thereby. 


3^ 


FOOD  AND  DIETETICS 


It  is  worth  while  noticing,  incidentally,  the  relative  cost  of  these 
diets.  Compare,  for  example,  in  this  respect,  No.  II.  with  No.  IV. 
Both  of  these  contain  practically  the  same  amount  of  nutriment,  but 
the  latter  costs  exactly  twice  as  much  as  the  former.  This  is  a  fresh 
proof  of  the  fact  which  has  already  been  insisted  upon,  that  the  cost 
of  a  diet  is  no  indication  of  its  nutritive  value. 

The  total  weight  of  dry  food  which  is  consumed  daily  in  such  a 
standard  diet  as  any  of  the  above  is  about  23  ounces  (or  almost 
I  ounce  per  hour).  This  represents  45  ounces  (nearly  3  pounds)  of 
ordinary  food. 

Actual  Dietaries. 

The  standard  dietaries  given  above  are  constructed,  as  we  have 
seen,  from  theoretical  data.  It  is  interesting  to  compare  with  them 
the  composition  of  the  ordinary  diets  actually  consumed  by 
individuals  of  different  countries  and  diflferent  social  rank.  In  the 
following  table  (also  modified  from  Atwater)  a  large  number  of 
such  dietaries  have  been  collected  : 


ACTUAL   DIETARIES. 


Classes. 


1.  Sewing- girl,    London,    wages    3s.    gd.    per 

week 

2.  Factory  girl,  Leipsic,  Germany,  wages  ss.  per 

week 

3.  Weaver,  England,  time  of  scarcity^    . . 

4.  Labourers,    Lombardy,     Italy ;    diet    mostly 

vegetable  . .  . .  . .  . .  •  • 

5.  Trappist  monk  in  cloister ;  very  little  exercise, 

vegetable  diet    . . 

6.  Students,  Japan     .. 

7.  University    professor,     Munich,     Germany ; 

very  little  exercise 

8.  Lawyer,  Munich   . . 

9.  Physician,  Munich 

10.  Painter,  Leipsic,  Germany 

11.  Cabinet-maker,  Leipsic,  Germany 

12.  '  Fully-fed  '  tailors,  England     .. 

13.  'Well-paid' mechanic,  Munich,  Germany     .. 

14.  Carpenter,  Munich.  Germany   .. 

15.  '  Hard-worked  '  weaver,  England 

16.  Blacksmith,  England 

17.  Miners  at  very  severe  work,  Germany 

18.  Brick  -  makers  (Italians   at   contract    wcjrk), 

Munich    . . 

19.  Brewery  labourer,  Munich  ;  very  severe  work, 

exceptional  diet 

20.  Gernuan  soldiers,  peace  footing 
ai.  German  soldiers,  war  footing    . . 

at.  German  soldiers,  Franco-German  War  ;  extra- 
ordinary ration 
83.   Russian  workmen 

34.  Swedish  workmen  (moderate  labour)  . . 
25.  Swedish  workmen  (hard  labour) 


Nutritive  Constitubnts. 


Protein. 


Grms. 


97 

100 

80 
131 
87 
77 
131 

151 
131 

151 
176 
133 

167 

223 
114 
134 

157 
132 
134 
189 


Fats. 


Grms. 


100 

125 

95 
69 
57 
39 
54 
68 
43 
71 
"3 


"3 
39 

S8 

285 
80 

79 
no 


Carbo- 
hydrates. 


Grms. 


3-6 

301 
398 

362 

469 
438 

240 

222 

327 
366 
466 
525 

479 
494 
622 
667 
634 

675 

909 

480 
489 

331 
583 
523 
7'4 


ToUl. 


402 

406 
486 

484 

548 
551 

44° 
427 

553 
522 
600 

695 
684 
69.^ 
816 


i>245 

633 
681 


Potential 
Energy. 


I,  Sao 


1,940 
2,138 


2,304 
2,343 

2,324 
2,401 

2,762 
2,500 
2,757 
3;OS3 
3,085 
3,194 
3,569 
4,i'7 
4,'9S 

4,641 

5,692 
2,798 
3,093 

4,652 
3.675 
3,436 
4i72f 


ACTUAL  DIETARIES 
ACTUAL  DIETARIES— continued. 


33 


Classes. 


29. 
3°- 

3"« 
31^. 

32a 
32(5. 
33'« 

34- 
35- 
36- 
37- 

38. 
39- 


French  Canadians,  working  people,  in  Canada 

French    Canadians,    faciery  operatives,    me- 
chanics, etc.,  in  Masisachusetts 

Other    factory    operatives,    mechanics,   etc., 
Massachusetts  . . 

Glass-blowers,  East  Cambridge,  Mass. 

Factory  operatives,  dressmakers,  clerks,  etc., 
boarding-house 

\  Well-to-do  private  family,  (  food  purchased 
( food  eaten 


(  food  purchased 
(  food  eaten 
J  food  purchased 
I  food  eaten 


)      Connecticut 
College   students   from 
Northern  and   East- 
ern States  ;  boarding- 
club,  2  dietaries  of  the 
same  club 
College  football  team,  food  eaten 
Machinist,  Boston,  Mass. 
Brick-makers,  Middletown,  Conn. 
Teamsters,   marble-workers,  etc.,    with   hard 

work;  Boston,  Mass. 
Brick-makers,  Cambridge,  Mass. 
U.S.  Army  ration 
U.S.  Navy  ration 

Average  of  53  American  studies  for  different 
classes      ..         ..         ..         ..         .. 

Average  diet  of  labourer's  family  in  Edin- 
burgh 
Chinese  dentist's  family 
Japanese  professional  man 
Professional    men    in   America   (average    of 

14  studies) 
Malays  (professional  men) 
Europeans  in  Java  (professional  men) 
University  boat  crews  (average  of  7  studies) 
Average    of   4    women    students'    clubs   in 

America 
Average    of    16     men    students'    clubs    in 

America 
Average  of  21  dietary  studies  amongst  the 

labouring  classes  in  Dublin  . . 
Averac;e  dietary  of  5  halls  of  residence  for 

students  in  Edinburgh 
Dietary  of  a  studerits'  club  in  Finland' 


Nutritive  Constituents. 


Protein. 


Grms. 
109 

118 

127 
95 

114 
129 
12S 

161 

138 

"5 
104 

i8i 
182 
222 


120 
J43 


Fats. 


177 

204 
184 
163 
136 

292 
254 
263 

363 
365 
161 
184 


Carbo- 
hydrates. 


Grms. 
527 
549 
531 


522 

467 
466 

680 
622 
460 
421 

557 
617 
758 

826 

1,150 

454 

520 


Total. 


103 

138 

436 

107-7 

63 

88-4 
113 
3 

479  "4 

289 

481 

104 

t25 

423 

73 
100 

30 
84 

472 
264 

155 

177 

440 

lOI 

139 

414 

105 

147 

46s 

98-5 

927 

453'6 

«43 
157 

138 
191 

5" 

380 

Grms. 
745 
871 

844 
708 

786 
779 
771 

1,04s 

944 
738 
661 

1,030 
i>053 
1.243 

1.443 
1,695 

735 

847 

677 
675'S 


Potential 
Energy. 


Caloriet. 
3,622 

4.632 

4,428 
3.590 

4,002 
4,146 
4,082 

5.345 
4.827 
3.874 
3.417 
5.742 
5,638 
6,464 

7,804 
8,848 
3,85' 
4,998 


3.328 
2,705 
2,258 

3,325 
2,512 
2,470 
4,085 

3,40s 


3,979 
3.984 


On  examining  the  table,  it  will  be  observed  that,  on  the  whole,  the 
results  conform  very  closely  to  the  ideal  standard  already  laid  down. 
Here  and  there,  however,  one  meets  with  divergences.  Thus,  the 
diet  (No.  i)  of  the  sewing-girl  in  London  (which  was  investigated  by 
Playfair)  must  be  regarded  as  insufficient  for  the  needs  of  health, 
while  that  of  the  well-to-do  family  in  Connecticut  (No.  31)  is  need- 
lessly liberal.  Taking  the  results  as  a  whole,  however,  one  is 
astonished  at  the  closeness  with  which  the  actual  corresponds  to 
the  ideal. 

*  Sundstrom,  Skand.  Archiv }.  Physiol.,  1907,  xix.  78. 


34  FOOD  AND  DIETETICS 

Application  of  these  Standards. 

It  must  be  clearly  realized  that  such  standard  dietaries  as  those 
we  have  been  considering  have  only  a  limited  range  of  usefulness. 
They  cannot  be  rigidly  applied  in  any  particular  case,  for  they  have 
only  been  drawn  up  to  meet  the  needs  of  typical  individuals  living 
under  known  conditions,  and  doing  a  moderate  amount  of  muscular 
work.  They  are  of  great  value,  however,  in  helping  us  to  draw  up 
rations  for  persons  who  have  no  free  choice  in  their  diet,  and  who 
are  living  under  fairly  uniform  conditions  {e.g.,  soldiers  and  the 
inmates  of  prisons,  workhouses,  etc.),  and  as  furnishing  us  with  a 
standard  by  which  to  gauge  the  probable  sufficiency  or  otherwise  of 
the  dietary  which  choice  or  necessity  has  imposed  upon  any  section 
of  the  community.  A  good  example  of  the  application  of  such  a 
standard  in  the  former  case  is  supplied  by  Dr.  J.  C.  Dunlop's 
investigations  into  prison  diets  in  Scotland.^  Illustrations  of  its  use 
in  estimating  the  value  of  the  diet  in  sections  of  the  community 
have  been  furnished  in  this  country  by  the  investigations  of  Noel 
Paton  and  others  into  the  diet  of  the  labouring  classes  in  Edinburgh, ^ 
those  of  Rowntree  into  that  of  the  poorer  sections  of  the  community 
in  York, 3  of  C.  D.  La  Touche  and  T.  T.  Stafford  in  the  case  of 
working-class  families  in  Dublin,  and  of  Miss  I.  D.  Cameron  into 
the  dietary  in  five  students*  halls  of  residence  in  Edinburgh.*  The 
results  of  these  investigations  will  be  referred  to  in  the  next  chapter. 

1  Report  to  the  Prison  Commissioners  for  Scotland.  London  :  P.  S.  King  and 
Son,  1899. 

2  '  A  Study  of  the  Diet  of  the  Labouring  Classes  in  Edinburgh.'  Edinburgh  : 
Otto  Schulze  and  Co. 

^  '  Poverty  :   A  Study  of  Town  Life.'     London  :    Macmillan  and  Co,     New 
edition,  1903. 
*  Proceedings  of  the  Royal  Society  of  Edinburgh,  1905-6,  xxvi.,  327. 


[  35   ] 


CHAPTER  III 

ON   THE   INFLUENCE   OF  VAEIOUS  CONDITIONS   UPON   THE 
AMOUNT  OF  FOOD  REQUIRED 

I.   Work  and  Rest. 

Of  all  the  factors  which  affect  the  amount  of  food  required,  work 
and  rest  are  by  far  the  most  potent.  So  much  is  this  the  case  that 
all  other  influences  are  negligible  in  comparison.  We  shall  consider 
the  influence  of  muscular  work  first.  We  may  accept  the  estimate 
of  100,000  kilogramme-metres  (324  foot-tons)  as  representing  a 
moderate  amount  of  muscular  work  for  one  day,  and  the  heat 
equivalent  of  this  is  210  Calories.  Seeing,  however,  that  the  human 
body  can  only  transform  about  one-fifth  of  the  energy  supplied  to  it 
in  the  form  of  food  into  work,  the  remainder  being  dissipated  as 
heat,  it  Avill  be  evident  that  more  than  1,000  Calories  of  energy  must 
be  supplied  as  food  in  order  to  enable  this  amount  of  work  to  be 
done.  Seeing,  further,  that  the  mere  maintenance  of  the  body 
requires  a  daily  intake  of  about  2,000  Calories  of  energy,  one  arrives 
at  the  conclusion  that  the  total  daily  energy  value  of  the  diet  for  a 
man  doing  a  moderate  amount  of  muscular  work  must  be  somewhere 
about  3,000  Calories. 

It  should  be  observed,  however,  that  the  exact  expenditure  of 
energy  required  for  the  performance  of  any  particular  piece  of  work 
depends  to  a  large  degree  upon  the  practice  and  training  of  the 
worker.  An  untrained  worker  is  more  extravagant  in  his  output  of 
energy  for  any  given  task  than  one  who  is  more  habituated  to  its 
performance,  and  much  of  the  value  of  training  depends  upon  the 
acquirement  of  the  power  of  doing  work  with  a  minimum  waste  of 
effort,  and  of  employing  for  it  only  those  muscles  which  are  really 
necessary. 

The  following  are  the  estimates  arrived  at  by  Rubner  for  the 
intake  required  for  different  kinds  of  work : 


36  FOOD  AND  DIETETICS 

1.  Rest  (e.|'.,  clerk  at  a  desk)    ..         „         ., 

2.  Professional  work  (£.^.,  a  doctor)  .. 

3.  Moderate  muscular  work  (e.g.,  a  house-painter) 

4.  Severe  muscular  work  {e.g.,  a  shoemaker) 

5.  Hard  labour  (e.g.,  a  blacksmith  or  navvy) 


2,500  Calories. 
2,631 

3,121  „ 
3.659  „ 
5.213        II 


A  reference  to  the  table  on  p.  31  will  show  that  even  larger 
quantities  than  the  last  of  these  are  sometimes  actually  consumed. 
Brickmakers,  for  example,  whose  occupation  is  one  of  the  most 
laborious  known,  were  found  to  take  in  food  to  the  value  of  more 
than  8,000  Calories  daily.  On  the  other  hand,  a  German  doctor 
consumed  less  than  3,000  Calories,  although  medicine  is  by  no  means 
a  sedentary  occupation,  while  the  consumption  of  a  Trappist  monk, 
living  in  the  retirement  of  the  cloister,  amounted  to  hardly  more 
than  2,000  Calories  per  day. 

Atwater's  American  standards  are  as  follows : 

Calories. 
Man  without  muscular  work  ••         ,,         ••         ..     2,700 

Man  with  light  muscular  work        ..         ,,         ..         ..     3,000 
Man  with  moderate  muscular  work  ••         ..         ..     3,500 

Man  with  severe  muscular  work    .•         ••         ..         ..     4,500 

The  standards  determined  by  Lyon  Playfair  as  long  ago  as  1865 
work  out  in  Calories  thus  :* 

Caloriis. 

Subsistence  diet         ..         .•         ..         ..         «.         ..  2,102 

Soldier  (^peace),  light  work  . .  ..         ..         ..  ..  3,029 

Soldier  (war),  moderate  work  ..         ..         ..         ..  3,146 

Royal  Engineers,  moderate  work 3, 818 

Labourers,  moderate  work    ..  ..         ..  ..  ..  3,611 

Average  for  moderate  work  . .         ».         • 3,525 

Admitting  that  with  an  increase  of  work  there  must  be  a  corre- 
sponding increase  in  the  total  amount  of  food  consumed,  the  further 
question  arises.  In  what  form  is  the  extra  energy  to  be  supplied  ? 
Should  it  be  met  by  an  increase  of  protein,  of  carbohydrate,  or  of 
fat,  or  should  all  be  increased  alike  ?  In  attempting  to  reply  to  this 
question,  we  enter  the  arena  of  much  physiological  controversy, 

*  See  'A  Study  of  the  Diet  of  the  Labouring  Classes  in  Edinburgh,'  by 
Noel  Paton,  J.  C.  Dunlop,  and  Elsie  M.  Inglis,  p.  5.  Edinburgh:  Otto 
Schulze,  1901. 


DIET  STANDARDS  FOR  HARD  WORK  37 

for,  stated  in  another  way,  the  problem  to  be  solved  is  this :  from 
what  source  do  muscles  derive  the  energy  which  enables  them  to 
do  work  ? 

In  the  earlier  part  of  the  last  century  most  physiologists 
believed  with  Liebig  that  nitrogenous  matter — in  short,  protein- 
was  the  muscle  food  par  excellence.  It  was  supposed  that  if  much 
work  had  to  be  done,  much  protein  must  be  supplied.  Soon  there 
arose  another  school,  who  contended,  and  backed  their  contention 
by  incontrovertible  experimental  evidence,  that,  when  hard  muscular 
work  is  done,  it  is  the  carbonaceous,  and  not  the  nitrogenous, 
constituents  of  the  body  which  suffer  increased  waste.  Of  the 
carbon-containing  constituents  of  the  food,  the  carbohydrates  soon 
came  to  be  regarded  as  the  most  valuable  sources  of  muscle 
energy,  a  view  in  favour  of  which  evidence  is  still  accumulating 
(see  p.  282),  But,  as  often  happens  with  the  progress  of  knowledge, 
our  views  on  this  subject  have  tended  to  swing  back  a  little,  and 
now  physiological  opinion  seems  to  have  crystallized  in  a  middle 
position,  in  which  it  may  be  said  that  a  muscle  is  able  to  utilize  any 
of  the  nutritive  constituents  of  food  for  its  work,  but  that,  as  long 
as  there  is  a  sufficiency  of  carbon-compounds  present,  these  are  pre- 
ferred to  the  nitrogenous/ 

Direct  observation  of  the  diets  actually  selected  by  men  engaged 
in  severe  toil  confirms  this  conclusion.  Diets  Nos.  16,  17,  33  and  34, 
in  the  table  (pp.  32,  33)  may  be  taken  as  examples.  It  will  be  observed 
that  in  these  all  the  nutritive  constituents  are  increased,  but  that 
some  have  elected  to  consume  the  excess  of  carbon  in  the  form  of 
fat,  others  chiefly  as  carbohydrate.  Both  meet  the  requirements 
equally  well,  but  carbohydrate  has  the  advantage  of  being  a  cheaper 
source  of  supply.  On  the  other  hand,  fat  is  less  bulky,  and  those 
who  can  afford  it  do  well  to  take  in  a  large  share  of  the  increased 
energy  they  require  in  that  form. 

An  increase  of  protein  in  the  diet  of  toil  is  necessary,  not  so  much 
to  provide  additional  energy  as  to  make  good  the  increased  wear 
and  tear  of  muscle  substance  which  the  performance  of  hard  work 
necessarily  involves,  as  well  as,  in  some  cases  at  least,  to  enable  the 
muscle  to  add  to  its  bulk. 

From  an  examination  of  such  diets,  the  following  standards  have 

*  For  experimental  evidence  leading  to  the  same  conclusion  see  Frentzel 
('  Ergographic  Experiments  upon  the  Restorative  Effects  of  Various  Nutritive 
Substances  in  Muscular  Fatigue'),  Archiv  fur  Anat  una  Physiol,,  Sup.  Bd.,  1899, 
P-  141. 


38  FOOD  AND  DIETETICS 

been  constructed,  which  may  serve  as  guides  to  the  amount  of 
each  nutritive  constituent  required  during  the  performance  of  hard 
labour : 


Authority. 

Protein. 

Fat. 

Carbohydrate. 

Calories, 

Voit      . . 

145 

100 

450 

3.370 

Rubner 

165 

70 

565 

3.644 

Playfair 

185 

71 

568 

3.750 

Atwater 

150 

150 

500 

4,060 

The  amount  of  protein  allowed  is  in  each  case  considerably  above 
the  average  standard  for  moderate  work  (120  grammes).  The  sum 
of  carbohydrate  and  fat  is  also  raised,  but  in  some  cases  the  main 
increase  has  fallen  upon  the  former,  in  others  upon  the  latter.  The 
subject  under  discussion  has  important  bearings  upon  the  diet  of 
training. 

Training  may  be  described  as  a  process  by  which  the  body  is 
fitted  to  perform  severe  muscular  feats. ^  The  chief  means  by  which 
one  seeks  to  accomplish  this  object  are  the  reduction  of  weight  by  the 
removal  of  superfluous  water  and  fat,  and  the  improvement  of  the 
tone  of  the  muscles  and  heart,  which  produces  endurance  and  long 
*  wind.'  The  first  of  these  objects  is  attained  by  reducing  the 
amount  of  fat  in  the  diet,  and  by  restricting  the  amount  of  fluid  to 
that  which  is  required  to  satisfy  actual  thirst.  That  the  reduction 
of  fluid  in  the  body  is  physiologically  justifiable  is  evident  from  the 
fact  that  a  watery  condition  of  the  muscles  and  blood  does  not 
conduce  to  an  energetic  condition  of  body  (see  also  p.  180).  On  the 
other  hand,  the  opposite  extreme  should  be  avoided,  for  a  too  viscid 
condition  of  the  blood  is  equally  unfavourable. 

No  dietetic  means  have  been  consciously  used  to  accomplish  the 
second  object — the  improvement  of  the  tone  of  the  muscles  and 
heart.  Experience,  however,  seems  to  show  that  the  results  of 
these — i.e.,  a  gain  in  power  of  endurance  and  wind — are  attained  by 
increasing  the  amount  of  protein  consumed,  and  in  practice  this 
takes  the  form  of  eating  large  quantities  of  meat.  It  may  be  asked 
if  this  increased  consumption  of  protein  can  be  defended  on  scientific 
grounds.  To  some  extent,  yes.  Protein  is  the  nutritive  ingredient 
least  likely  to  be  converted  into  fat,  and  is  also,  on  the  whole,  the 
most  easily  digested,  and  any  disturbance  of  digestion  seems  to 
militate  greatly  against  the  accomplishment  of  the  objects  of  training. 
Moreover,  the   hard   exercise  which   is   practised   during   training 

1  See  also  on  this  subject  Clement  Duke's  '  School  Diet,'  chapter  xi.,  '  The  Diet 
in  Training  for  School  Games. ' 


DIET  STANDARDS  FOR  HARD  WORK  39 

involves  a  great  deal  of  wear  and  tear  in  the  muscles,  and 
sometimes  also  an  increase  in  their  bulk,  and  both  of  these 
results  must  be  provided  for  by  an  increased  consumption  of  pro- 
tein. 

Further,  also,  in  sudden  and  short  muscular  feats,  such  as  those 
for  which  training  is  a  preparation,  whaJt  is  required  is  a  large 
output  of  energy  for  a  short  time.  Protein,  being  a  '  quick  fuel,'  is 
probably  better  adapted  to  secure  this  end  than  either  carbohydrate 
or  fat.i  In  recent  years  there  has  perhaps  been  a  tendency  to  lay 
less  stress  on  the  use  of  meat,  to  recognise  that  in  training,  as 
in  other  conditions,  the  same  diet  does  not  suit  all  persons  equally 
well,  and  to  recommend,  rather,  the  use  of  ordinary  foods,  taken  in 
increased  quantity,  and  with  the  avoidance  of  anything  likely  to 
produce  indigestion,  such  as  pastry  and  sweets.  This  is  probably  a 
move  in  the  right  direction  ;  but  one  would  like,  on  scientific  grounds, 
to  see  sugar  more  largely  tried. 

The  tendency  would  still  seem  to  be  to  eat  too  much  and  at  too 
long  intervals.  '  He  that  striveth  for  the  mastery,'  says  the  Apostle, 
'  is  temperate  in  all  things.'  And  this  applies  to  diet  as  well  as  to 
everything  else. 

The  chief  scientific  studies  of  the  dietaries  of  persons  engaged  in 
athletic  exercises  have  been  made  in  America.^ 

One  of  these  concerns  the  diet  of  Sandow,  '  the  strong  man,' 
and  is  on  that  account  of  some  special  interest.  We  read  that : 
'  Mr.  Sandow  does  not  follow  any  prescribed  diet,  but  eats  whatever 
he  desires,  always  being  careful  to  eat  less  than  he  craves  rather 
than  more.  He  eats  very  slowly.  .  .  .  Sometimes  he  takes  a  cup 
of  weak  tea  and  a  little  bread  in  the  morning,  but  usually  his  first 
meal  is  eaten  about  noon.  He  eats  again  about  six  o'clock,  and 
again  about  midnight,  after  his  exhibition  of  feats  of  strength  is 
over.  He  smokes  a  good  deal,  and  drinks  beer  and  other  alcoholic 
beverages.' 

'  The  total  amount  of  food  consumed,'  says  the  writer,  •'  is  rather 
more  than  the  average,  though  in  his  own  opinion  Mr.  Sandow  is 
not  a  large  eater.  This  is  in  accord  with  the  general  conclusion 
reached  in  many  investigations  made  with  labouring  men,  that 
severe  muscular  exercise  requires  an  abundant  diet.' 

1  It  is  also  beginning  to  be  believed  by  some  physiologists  that  work  which 
causes  a  high  degree  of  nervous  and  mental  strain  demands  for  its  performance  a 
larger  supply  of  protein  than  the  same  amount  of  labour  carried  out  in  a  more 
leisurely  manner  and  under  less  pressure. 

2  Langworthy  and  Beal,  Storr's  Agricultural  Experiment  Station,  Ninth  Annual 
Report,  part  ii.,  1896. 


40 


FOOD  AND  DIETETICS 


The  following  table  represents,  approximately,  Sandow's  diet  for 
one  day  : 


Food  Consumed. 
iQuantities  in  Ounces.'^ 

Nutrients. 

.2>, 

^J 

DMe. 

I 

ex, 

i 

63 

•£  « 

■S'5 

a" 

yan.  XO. 
Dinner    - 

Supper 
yan.  II. 

Break- 
fast 2 

2  oysters,  lo  soup,  i  celery,  3  fish, 
I  potatoes,  2  oyster  plant,  i  green 
peas,  I  tomatoes,  2  bread,  2  roast 
beef,  2|  chicken,  4  ice  cream, 
3     orange     sherbet,     ^    cakes, 

1  butter,  II  wine  (Burgundy)  .. 

8  roast  beef,  7^  rye  bread,  3^  Cam- 
embert  cheese,  2  water  biscuit, 
3i  cakes,  4-4  lb.  beer*   . . 

9  vegetable  soup,  2  potatoes,  3  veal 

(breaded   chop),   ^  green   peas, 

2  roast  beef,  4^  bread  pudding, 
J  cakes,  14  beer  . .         . , 

Total  in  pounds      .. 
Total  in  grammes  .. 

lb. 

•26 
•II 

a. 

•14 
M 

•05 

a. 

•34 

•61 

•16 

Calorie*. 

i: 

244 

•33 
151 

i-ii 

502 

4.462 

3*4 

The  average  composition  of  the  diet  consumed  by  some  University 
boat  crews  in  America  was  as  follows  :^ 


Protein         . . 
Fat    .. 
Carbohydrates 


155  grammes 

177 

440 


I- 


=  4,085  Calories. 


Two   studies   of  the   diet  of  college  football  teams  yielded  the 
following  results  :  * 

No.  I. 
Protein  ..   181  grms."]   _, 

Fat      ..         ..   292      „      [calories 
Carbohydrates  557      „     J  '-aiones. 

An  investigation  of  the  diets  of  two  Scandinavian  professional 
athletes  resulted  as  follows :' 


No.  2. 

Protein  . .  270  grms. 

Fat      ..         ..  416     ,, 
Carbohydrates  710      ,, 


=  7,885 
Calories. 


No.  I. 
Protein  ..  217  grms/|   _,„„ 

^^*      ••         ••   259    „       hclloSs 
Carbohydrates  431     „      J  ^aiones. 


Protein 

Fat      . .         . .  204 

Carbohydrates  392 


No.  2. 

182  grms.  1^,^^^ 

j  Calories. 

The  most  striking  points  about  the  above  dietaries  of  athletes  are 
(i)  the  large  amount  of  total  energy  which  they  contain,  and  (2)  their 

*  Sandow  sat  a  long  time  with  friends  after  supper,  and  consumed  a  large  part 
of  the  beer  during  this  time. 

2  This  was  the  regular  meal  served  at  the  hotel. 

3  'Dietary  Studies  of  University  Boat  Crews,'  Bull.  No.   75,  United  States 
Department  of  Agriculture.  Office  of  Experiment  Stations,  1900,  p.  66. 

*  Ibid.  6  Lavonius,  Skand.  Archiv  f.  Physiol.,  1905,  Bd.  xvii.,  196. 


DIET  STANDARDS  FOR  HARD  WORK  41 

richness  in  protein,  the  former  being  about  15  per  cent.,  and  the 
latter  25  per  cent.,  above  the  standard  for  moderate  muscular  work. 
It  seems  reasonable  to  suppose  that  these  peculiarities  are  a  response 
to  the  physiological  demands  which  athletic  contests  make  upon  the 
body,  and  that  the  diet  of  training  should  be  one  yielding  a  large 
amount  of  energy  and  containing  a  relatively  high  proportion  of 
protein. 

Mental  work  influences  the  amount  and  nature  of  the  food 
required  in  a  very  different  way  from  muscular  labour.  The  first 
thing  which  it  is  important  to  realize  clearly  is  that  brain  work 
does  not  appreciably  increase  bodily  waste.  On  this  point  all 
exact  experiments  agree.  One  of  the  most  careful  of  these  is  re- 
corded by  Atwater.^  A  man  was  confined  in  a  respiration  calori- 
meter for  a  number  of  days,  and  on  certain  of  them  he  engaged  in 
the  severe  mental  work  of  reading  a  German  treatise  on  physics. 
The  subject  of  the  experiment,  it  may  be  added,  was  an  intelligent 
person,  who  fully  understood  the  nature  of  the  experiment,  and  did 
not  shirk  mental  application.  It  was  found  that  on  the  working 
days  bodily  waste  was  no  greater  than  during  rest. 

The  next  point  to  get  hold  of  is  that  there  is  no  special  brain  food. 
Biichner  gave  utterance  to  the  dictum,  '  Without  phosphorus  there 
is  no  thought.'  This  is  only  true  in  the  sense  that  the  brain  contains 
phosphorus,  and  without  the  brain,  thought,  as  we  know  it,  is 
unthinkable.  But  it  has  never  been  shown  that  an  increased  supply 
of  phosphorus  in  the  food  is  specially  favourable  to  mental  effort, 
nor,  indeed,  has  that  been  proved  for  any  other  food.2  jt  requires, 
of  course,  no  special  demonstration  that  an  ill-nourished  brain  is  not 
one  from  which  good  work  can  be  expected  :  for  the  brain,  like  every 
other  organ,  demands  for  its  work  an  abundant  supply  of  healthy 
blood,  and  there  is,  perhaps,  no  part  of  the  body  which  is  more 
sensitive  to  any  impoverishment  of  that  fluid.  On  the  other  hand,  any 
oversupply  of  food  must  be  equally  unfavourable  to  mental  work.  A 
large  amount  of  food  implies  a  large  amount  of  work  on  the  part  of 

^  United  States  Department  of  Agriculture,  Bull.  44,  1897.  For  later  experi- 
ments, which  also  tended  to  show  that  mental  effort  has  no  positive  influence  on 
metabolism,  see  United  States  Department  of  Agriculture,  Office  of  Experiment 
Stations,  Bull.  208,  1909. 

2  Mairet  and  Florence  (abstract  in  Brit.  Med.  Journ.,  1907,  ii.  539)  have 
shown  by  experiment  that  during  intellectual  labour  the  amounts  of  nitrogen  and 
phosphoric  acid  absorbed  from  the  alimentary  canal  are  diminished,  as  compared 
with  the  period  of  repose,  either  following  or  preceding  the  spell  of  mental  work, 
and  that  appreciably  more  phosphorus  is  eliminated  during  mental  work  than 
is  absorbed  in  the  same  time.  These  results,  however,  might  be  explained  by  an 
adverse  influence  exerted  by  hard  mental  labour  on  the  processes  of  digestion 
and  absorption. 


42  FOOD  AND  DIETETICS 

the  digestive  organs,  and  that,  in  its  turn,  implies  a  large  expenditure 
of  nervous  energy  and  blood.  But  if  more  blood  is  required  in  the 
abdomen,  there  must  be  less  left  for  the  brain,  and  the  activity 
of  the  latter  declines,  as  is  evidenced  by  the  feeling  of  lethargy 
which  is  familiar  to  everyone  after  a  large  meal.  It  comes,  then,  to 
this,  that  the  digestibility  of  a  food  is  of  far  greater  concern  to  a  brain  zvorher 
than  its  chemical  composition.  Small  and  rather  frequent  meals  of 
easily-digested  food  is  the  ideal  to  aim  at.  The  necessity  for  this 
is  the  more  apparent  when  one  remembers  that  brain  work  is 
usually  also  sedentary  work.  Compared  with  the  diet  of  muscular 
labour,  therefore,  the  diet  for  mental  work  should  be  small.  The 
reduction  should  probably  affect  carbohydrates  and  fats  more  than 
protein,  for  it  is  the  two  former,  as  we  have  seen,  which  tend  to  be 
specially  made  use  of  as  muscle  foods.  The  protein  consumed 
should  be  derived  to  a  large  extent  from  animal  foods,  for  these  are 
its  most  compact  and  digestible  source.  Hence  it  is  that  it  is  far 
easier  for  a  man  who  is  performing  bodily  labour  to  be  a  vegetarian, 
than  for  one  who  is  engaged  in  mental  work.  Whether  an  abundant 
supply  of  protein  has,  per  se,  an  actually  stimulating  influence  on  the 
brain  must  be  left  undecided,  though  such  a  view  is  not  without  its 
supporters. 1 

fi.est,  as  might  be  expected,  influences  the  amount  of  food  required 
in  a  precisely  opposite  direction  to  muscular  work.  Much  less  food 
is  required  in  the  former  condition  than  in  the  latter.  The  reduction, 
however,  should  not  affect  all  the  nutritive  constituents  equally. 
Even  when  the  body  is  in  complete  repose  there  is  still  wear  and 
tear  of  its  substance  going  on.  Such  waste,  indeed,  is  inevitable, 
for  it  is  an  invariable  accompaniment  of  even  passive  life,  and  one 
finds  that  during  rest  the  excretion  of  carbonic  acid  is  much  more 
profoundly  influenced  than  that  of  nitrogen.  The  practical  result  is 
that  in  the  diet  of  repose  the  carbohydrates  and  fats  should  be 
relatively  more  restricted  than  the  proteins.  The  energy  value  of 
such  a  diet  may  even  fall  to  2,000  Calories  or  less,  and  yet  prove 
sufficient  for  the  bodily  needs.  This  is  a  fact  of  great  value  in 
therapeutics.  It  explains  why  it  is  that  one  has  so  much  less 
difficulty  in  fattening  a  patient  when  at  rest  in  bed  than  when  up 
and  about ;  for  the  former  condition  the  demand  both  for  heat  and 
energy  is  enormously  lessened.  Sleep  intensifies  the  benefits  of 
rest  by  insuring  more  absolute  relaxation  of  the  muscles,  and  also 
seems  in  itself  to  lessen  somewhat  the  waste  of  fat.  A  German 
writer  (Lobisch)  goes  so  far  as  to  assert  that  an  extra  hour's  sleep  at 
night  is  equivalent  to  a  saving  of  2^  pounds  of  fat  in  a  year. 

•  See  Roberts,  '  Digestion  and  Diet, '  p.  log. 


INFLUENCE  OF  WEIGHT  AND  BUILD  43 


2.  Influence  op  Weight  and  Build. 

The  heavier  the  body — i.e.,  the  greater  the  number  of  cells  which 
it  contains — the  greater  is  the  amount  of  food  required  for  its  main- 
tenance. This  is  true  as  a  general  statement,  but  in  practice  the 
kind  of  cell  which  is  increased  must  also  be  considered.  The  nutri- 
tive requirements  of  a  pound  of  bone,  a  pound  of  fat,  and  a  pound  of 
muscle  are  very  different.  Fat  and  bone  are,  so  to  speak,  dead 
tissues.  Their  vital  activity  is  but  slight,  their  daily  wear  and  tear 
small.  Muscle,  on  the  other  hand,  is  a  highly  active  tissue  con- 
stantly breaking  down,  and  requiring  not  merely  much  protein  to 
repair  its  waste,  but  making  frequent  demands  on  the  carbonaceous 
foods  to  provide  it  with  a  supply  of  energy.^  Thus  it  is  that  a  man 
whose  weight  is  mainly  due  to  muscle  will  require  relatively  more, 
and  especially  more  nitrogenous,  food  than  one  who  owes  his  weight 
to  the  size  of  his  bones  or  to  a  substantial  covering  of  fat.  Taking 
the  average  man,  however,  the  following  estimate  of  the  number  of 
Calories  required  for  every  kilo  of  body-weight  in  different  circum- 
stances will  be  found  to  hold  good : 

Calories  per  Kilo. 
(2 -2  pounds). 

In  bed . .         ..     30  to  34 

Up,  but  doing  no  work  ..  ..  ..     34  to  40 

At  moderate  muscular  work  . .  . .  . .     40  to  45 

At  hard  muscular  work  . .  . .  . .     45  to  60 

On  the  other  hand,  and  for  the  reason  given  above,  26  to 
36  Calories  per  kilo  will  probably  suffice  for  a  man  who  is  very 
stout. 

Rubner^  gives  the  following  estimates  of  the  amount  of  energy  and 


1  Dr.  Smith  {Lancet,  May  21,  1864)  gives  the  amount  of  fat  consumed  under 
different  conditions  as  follows  : 

One  hour  of  lying  asleep  consumes      ..         ..         ..  0-31  ounce. 

lying  awake         ,,  ..  ..  ..  046      „ 

standing  ,,  . .  . .  . .  055      „ 

walking  at  two  miles  per  hour  consumes  i  •  i    ounces. 

,,  three         ,,  ,,  ,,  i-6        ,, 

work  on  a  treadmill  consumes  275      ,, 

Ranke  compared  the  output  of  two  men  of  equal  weight,  one  fat,  the  other 
muscular,  and  both  fasting,  with  the  following  results  : 

Musctilar  Man.     Fat  Man. 
Protein        ....  78  50 

Fat  ..         .,         ..  215  204 

2  Leyden's  '  Handbuch  der  Ernabrungstherapie  und  Diatetik,'  2nd  ed.,  vol.  i., 
p.  153.  1903- 


44 


FOOD  AND  DIETETICS 


protein  required  by  persons  of  different  weight  in  the  same  circum- 
stances : 


Light  Work 

Moderate  Work 

Weight. 
St.    lb. 

Calories. 

Grammes 

Protein. 

Wtight. 
St.    lb. 

Calories. 

Grammes 
Protein. 

II     6 

2,864 

134 

II     6 

3,372       .. 

128 

10      o 

2,631 

123 

10    0 

3,094       •• 

118 

9     8 

..       2,368 

III 

9    8 

3,792       .. 

106 

7    2 

.„       2,102 

90 

7     2 

2,472       .. 

96 

5  lo 

1,810 

84 

5  10 

2,129       .. 

81 

The  build  or  shape  of  the  body  is  of  even  greater  importance  in 
this  connection  than  its  actual  weight.  Further,  we  may  say  that 
the  question  of  build  and  shape,  as  far  as  the  amount  of  food  required 
is  concerned,  resolves  itself  into  a  question  of  surface.  The  larger 
the  surface  of  the  body  relative  to  its  bulk,  the  greater  is  the  amount  of 
heat  lost  by  radiation,  and  the  greater  the  amount  of  food  required  to 
maintain  its  temperature.  A  reference  to  the  accompanying  diagram 
(Fig.  2)  will  make  this  clear.  Let  us  suppose  that  we  have  two 
bodies,  the  first  being  9  feet  high,  3  feet  broad,  and  i  foot  thick,  and 
the  second  measuring  3  feet  in  every  dimension.  Both  will  have  a 
cubic  content  of  27  feet,  but  the  first  will  have  a  surface  of  78  square 
feet,  the  second  of  only  54  square  feet ;  in  other  words,  the  surface 
exposed    is    almost    one -third 


greater  in  the  one  case  than 
in  the  other,  and  the  amount 
of  heat  lost  will  also  be  pro- 
portionately greater.  The  first 
of  these  figures  would  represent 
the  condition  of  a  tall,  thin 
man,  the  second  that  of  a  short, 
stout  man  ;  and  as  the  former 
must  lose  about  one-third  more 
heat  than  the  latter,  he  will 
obviously  require  about  one- 
third  more  fuel  in  the  form  of 
food  if  the  temperature  of  the 
two  is  to  remain  equal.  This  explains  the  apparent  paradox,  which 
is  otherwise  apt  to  prove  rather  puzzling,  that  a  thin  man  often  eats 
considerably  more  food  than  a  fat  man,  yet  the  former  remains 
lean  and  the  latter  becomes  more  and  more  stout.  The  former 
really  needs  more  food  simply  because  he  is  thin  ;  while  the  fatter 
a  man  becomes,  the  less  food  does  he  require,  for  with  every 
increase  in  bulk  there  is  a  corresponding  diminution  in  the  relative 
amount  of  surface  exposed.      When  one  estimates  the  amount  of 


t  reel        ■>. 

Fig.  2 — To  Illustrate  the  Influence 
OF  Shape  on  extent  of  Sorface. 


■  INFLUENCE  OF  BUILD  AND  SHAPE  45 

Calories  required  from  the  point  of  view  of  surface  rather  than  of 
mass  (body-weight),  it  is  remarkable  how  uniform  the  requirement 
is  for  all  persons  living  under  the  same  external  conditions.  The 
extent  of  body-surface  in  an  average  man  is  about  2i|^  square  feet, 
and  for  every  io|  square  feet  about  1,500  Calories  must  be  supplied 
daily. 

3.  Influence  of  Age  and  Sex. 

It  seems  to  be  a  general  principle  in  biology,  that  the  younger  the 
cell  the  greater  is  its  power  of  oxidizing  and  breaking  down  food, 
and  that  the  older  it  is  the  less  of  this  power  does  it  possess  ;  in 
other  words,  what  the  cells  of  the  body  gain  by  multiplication  they 
lose  in  individual  activity.  In  accordance  with  this  principle,  the 
assimilative  powers  of  a  child  are  greater  than  those  of  an  adult,  and 
those  of  the  latter  greater  than  those  of  an  old  man.  The  child,  there- 
fore, relatively  to  its  weight,  will  require  the  greater  amount  of  food. 

Two  other  considerations  emphasize  this  necessity.  Like  all 
small  animals,  a  child  has  a  large  surface  in  proportion  to  its  bulk, 
and  that  means,  as  we  have  just  seen,  a  relatively  great  heat  loss. 
Further,  a  child  is  a  growing  animal ;  it  has  not  merely  to  keep  its 
tissues  in  repair,  but  has  to  go  on  adding  to  them,  and  that  necessi- 
tates a  relatively  abundant  supply  of  building  material.^ 

The  practical  results  of  these  considerations  will  be  more  fully 
dealt  with  in  another  chapter  (Chapter  XXIV.),  but  they  have  led 
to  the  following  calculations  regarding  the  total  amount  of  food 
required  at  different  ages  as  compared  with  the  needs  of  a  fully- 
grown  man.2 

RELATrvE  Values  for  Food  Requirements  of  Persons  of  Different  Age 


AND    Occupation,    as    compared 

WITH    A    Man 

IN 

Full 

Vigour    at 

Moderate  Work. 

Man,  period  of  full  vigour: 

Boy,  15  to  16 

years 

old      . 

..     go 

At  moderate  work     . . 

100 

,,     13  to  14 

.     80 

At  hard  work  . . 

120 

,,     12  years 

old" 

. .     70 

Sedentary  occupation 

80 

,,     10  to  11 

years 

old      '. 

.     60 

Woman,  period  of  full  vigour 

Girl,  15  to  16 

.     80 

At  moderate  work     . . 

80 

,,     13  to  14 

•     70 

At  hard  work  . . 

100 

,,     10  to  12 

.     60 

Sedentary  occupation 

70 

Child,  6  to  9 

•     50 

Man  or  woman : 

„       2  to  5 

.     40 

Old  age 

90 

„      under  a 

•     30 

Extreme  old  age 

70-80 

^  It  must  be  remembered  that  during  the  period  of  active  growth  only  a  small 
fraction  of  the  increased  amount  of  food  taken  in  is  actually  stored  up  in  the 
body,  the  rest  being  broken  down,  and  increasing  thereby  the  general  metabolism. 
For  a  full  discussion  of  this  point  see  Rubner's  '  Beitrage  zur  Ernahrung  im 
Knabenalter  '  (Berlin  :   Hirschwald,  1902). 

*  Langworthy,  '  Year-book  of  Department  of  Agriculture'  (U.S.A.),  1907. 


46  FOOD  AND  DIETETICS 

The  '  nutritive  ratio  '  {i.e.,  the  proportion  of  building  material  to 
energy-yielding  constituents)  in  the  diet  of  an  adult  should  be,  we 
have  seen  (p.  29),  as  i  :  5*3,  or  thereabouts.  In  the  diet  of  a  child 
the  ratio  should  be  approximately  as  i  :  4-3. 

The  dietetic  requirements  of  old  age  are  just  the  reverse  of  those 
of  childhood.  The  assimilative  power  of  the  cells  is  on  the  wane^ 
and  the  bodily  activities  are  restricted,  hence  less  food  is  required. 
The  danger  of  overfeeding  the  old  is  almost  as  great  as  that  of 
underfeeding  the  young  ;  an  excess  of  nourishment  chokes  instead 
of  feeding  the  flickering  flame  of  life.  Leanness  and  longevity,  it 
has  been  remarked,  go  together,  and  a  man  will  only  roll  all  the 
faster  down  the  hill  of  life  if  his  figure  be  rotund.  '  Discerne,'  says 
Bacon,  '  of  the  coming  on  of  yeares,  and  thinke  not  to  doe  the  same 
things  still,  for  Age  will  not  be  defied,'  and  one  cannot  with 
impunity  continue  to  *  do  the  same  things  '  in  matters  of  diet  any 
more  than  in  anything  else. 

Forster  made  some  exact  investigations  into  the  diet  of  healthy 
old  persons,  and  found  that  it  contained  the  following  amounts  of 
nutritive  constituents  : 

Protein.  Fat.      Carbohydrates.     Calories. 

Men       ..  ..         92  45  332  2,149 

Women..         ..80  49  266  1.875 

The  results  fully  bear  out  the  above  contentions. ^  In  the  following 
diagram  (Fig.  3)  the  amount  of  each  nutritive  constituent  required 
at  different  periods  of  life  is  represented.  While  the  figures  must 
not  be  regarded  as  in  any  sense  absolute,  they  serve  to  represent  in 
a  graphic  way  the  relative  requirements  of  different  ages. 

Luigi  Cornaro  is  one  of  the  most  eloquent  advocates  of  temperance 
in  old  age.  '  It  cannot  be  urged  too  often,'  he  writes,"  '  that  when  the 
Natural  Heat  begins  to  decay  'tis  necessary  for  the  preservation  of 
health  to  abate  the  quantity  of  what  one  eats  and  drinks  every  Day  ; 
Nature  requiring  but  very  little  for  the  Support  of  the  Life  of  Man, 
especially  that  of  an  Old  Man.'  He  tells  us  that  he  ate  only  12  ounces 
of  solid  food  daily,  consisting  chiefly  of  bread,  wine,  broths  and  eggs, 
veal,  mutton,  partridges,  chicken,  and  pigeons,  and  some  kinds  of 
fish,  such  as  pike,  for  'all, of  these  aliments,'  he  adds,  'are  proper 
for  old  men.'  His  system  was  certainly  justified  by  its  results,  for 
he  is  said  to  have  lived  to  be  a  hundred  years  old. 

1  Von  Limbeck,  '  Zur  Lehre  vom  Stoffwechsel  im  Greisenalter,  Zeits.  fiir 
Klin.  Med.,  1894,  xxvi.  437.  See  also  Sir  Henry  Thompson's  '  Diet  in  Relation 
to  Age  and  Activity '  for  a  practical  discussion  on  the  subject. 

-  For  further  studies  of  the  diet  in  old  age  see  United  States  Department  of 
Agriculture,  Ofhce  of  Experiment  Stations,  Bull.  223,  1910. 

•'  '  Sure  and  Certain  Methods  of  Attaining  a  Long  and  Healthful  Life,'  trans- 
lated from  the  fourth  edition  ;  London.  1727,  p.  91. 


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48  FOOD  AND  DIETETICS 

Women  require  less  food  than  men,  for  their  bodies  are  not  only, 

as  a  rule,  of  less  weight,  but  are  relatively  richer  in  fat  and  poorer 

in  muscle  than  those  of  the  latter.     Further,  there  is  a  considerable 

amount  of  evidence  for  the  belief  that  the  cells  of  the  body  are  less 

able  to  carry  out  oxidation  changes  in  the  female  than  in  the  male  ; 

or,  in  physiological  language,  that  the  tendency  of  metabolism  is  in 

the  direction  of  a  preponderance  of  anabolism  in  the  one  case,  and 

of  katabolism  in  the  other.     Upon  this  supposition  a  whole  theory  of 

sex  differences  has  been  based.^    Whether  this  be  so  or  not,  there 

can  be  no  doubt  that  the  diet  of  the  female  should  be  less  in  amount 

than  that  of  the  male ;  and  it  has  been  estimated  that,  if  a  man 

consumes  lo  parts  of  food,  a  woman  under  similar  conditions  should 

require  only  8  parts.^    Expressed  in  terms  of  nutritive  constituents 

and  Calories,  the  diet  of  an  average  woman  doing  a  moderate  amount 

of  muscular  work  should  be  as  follows  : 

Protein.        Fat.        Carbohydrates.         Calories, 
90  40  400  2,381 

The  proportions  in  a  condition  of  rest  would  be : 

Protein       85 

Fat  . .         . .       • 40 

Carbohydrates      . .         . .         . .   320 

yielding  about  2,000  Calories  of  energy.  When  one  considers  the 
relative  requirements  of  the  two  sexes,  it  is  not  surprising  that  some 
of  the  most  aggravated  cases  of  obesity  should  be  met  with  in  women 
of  luxurious  life. 

4.  Influence  of  Climate  and  Season. 

The  influence  of  climate,  and  especially  of  a  warm  climate,  on  the 
amount  of  food  required  is  commonly  exaggerated.  It  seems  natural 
to  suppose  that,  if  the  surrounding  temperature  is  high,  the  amount 
of  heat  required  to  be  produced  in  the  body  will  be  less.  But  this 
is  to  lose  sight  of  the  fact  that  the  temperature  of  the  body  is  chiefly 
regulated  by  physical,  and  not  by  chemical,  means.  To  put  it  more 
plainly,  we  adjust  the  temperature  of  our  bodies  to  that  of  the 
surrounding  medium,  not  so  much  by  the  expensive  method  of 
increasing  or  diminishing  the  amount  of  heat  we  produce,  as  by  the 
simpler  expedient  of  regulating  the  amount  of  heat  lost. 

Heat  and  life,  as  has  been  already  pointed  out,  are  inseparable. 
We  cannot  help  producing  a  certain  amount  of  heat  if  we  are  to 
go  on  living  at  all.  Now,  thanks  to  the  fact  that  we  wear  clothes, 
our   bodies   live  in   an   atmosphere   of    about   90°    Fahr. — that   is 

*  Geddes  and  Thompson,  '  Evolution  of  Sex,'  1889. 

'  During  pregnancy,  L^wever,  the  diet  should  be  more  alundaat. 


INFLUENCE  OF  CLIMATE  AND  SEASON  49 

to  say,  in  what  is  practically  a  tropical  climate.  At  this  temperature 
the  amount  of  heat  produced  in  the  body  is  in  excess  of  its  require- 
ments, even  when  that  production  is  as  small  as  is  compatible  with 
the  full  activity  of  our  cells.  This  means  that,  even  in  a  temperature 
of  90°,  we  are  constantly  wasting  a  certain  amount  of  heat.  Suppose, 
now,  that  one  goes  into  the  tropical  regions.  As  the  external 
temperature  rises,  the  amount  of  heat  which  the  body  requires 
becomes  less  and  less ;  but  already  as  little  is  being  produced  as  is 
compatible  with  health,  so  that,  in  order  to  adjust  the  balance,  one 
must  not  try  to  diminish  the  production  by  eating  less  food,  but 
rather  to  increase  the  loss  by  wearing  thinner  clothes.  In  harmony 
with  this,  one  finds,  as  a  matter  of  fact,  that  the  consumption  of 
food  by  the  inhabitants  of  the  tropics  is  not  notably  less  than  that 
of  those  who  live  in  the  temperate  zone.^ 

Suppose,  on  the  other  hand,  that  one  moves  from  a  temperate  to 
a  colder  latitude.  The  body  will  now  require  more  heat  to  keep  its 
temperature  up  to  the  normal  level,  and  the  first  method  had  recourse 
to  in  order  to  meet  the  increased  demand  is  by  economizing  waste, 
or,  in  other  words,  by  diminishing  the  amount  of  heat  lost.  In 
practice,  this  is  accomplished  by  an  increase  of  clothing.  If  the 
external  temperature  falls  still  further,  however,  this  method  by 
itself  becomes  inadequate,  and  steps  must  be  taken  to  increase  heat 
production  ;  it  is  only  then  that  it  becomes  advisable  to  consume 
more  food. 

'  During  the  whole  of  our  march,'  says  Sir  John  Franklin,  in 
describing  his  journeyings  in  the  Arctic  regions,  '  we  experienced 
that  no  quantity  of  clothing  could  keep  us  warm  while  we  fasted,  but 
on  those  occasions  on  which  we  were  enabled  to  go  to  bed  with  full 
stomachs  we  passed  the  night  in  a  warm  and  comfortable  manner.' 
Translated  into  physiological  language,  this  means  that  the  demand 
for  heat  in  the  body  was  so  great  that  it  could  no  longer  be  met 
by  diminishing  loss,  but  that  the  deficit  had  to  be  made  up  by  an 
increase  of  heat  production — ».<?.,  by  a  greater  consumption  of  food. 

What  form  the  increased  consumption  of  food  takes  is,  com- 
paratively speaking,  of  little  moment.  All  that  is  really  necessary 
is  that  the  number  of  Calories  which  the  diet  is  capable  of  yielding 
should  be  considerably  raised.  As  a  matter  of  convenience,  how- 
ever, and  in  order  to  avoid  overfilling  the  stomach,  it  is  best  to  have 

1  It  would  seem,  however,  that  the  diet  of  tropical  dwellers  usually  contains 
relatively  less  protein  and  fat  and  more  carbohydrates,  especially  sugar,  than 
that  of  the  inhabitants  of  colder  regions.  See  a  paper  by  Harvey  W.  Wiley. 
Med.  News,  1904,  Ixxv.  943.  There  is  some  reason,  also,  to  believe  that  in 
hot  weather  and  in  warm  climates  the  digestive  capacity  is  not  so  great  as  in 
colder,  and  that  large  quauitities  of  food  are  consequently  not  so  well  borne. 

4 


50  FOOD  AND  DIETETICS 

recourse  to  fat  as  the  principal  source  of  the  extra  heat  required,  for 
fat  is  the  compactest  form  of  fuel  we  possess.  Carbohydrates  would 
serve  the  purpose  equally  well  as  far  as  the  cells  of  the  body  are 
concerned,  but  one  would  require  to  consume  more  than  twice  as 
much  of  them  as  of  fat  in  order  to  obtain  the  same  amount  of  heat. 
Besides,  in  very  cold  latitudes  carbohydrates  are  not  so  easily 
obtained  as  fat.  This  is  the  explanation  of  the  enormous  quantities 
of  blubber  which  the  Esquimaux  consumes,  as  much  as  20  pounds 
of  flesh  and  blubber,  we  are  credibly  informed,  being  eaten  in  the 
course  of  a  day  in  some  cases.  A  similar  adaptation  to  circum- 
stances on  the  part  of  Nature  is  seen  in  the  milk  of  the  walrus, 
Avhich  contains  40  per  cent,  of  fat,  thus  supplying  the  young  with  an 
abundant  and  compact  source  of  fuel,  and  enabling  them  to  maintain 
their  temperature  in  the  icy  waters  of  the  North. 

The  influence  of  season  on  the  amount  of  food  required  is  similar 
in  kind  to  the  influence  of  climate,  though  less  in  degree.  In  summer 
clothing  should  be  diminished  rather  than  food ;  in  winter  warmer 
clothing  should  be  worn,  but  the  amount  of  food,  and  especially  the 
proportion  of  fat  which  it  contains,  may  with  advantage  be  increased.^ 

Ranke  found ^  that  in  order  to  keep  his  body- weight  constant  he 
had  to  eat  as  much  food  in  summer  as  in  winter.  In  the  hot 
weather,  however,  the  inclination  to  eat  was  less,  and  if  he  followed 
his  appetite  the  fuel  value  of  his  diet  fell  by  as  much  as  400  Calories 
per  day.  If,  on  the  other  hand,  he  disregarded  his  inclinations  and 
ate  enough  to  maintain  his  body-weight,  his  health  suflFered,  a  result 
which  he  attributes  to  an  over-production  of  heat  in  the  body.  It 
would  seem  to  follow  from  this  that  a  slight  loss  of  weight  during 
the  summer  months  is  inevitable.  Hirschfeld,  criticising  these 
results, 8  is  inclined  to  attribute  the  bad  eff'ects  which  Ranke 
observed  to  follow  the  adoption  of  a  full  diet  in  hot  weather  to  an 
over-consumption  of  protein  rather  than  to  the  richness  of  the  diet 
as  a  whole.  It  certainly  seems  reasonable  to  avoid  in  warm  weather 
what  have  already  been  described  as  the  *  quick  fuels ' — i.e.,  those 
nutritive  constituents  from  which  a  large  amount  of  heat  can  be  pro- 
duced in  a  short  time,  especially  the  proteins.*     For  this  reason,  as 

1  It  has  been  estimated  that  800  Calories  more  of  energy  are  required  in  winter 
than  in  summer. 

2  '  Der  Nahrungsbedarf  im  Winter  und  Sommer  des  gemassigten  Klima  '  {Zeit. 
f.  Biologic,  1900,  xl.  28S). 

3  '  Ueber  Ernahrung  in  der  heissen  Jahreszeit  und  im  Warmen  Klima '  {Deut. 
Med.  Woch.,  1902,  xxviii.  674). 

*  Protein  is  not  only  in  itself  a  source  of  heat,  but  it  acts  as  a  stimulant  to 
metabolism,  thus  increasing  general  heat  production  in  the  body  as  well.  Hence, 
persons  who  live  on  minimal  amounts  of  protein  are  apt  to  be  very  sensitive  to  cold 


INFLUENCE  OF  IDIOSYNCRASY  51 

well  as  on  account  of  the  fact  that  they  are  relatively  rich  in  fat,  the 
animal  foods  should  be  more  sparingly  consumed  in  summer,  and  the 
proportion  of  vegetable  matters  in  the  diet  relatively  increased. 

5.   Influence   of    Personal   Peculiarity. 

There  is  a  widespread  impression  that  some  people  can  *  get  on' 
with  less  food  than  others,  even  although  they  are  living  under 
identical  external  conditions.  We  hear  it  said  of  one  man  that  he  is 
always  eating,  and  yet  remains  thin  and  languid  ;  of  another,  that 
he  lives  the  life  of  an  ascetic,  and  yet  grows  hearty  and  fat. 

To  a  large  extent  these  apparent  results  are  explicable  by  the 
diflferences  of  weight,  build,  and  shape  of  body,  which  we  have 
already  studied  ;  but  even  giving  such  considerations  their  full 
weight,  there  remains  some  room  for  the  belief  that  some  people 
really  do  make  better  use  of  their  food  than  others.  To  use  a 
popular  phrase,  they  '  put  it  into  a  better  skin.'  Scientific  evidence 
on  this  point  is  very  difficult  to  obtain.  Remembering,  however, 
that  the  utilization  of  food  is  a  function  of  living  protoplasm,  it  is  at 
least  conceivable  that  in  some  persons  the  activity  of  the  cells  is 
greater  than  in  others,  and  leads  to  a  more  rapid  breaking  down  of 
food  and  a  greater  waste  of  heat.*  It  has  been  clearly  proved  by 
scientific  experiment  that  a  man  who  is  skilled  through  long  practice 
in  doing  any  particular  piece  of  muscular  work  will  do  it  with  less 
expenditure  of  bodily  material,  as  expressed  in  the  excretion  of 
carbonic  acid  and  nitrogen,  than  a  novice.  In  other  words,  and  as 
far  as  that  particular  kind  of  work  is  concerned,  the  former  is  a  more 
economical  machine  than  the  latter,  and  there  is  really  no  very 
apparent  reason  why  there  should  not  be  degrees  of  such  economy 
in  the  performance  of  all  the  functions  essential  to  life. 

The  influence  of  the  nervous  system  in  regulating  tissue  waste  must 
also  be  borne  in  mind.  The  functions  of  nutrition  and  assimilation 
seem  in  some  mysterious  way  to  be  under  the  dominion  of  the 
central  nervous  system,  and  if  the  control  so  exercised  is 
diminished  there  may  be  a  tendency  to  increased  waste  of  tissue, 
just  as  there  is  in  a  paralysed  limb.  But  the  degree  in  which 
the  nervous  system  exercises  its  functions  differs  enormously  in 
different  persons,  and  so  it  is  not  altogether  incredible  that  the 
degree  in  which  bodily  waste  is  controlled  may  differ  also. 

Be  this  as  it  may,  there  is  no  more  practical  fact  in  dietetics  than 
the  different  results  which  the  same  food,  either  in  quantity  or  in 
kind,  produces  in  ditTerent  persons,  and  it  has  to  be  constantly  borne 

1  For  a  criticism  of  this  view  see  Rubner's  '  Beitrage  zur  Ernahrung  im  Knabetj- 
alter  '  (Berlin,  1902). 


53  FOOD  AND  DIETETICS 

in  mind  in  regulating  the  diet  of  the  sick.  A  study  of  the  habits 
of  different  nationalities  reveals  the  same  thing.  The  German  is 
notoriously  a  larger  feeder  than  the  Frenchman,  and  Americans 
seem  to  consume  more  food  per  head  than  Englishmen  in  the 
same  conditions  of  life.  Even  granting,  which  might  be  dis- 
puted, that  the  output  of  work  and  energy  is  greater  per  in- 
dividual in  America  than  in  Europe,  the  difference  is  not  entirely 
explained,  and  may  perhaps  rest  on  some  inherent  constitutional 
cause.  Anyhow,  a  consideration  of  facts  such  as  these  should 
warn  one  of  the  dangers  of  dogmatism  in  matters  of  diet.  We 
can  and  may  lay  down  rules  as  to  the  kind  and  amount  of  food 
required  under  different  circumstances,  but  we  are  treading  on 
dangerous  ground  when  we  come  to  apply  these  rules  to  individual 
cases.  In  the  matter  of  diet  every  man  must,  in  the  last  resort,  be 
a  law  unto  himself ;  but  he  should  draw  up  his  dietetic  code  intelli- 
gently, and  apply  it  honestly,  giving  due  heed  to  the  warnings  which 
Nature  is  sure  to  address  to  him  should  he  at  any  time  transgress. 

Having  considered  the  kind  and  quantity  of  food  required  in 
health,  and  the  way  in  which  these  are  affected  by  various  bodily 
conditions  and  states  of  life,  we  may  now  glance  for  a  moment  at 
the  general  effects  of  an  excessive  or  a  deficient  supply  of  food 
respectively. 

Overfeeding. — It  is,  perhaps,  no  exaggeration  to  say  that  the 
tendency  of  civilized  peoples,  and  especially  of  the  upper  classes  in 
civilized  society,  is  to  eat  too  much.  Feeding  is  pleasurable  as  well 
as  necessary,  and  when  the  necessities  of  the  body  have  been  sup- 
plied, the  process  is  apt  to  be  continued  merely  for  the  sake  of  the 
pleasure  which  it  affords.  Now,  a  moderate  excess  of  food  is  prob- 
ably harmless,  if  not  actually  beneficial.  It  is  not  safe  to  sail  too 
near  the  wind  in  matters  of  diet.  As  a  French  writer  has 
paradoxically  put  it :  '  Pour  avoir  assez  il  faut  avoir  trop.'  For  it 
is  well  to  have  some  reserve  in  the  body  which  can  be  called  upon 
if  one  is  compelled  for  any  reason  to  go  for  some  time  without  any 
food  at  all.  The  presence  of  such  a  reserve  can  only  be  insured  by 
the  habitual  consumption  of  ratlier  more  food  than  is  reqmred  to 
meet  the  bare  necessities  of  the  body.  It  is  in  this  way,  too,  that 
the  occasional  indulgence  in  an  unusually  heavy  meal  can  be 
justified.  There  are  some,  for  instance,  who  see  in  the  large  Sunday 
dinner  of  the  workman  a  partial  provision  for  the  wants  of  the  whole 
week. 

Leaving  aside  the  consideration  of  this  surplus,  which  can  hardly 
be  described  as  an  excess,  one  has  to  look  at  the  results  of  acute  and 


OVERFEEDING  53 

chronic  overfeeding  separately.  The  injurious  effects  of  consuming 
a  great  excess  of  food  at  one  time  are  local  rather  than  remote. 
They  fall  chiefly  upon  the  digestive  organs.  The  overburdened 
stomach  may  relieve  itself  by  vomiting,  or,  if  the  food  is  passed  on 
into  the  intestine,  it  is  apt  to  undergo  decomposition  before  it  is  all 
absorbed,  and  be  carried  off  by  diarrhoea.  That  these  effects  may 
sometimes  be  sufficiently  severe  is  evidenced  by  the  fact  that  people 
have  been  known  to  die  of  a  *  surfeit,'  though  in  modern  days  such  a 
result  must  be  regarded  as  very  rare,  always  excepting  those  instances 
in  which  even  moderate  overloading  of  the  stomach  may  have  too 
much  hampered  the  action  of  a  feeble  heart. 

If  the  process  of  absorption  goes  on  too  rapidly  for  assimilation  to 
keep  pace  with  it,  the  blood  seems  to  be  able  to  rid  itself  of  some,  at 
least,  of  the  surplus  products  of  digestion  by  aid  of  the  kidneys. 
Thus,  a  great  excess  of  protein  in  the  food  may  give  rise  to  transient 
albuminuria,  while  sugar  may  temporarily  appear  in  the  urine  after 
an  extravagant  consumption  of  carbohydrates.  This  method  of 
adjusting  the  balance,  however,  seems  to  be  one  which  is  but 
seldom  had  recourse  to. 

The  general  results  of  habitual  or  chronic  overfeeding  are  more 
insidious,  and  seem  to  vary  with  the  nutritive  ingredient  which  is 
specially  indulged  in.  If  this  be  carbohydrate  or  fat,  the  surplus  is 
simply  stored  up  in  the  form  of  fat,  and  obesity  results.  In  the  case 
of  protein  such  storage  is  hardly  possible,  for  so  great  is  the  tendency 
of  'nitrogenous  equilibrium  '  to  assert  itself  that  the  body  can  only 
'  lay  on  '  protein  for  very  short  periods,  unless  the  process  of  growth 
is  still  going  on.  What  usually  appears  to  happen  is  that  the 
surplus  protein  is  split  up  into  two  portions,  one  of  which  contains 
most  of  the  carbon  and  is  probably  converted  into  fat  and  stored  in 
that  form,  while  the  nitrogen-containing  part  is  broken  down,  but 
not,  perhaps,  very  rapidly  and  completely  ;  so  that  the  products  which 
represent  the  intermediate  steps  in  its  destruction  circulate  for  some 
time  in  the  blood  before  being  excreted  in  the  form  of  urea.  It  may 
be  that  some  of  these  products  are  concerned  in  the  production  of 
such  conditions  as  granular  degeneration  of  the  kidneys,  high 
arterial  tension,  gout,  and  rheumatism ;  but  that  is  a  point  on  which 
it  is  not  yet  advisable  to  speak  very  dogmatically.  It  must  be 
remembered,  too,  in  this  connection  that  an  excess  of  protein  sparers 
in  the  blood  may  produce  very  similar  results  to  an  excess  of 
protein  itself  by  shielding  the  latter  from  complete  and  rapid 
oxidation. 

Underfeeding. — It  is  astonishing  how  long  the  body  can  go  without 


54  FOOD  AND  DIETETICS 

food  provided  a  due  supply  of  water  is  obtainable.  Lunatics  have 
been  known  to  refuse  food  for  four  or  five  weeks  at  a  stretch,  and 
the  experience  of  professional  fasters  shows  that  long  periods  of 
starvation  can  be  borne  with  impunity.  Experiment,  indeed,  has 
shown  that  it  is  only  when  the  weight  of  the  body  has  fallen  to  one- 
half  or  one-third  its  original  amount  that  death  from  inanition  ensues. 
It  is  well  to  remember  these  facts  when  dealing  with  cases  of  acute 
disease.  A  doctor  is  very  apt  to  flatter  himself  that  he  is  keeping  a 
patient  alive  by  rectal  feeding,  for  example,  when  all  the  time  the 
patient  is  really  Hving  on  his  own  tissues.  Nor  need  one  be  unduly 
alarmed  if  a  well-nourished  patient  is  unable  to  take  any  food  at  all 
for  a  few  days.  His  own  reserves  will  be  able  to  tide  him  over  the 
emergency  without  much  injury. 

Of  chronic  or  habitual  underfeeding  as  a  whole  it  may  safely  be 
said  that  it  is  more  injurious  than  the  opposite  condition  of  intem- 
perance in  food.  One  has  to  recognise  also  that  a  relative  lack  of 
one  nutritive  constituent  is  probably  commoner  than  a  deficiency  of 
all,  or,  in  other  words,  that  an  ill-balanced  diet  is  more  frequently 
met  with  than  one  which  is  defective  all  round.  As  nitrogen  is  the 
element  of  which  the  body  is  mainly  built  up,  a  lack  of  protein  in  the 
food  seems  to  be  more  injurious  than  a  shortcoming  in  respect  of 
carbohydrate  or  fat.  As  this  point  has  already  been  referred  to 
(p.  24),  it  need  only  be  repeated  here  that  an  insufficient  supply  of 
protein  leads  to  imperfect  tissue  repair,  more  especially,  perhaps,  of 
the  muscles  and  blood  ;i  that  it  causes  the  body  to  become  unduly 
watery,  whence  the  pallor  and  puffiness  of  the  underfed ;  and  that 
the  combined  effect  of  these  results  is  to  produce  a  lowering 
of  the  power  of  resistance  to  unfavourable  influences,  including 
disease.^ 

It  must  not  be  concluded  that  merely  because  a  man  is  fat  he 
cannot  at  the  same  time  be  underfed.  On  the  contrary,  obesity  is 
quite  compatible  with  an  insufficient  supply  of  nitrogenous  nutri- 
ment, and  many  of  the  most  intractable  cases  of  corpulence — those, 
namely,  in  which  the  patient  is  pale  and  fiabby  as  well  as  fat — are 
just  those  in  which  the  nitrogenous  tissues  of  the  body  are  to  be 
regarded  as  being  in  a  state  of  imperfect  formation  and  repair.     It 

^  For  experimental  evidence,  see  Subbotin,  Zeitsch.  fi'ir  Biologic,  1871,  vii., 
p.  185. 

2  For  information  on  the  part  played  by  habitual  underfeeding  in  the  produc- 
tion of  physical  deterioration,  see  evidence  by  the  writer  and  others  in  the  Report 
of  the  Interdepartmental  Committee  on  Physical  Deterioration  (London :  Eyre 
and  Spottiswoode,  1904). 


UNDERFEEDING  55 

is  probably  for  this  reason  that  fat  persons  often  stand  depletory 
measures,  such  as  purging  and  bleeding,  worse  than  those  who  are 
in  appearance  not  so  well  nourished. 

The  effects  of  insufficient  feeding  in  diminishing  resistance  to  cold 
have  already  been  alluded  to  (p.  49),  and  were  strikingly  seen  in 
some  episodes  of  the  American  Civil  War,  a  detailed  account  of 
which  has  been  provided  by  Flint. ^  Its  effects  in  producing  liability 
to  disease  were  well  illustrated  in  the  outbreaks  of  relapsing  fever 
and  typhus  which  followed  the  potato  famine  in  Ireland^  in  the  early 
part  of  this  century,  and  similar  results  have  repeatedly  been  wit- 
nessed in  India  and  elsewhere,  fever  and  plague  dogging  the  foot- 
steps of  famine.  It  has  also  been  pointed  out  that  exposure  to 
infection  is  specially  apt  to  be  dangerous  on  an  empty  stomach,  as, 
for  example,  before  breakfast,  a  fact  which  it  is  important  for 
doctors  and  nurses  to  bear  in  mind. 

The  tubercle  bacillus  seems  to  find  a  peculiarly  favourable  soil 
in  ill-nourished  persons.  The  association  between  bad  feeding  and 
such  diseases  as  phthisis  and  scrofula  is  well  established,  while 
an  improvement  in  nutrition  is  not  infrequently  followed  by 
their  cure.  This  may  be  the  reason  why  diabetics,  who  live  in  a 
chronic  state  of  partial  starvation,  are  so  liable  to  tuberculosis,  and 
tall  men,  who,  for  reasons  already  discussed,  have  less  food  to  spare 
than  their  fellows  of  less  stature,  are  believed  to  be  more  subject  to 
consumption  than  the  latter  are. 

Epidemic  ophthalmia  is  another  disease  which  seems  prone  to 
select  the  underfed  as  its  victims,  and  it  might  be  well  when  it 
breaks  out,  as  it  is  so  apt  to  do,  among  the  children  of  Poor  Law 
schools  and  other  public  institutions,  to  look  more  to  the  possibility 
of  defective  diet  and  less  to  overcrowding  as  the  cause. 

It  is  considerations  such  as  these  which  entitle  one  to  regard  the 
repeal  of  the  Corn  Laws,  which  has  done  so  much  to  cheapen  food 
in  this  country,  as  a  hygienic  quite  as  much  as  an  economic  measure, 
and  the  diminished  death-rate  which  has  been  so  conspicuous  in  the 
latter  part  of  the  last  century  may  have  had  more  to  do  with  it 
than  one  commonly  thinks.^ 

There  is  reason  to  fear,  however,  that  large  sections  of  the  com- 

^  '  Physiology  of  Man,'  New  York,  1867,  p.  35. 

'  See  Life  of  William  Stokes  in  '  Masters  of  Medicine  '  Series,  p.  no  ct  scq. 

*  For  particulars  of  the  enormous  all-round  improvement  which  has  taken 
place  in  the  abundance  and  variety  of  the  diet  of  agricultural  labourers  in  this 
country  in  the  last  half-century,  see  a  paper  on  '  Agricultural  Wages  in  England  and 
Wales  during  the  Last  Fifty  Years,'  by  A.  Wilson  Fox  (Journ.  Roy.  Statist.  Soc, 
1903,  Ixvi.  273).     Similar  information  will  be  found  in  the  volume  entitled  '  Labour 


56  FOOD  AND  DIETETICS 

munity   in   this   country  are   still    habitually  underfed.     Observa- 
tions   on    the    diet    of    labourers    in    Edinburgh  ^   showed   that   it 
contained    on    an    average   only    1077    grammes    of    protein,    as 
against  Atwater's  standard  of  125  grammes,  and  an  energy  value 
of  only  3,228  Calories,  as  opposed  to  the  3,500  which  he  believed 
to  be  necessary  for  a  labouring   man.      Mr.   Seebohm  Rowntree's 
inquiries   into  the  diet  of  a  corresponding  class  in  York^  yielded 
similar  results,  the  energy  value  being  17  per  cent.,  and  the  protein 
average  no  less  than  29  per   cent,   below  standard  requirements. 
There  is  urgent  need  for  more  extended  studies  on  similar  lines  to 
these.'     Meanwhile,  it  may  be  pointed  out  that  the  defects  above 
indicated  are  due  not  so  much  to  poverty  as  to  ignorance  ;  not  to 
buying  too   little   food,  but  to  buying   the  wrong   articles.      The 
Edinburgh  investigators  were  of  opinion  that  in  order  to  improve 
the  dietary  of  the  labouring  classes  the  following  principles  should 
be  instilled  into  them  : 

1.  That  a  diet  of  tea  and  bread  or  of  tea,  bread,  and  butter  (the 
lazy  diet)  is  faulty. 

2.  That  the  faults  of  the  tea  and  bread  diet  can  be  corrected  by 
the  free  use  of  meat,  eggs,  or  other  animal  food,  but  that  this  mode 
of  correction  is  expensive. 

3.  That  the  faults  can  also  be  corrected  by  the  free  use  of  oatmeal 
with  milk,  or  of  peas  or  beans,  without  extra  cost. 

The  bad  eflfects  of  underfeeding  fall  most  heavily  upon  the  young, 
for  the  greater  the  demand  on  the  part  of  the  body  for  food,  the  more 
severely  is  any  deficiency  felt.*  The  recognition  of  this  fact  is  as  old 
as  Hippocrates,  who  devoted  a  special  aphorism  to  the  statement  of 
it.  '  Old  men,'  it  runs,  '  bear  want  of  food  best ;  then  those  that  are 
adults  ;  youths  bear  it  least,  most  especially  children,  and  of  them 
the  most  lively  are  the  least  capable  of  enduring  it. ' 

and  Protection,'  edited  by  H.  W.  Massingham  (London  :  T.  Fisher  Unwin,  1903). 
For  statistics  on  the  fall  in  the  price  of  food  in  recent  years,  see  Memoranda,  etc., 
on  British  and  Foreign  Trade  and  Industrial  Conditions  (London :  Eyre  and 
Spottiswoode,  1903). 

1  Loc.  cit. 

^  '  Poverty  :  A  Study  of  Town  Life  '  (London  :  Macmillan  and  Co.,  Ltd.,  1903, 
new  edition,  p.  234). 

^  For  earlier  studies  of  diets  in  this  country,  in  which,  however,  the  carbon 
and  nitrogen  standard  was  employed,  see  '  On  the  Dietaries  of  Scotch  Agricultural 
Labourers'  and  'On  the  Economic  Condition  of  the  English  Agricultural 
Labourer,'  by  Robert  Hutchison,  F.R.S.E.  {Trans,  of  the  Highland  and  Agri- 
cultural  Society  of  Scotland,  1867  and  1S71).  Also  Oliver,  '  The  Diet  of  Toil,'  a 
paper  read  at  the  Congress  of  Hygiene  and  Demography,  Buda-Pesth,  Sep- 
tember, 1894.  For  references  to  some  more  recent  dietary  studies  in  this  country 
see  p,  34. 

*  See  '  Feeding  in  Relation  to  the  Health  of  the  Young, 'by  James  Niven,  M.A,, 
M.B.  (Louden  and  Manchester  :  Sherratt  and  Hughes,  1904). 


UNDERFEEDING  57 

The  remote  results  of  underfeeding  are  not  less  injurious  than  its 
more  immediate  effects.  Amongst  such  results,  impairment  of 
digestive  power  is  very  conspicuous. ^  The  danger  of  stuffing  a 
starving  man  is  notorious,  but  even  in  chronic  underfeeding  the 
same  weakening  of  the  digestive  organs  is  observed.  It  is  often  seen 
in  dyspeptics.  The  more  their  nutrition  fails  through  not  eating, 
the  less  they  are  able  to  digest,  and  the  first  step  in  curing  their 
stomach  troubles  must  often  be  in  the  direction  of  compelling  them 
to  eat  more. 

Another  of  these  remote  dangers  is  in  the  influence  of  imperfect 
feeding  upon  the  mind.  I  refer  not  merely  to  a  lowering  of  mental 
power,  but  to  that  feeling  of  dissatisfaction,  discomfort,  and  depres- 
sion, culminating  sometimes  in  madness  and  hallucinations,  which 
imperfect  nutrition  of  the  brain  is  apt  to  produce. 

'  A  hungry  man  is  an  angry  man,'  and  the  proverbial  good 
nature  of  the  Englishman  may,  perhaps,  be  associated  with  the  fact 
that,  as  a  rule,  he  is  full  fed.  The  dangers  here  alluded  to  have 
been  eloquently  described  by  Dr.  King  Chambers^  in  the  following 
passage,  with  which  I  may  close  this  chapter  : 

*  Deficient  diet,  like  all  morbid  conditions,  both  corporeal  and 
mental,  is  a  vitiating  and  degenerating  influence.  Famine  is  naturally 
the  mother  of  crimes  and  vices,  not  only  of  such  sort  as  Avill  satiate 
the  gnawing  desire  for  food,  but  of  general  violence  and  lawlessness, 
ill-temper,  avarice,  lust,  and  cruelty. 

•The  love  of  purposeless  destruction  exhibited  by  the  Parisian 
Communists  in  our  own  day  may  be  fairly  credited  to  deficient 
food.  No  well-fed  people  could  have  wrecked  the  Vendome  Column 
or  burnt  the  Town  Hall  and  Tuileries,  of  which  they  were  so 
proud.  They  were  like  hungry  children  smashing  their  dolls.  And 
Thucydides,  Boccaccio,  and  Defoe  are  all  agreed  as  to  the  hideous 
wickedness  exhibited  at  Athens,  Florence,  and  London  during  their 
famine-fevers.  The  exceptional  instances  are  those  where  individuals 
or  nations  have  conquered  by  courage  and  self-restraint  their  natural 
selfishness,  and  have  made  the  interests  of  others  paramount  to 
their  own.  Am  I  blinded  by  love  of  my  country,  or  may  I 
justly  quote  the  history  of  the  Lancashire  cotton-famine  as  a  case 
in  point  ?' 

*  It  is  an  interesting  question  whether  the  efifect  of  town  life  in  impairing 
digestive  power  may  not  be  partly  responsible  for  the  habitual  underfeeding  so 
often  found  in  the  industrial  section  of  urban  communities.  It  is  possible,  in  other 
words,  that  the  town  worker  may  in  many  cases  be  incapable  of  digesting  enough 
food  to  keep  him  in  an  ideal  state  of  physical  efficiency. 

*  'Manual  of  Diet  in  Health  and  Disease,'  second  edition,  1876,  p.  223, 


[  58  1 


CHAPTER  IV 

ANIMAL  rOODS 

In  previous  chapters  we  have  dealt  with  foods  in  general.  We 
have  studied  the  nature  and  uses  of  their  nutritive  constituents,  the 
standards  by  which  one  judges  of  their  relative  values,  the  amount 
of  food  required  to  maintain  the  body  in  a  state  of  health,  and  the 
directions  in  which  this  amount  must  be  modified  in  accordance 
with  various  influences  and  conditions.  We  have  also  glanced  at 
the  general  results  of  over  and  under  feeding.  In  this  and  a  number 
of  succeeding  chapters  we  shall  undertake  the  study  of  individual 
foods  in  detail,  and  in  dealing  with  each  shall  consider  (i)  its  physical 
structure  and  chemical  composition  ;  (2)  its  behaviour  in  the  stomach 
and  intestine ;  (3)  its  nutritive  value  in  the  body;  (4)  its  true  economic 
worth. 

We  may  begin  our  studies  with  foods  derived  from  the  animal 
kingdom ;  but  it  will  be  well  to  defer  the  consideration  of  the 
general  characters  of  the  group  as  a  whole  until  we  are  in  a  position 
to  contrast  them  with  the  vegetable  foods. 

A  convenient  classification  of  the  animal  foods  is  as  follows  : 

1.  Meat,  including  the  several  varieties  of  butcher's  meat,  poultry, 
game,  and  '  oflFal.' 

2.  Gelatin  and  the  foods  prepared  from  it  (jellies). 

3.  Soups,  beef-extracts  and  beef-powders,  beef-tea  and  beef-juices. 

4.  Fish  and  its  allies. 

5.  Milk  and  its  derivatives,  including  cream,  butter,  and  cheese. 

6.  Eggs. 

I.  Meat. 

We  may  look  first  at  the  physical  structure  or  architecture  of 
meat  (Fig.  4). 

If  one  examines  a  piece  of  boiled  meat,  it  will  be  found  that  it  can 
easily  be  torn  into  a  number  of  long,  stringy  fibres.     On   micro- 


ANIMAL  FOODS 


59 


scopic  examination,  these  would  be  found  to  be  made  up  in  their 
turn  of  bundles  of  microscopic  tubes,  known  to  the  histologist  as 
muscle  fibres.  The  fibres  vary  in  length  in  different  kinds  of  meat. 
Sometimes  they  are  short,  as  in  the  breast 
of  a  chicken ;  at  other  times  they  are 
much  longer,  as  in  the  leg  of  a  crab  ;  and 
the  shorter  they  are,  the  more  tender  and 
easily  digested  the  meat  is.  Meat  should 
be  cut  or  carved  at  right  angles  to  the  long 
axis  of  the  fibres.  It  is  then  more  easily 
cliewed,  and,  the  contents  of  the  tubes 
l)eing  exposed,  the  flavour  is  increased, 
while  the  action  of  the  digestive  juices  is 
facilitated. 

The  walls  of  the  tubes  consist  of  an 
albuminoid  substance  (elastin),  while  the 
connective  tissue  which  holds  together  the 
fibres  is  chiefly  composed  of  a  material 
called  'collagen,'  which  yields  gelatin  on 
boiling.  The  older  an  animal  is,  and  the 
more  work  its  muscles  have  had  to  per- 
form, the  denser  is  the  connective  tissue 
and  the  thicker  the  walls  of  the  tubes. 
The  latter  fact  was  long  ago  pointed  out 
by  Dr.  Kitchiner  in  his  '  Cook's  Oracle.' 
'  That    exercise    produces    strength    and 

PRESENTATION     OF     THE  firmness  of  fibre,'  he  says,  '  is  excellently 

Structure   of  Meat.  ,,  i-c    i     •        .^i  11  3 

well   exemplified    m    the   woodcock    and 

«,  Muscle  fibres ;  &,  Fat  cells;  ,   .,  ^,         r  ^.  ,      ,, 

c.  Connective  tissues.        partridge.      The    former    flies    most,    the 

latter  walks  ;  the  wing  of  the  woodcock  is 

always  very  tough,  of  the  partridge  very  tender ;    hence  the  old 

doggerel  distich : 

If  the  Partridge  had  but  the  Woodcock's  thigh. 
He'd  be  the  best  bird  that  e'er  doth  fly.' 

Embedded  in  the  connective  tissue  between  the  fibres  is  a  variable 
amount  of  fat.  Sometimes  it  is  almost  entirely  absent — e.g.,  in  most 
forms  of  game  and  in  the  breast  of  the  chicken ;  at  other  times  the 
amount  of  fat  so  placed  is  quite  abundant.  This  is  the  case  in  pork, 
in  highly-fattened  beef  or  mutton,  and  in  swimming  birds,  such  as 
the  duck  and  goose,  which  require  a  large  store  of  fat,  both  to  lighten 
the  body  and  as  a  source  of  heat.     A  large  amount  of  fat  tends  to 


Fig.  4. 


-Diagrammatic  Re- 


6o  FOOD  AND  DIETETICS 

diminish  the  digestibility  of  meat,  apparently  by  forming  a  sort  of 
waterproof  coating  around  the  fibres  and  hindering  their  solution  by 
the  gastric  juice,  and  it  is  notorious  that  pork,  duck,  and  goose  are 
rather  indigestible  forms  of  flesh. 

The  contents  of  the  microscopic  tuhes  or  muscle  fibres  consist  of 
water  holding  in  solution  proteins,  salts,  and  the  substances  known 
as  '  extractives,'  the  whole  constituting  muscle-juice.  The  younger 
the  animal,  the  more  water  does  its  flesh  contain,  and  the  lower  is 
its  nutritive  value.  This  may  be  the  explanation  of  the  German 
saying,  *  Calf-meat  is  half-meat.' 

The  chief  proteins  which  the  juice  contains  are  myosin,  muscle 
albumin,  and  haemoglobin,  the  first  being  the  most  important. 
Myosin  has  the  property  of  clotting  after  death,  the  hardening  of 
the  muscle  which  results  being  known,  it  will  be  remembered,  as 
rigor  mortis,  or  death -stifiiening.  Meat  in  that  condition  is  tough, 
and  accordingly,  if  tenderness  is  desired,  the  meat  should  be  eaten 
either  immediately  after  the  animal  is  killed,  and  before  rigor  mortis 
has  had  time  to  set  in,  or  else  it  should  be  allowed  to  hang  till  the 
rigor  has  passed  off".  The  disappearance  of  rigor  is  due  to  a  re- 
solution of  the  myosin  by  the  development  of  acids,^  and  to  a  partial 
digestion  of  it  by  the  traces  of  pepsin  which  muscle  contains.  The 
process  must  be  regarded  as  an  early  stage  of  putrefaction,  and,  as 
is  well  known,  if  the  meat  be  allowed  to  hang  for  some  time  longer 
it  becomes  '  high.' 

The  acids  which  develop  in  meat  on  hanging  aid  the  gelatinization 
of  the  connective  tissue  which  occurs  on  boiling,  and  also  improve 
Its  flavour  by  removing  the  rather  insipid  flatness  of  taste  which 
characterizes  very  fresh  meat.  In  the  flesh  of  animals  which  have 
undergone  great  muscular  exertion  immediately  before  being  killed 
there  is  a  considerable  quantity  of  acid  present  even  at  the  time  of 
death.  Hence  the  flesh  of  hunted  animals  is  of  a  superior  flavour, 
and  in  less  humane  ages  and  countries  attempts  have  been  made  to 
develop  this  flavour  in  domestic  animals  artificially  by  urging  them 
to  frantic  exertions  before  slaughter.  Another  way  of  producing 
these  effects  by  artificial  means  is  by  soaking  the  meat  in  vinegar 
and  water  for  a  short  time.  This  is  found  to  improve  the  flavour  of 
fresh  meat,  as  well  as  its  tenderness.  It  is  partly  for  the  same  reason 
that  the  use  of  vinegar  favours  the  digestibility  of  the  hard  muscles 
of  the  crab  and  lobster. 

The  amovmt  of  haemoglobin,  or  red  colouring  matter,  in  the  juice 
varies  greatly  in  different  kinds  of  meat,  and  is  usually  less  in 
*  Sarcolactic  acid  and  acid  phosphates. 


CONSTITUENTS  OF  MEAT  6i 

amount  in  that  obtained  from  young  animals.  It  is  of  importance 
as  containing  iron.  Haemoglobin  is  also  found  in  the  small  blood- 
vessels which  form  a  network  around  the  fibres  of  meat.  In  animals 
which  have  been  bled  to  death  it  is  much  diminished  in  amount  at 
altogether  removed  ;  hence  the  pallor  of  veal. 

The  chief  mineral  substances  found  in  the  juice  of  meat  are  phos- 
phoric acid  and  potash.  Meat  must  be  regarded  as  one  of  the 
principal  sources  of  these  valuable  building  materials  in  the  diet, 
and  if  they  are  insufficiently  supplied,  the  muscles  are  flabby  and 
badly  developed. 

Last,  but  not  least,  of  the  substances  contained  in  solution  in  the 
juice  of  meat  are  the  extractives.  These  are  so  called  because  they 
can  be  *  extracted  '  from  meat  by  means  of  boiling  water,  and  are 
familiar  to  everyone  as  the  dark  brown,  sticky  material  which  con- 
stitutes the  chief  part  of  Liebig's  Extract.  We  shall  have  much  to 
learn  about  these  extractives  later  on,  but  it  may  be  stated  here  that 
their  exact  chemical  nature  is  to  a  large  extent  unknown,  that  they 
have  no  direct  nutritive  value,  but  are  of  importance  as  being  the 
chief  cause  of  the  characteristic  taste  of  meat,  a- .  ".  that,  therefore,  when 
they  are  removed,  as  they  are,  for  example,  on  prolonged  boiling, 
the  meat  becomes  flavourless  and  insipid.  Further,  it  would  appear 
that  the  characteristic  flavours  of  the  different  kinds  of  meat  are  due 
to  minute  differences  in  the  amount  and  kind  of  the  extractives 
present.  The  age  of  the  animal  and  the  way  in  which  it  is  fed  are 
of  great  importance  in  this  connection.  The  flesh  of  full-grown 
animals  is  richer  in  extractives  and  has  a  fuller  flavour  than  the 
flesh  of  those  which  are  immature,  which  explains  why  we  eat 
lamb  with  mint  sauce  and  add  spices  to  veal.  The  influence  of 
feeding,  on  the  other  hand,  is  well  illustrated  by  all  forms  of  game. 
The  flesh  of  wild  rabbits,  which  eat  aromatic  herbs,  especially 
thyme,  has  a  much  finer  flavour  than  that  of  rabbits  which  are  fed 
by  hand,  and  a  slice  of  wild  duck  is  generally  admitted  to  be  a  more 
tasty  morsel  than  a  piece  of  the  bird  reared  in  a  farmyard.  Every- 
one knows,  too,  how  '  fishy '  sea-birds  taste,  how  superior  hill 
mutton  is  to  its  turnip-fed  substitute,  and  how  in  grouse  or  caper- 
cailzie one  can  detect,  as  it  were,  an  echo  of  the  aroma  of  the 
heather-tops  or  pinewoods  amongst  which  these  birds  live. 

The  chemical  composition  of  meat  varies  considerably,  depending  as 
it  does  on  the  particular  '  cut '  examined,  on  the  breed  of  the  animal,  and 
on  the  degree  to  which  it  has  been  fattened.  It  must  be  noted,  also,  that 
by  no  means  the  whole  of  ordinary  butcher's  meat  consists  of  edible 
matter,  a  large  part  being  made  up  of  bone,  gristle,  tendon,  and 


62  FOOD  AND  DIETETICS 

other  inedible  portions.     In  an  average  piece  of  meat  these  waste 

matters  may  be  reckoned  at   15  per  cent,  of  the  Avhole,  and  the 

proportions   of  the   constituents   in  the   edible   part   are   about   as 

follows  (Konig)  : 

Water  75  to  77  per  cent. 

Muscle  fibres  ..         ..  131018 

Connective  tissue  . ,  . .  2  to  5 

Fat ^  to  3 

Ash o"8  to  1-8 

Extractives . .         . .         . .  ^ 

Oth'^r  analyses  represent    the  proportions  of  the  chemical   sub- 
stances present  thus : 


100  Parts  of  Lean  Beef  without  Visible 

Fat  {Bischoff  and  Voit). 

Protein     ..  ,.         ..     iS  36 

Gelatin     ..  ..  ..       1-64 

Fat  ..  .,  ..       o go 

Extractives  .,         ..       igo 

Ash  ..  ..  ..       1-30 

Water       ..  ..  ..     7590 


100  Parts  of  Dry  Substance 
(Riibner). 
Syntonin,  myosin,  and  gelatin    701 
Hasmoglobin  and  serum  albu- 
min     . .  . .  . .  . .     855 

Muscle  albumin  ..         ..     313 

Extractives        ..  ..  ..    1268 

Ash         550 


The  effects  of  fattening  are  shown  in  the  following  table,  in  which 

the  composition  of  lean,  medium,  and  very  fat  beef  are  stated  in 

round  numbers : 

Water.  Nitrogenous  Matter}  Fat.  A  sh. 

Lean..         ..         765                       21                         15  i 

Medium       ..         73                            20*5  5"5  i 

.     Very  fat       . .         53                            17  29  i 

The  chief  points  to  note  in  this  table  are  :  (i)  The  large  amount 
of  water  which  meat  contains.  About  three-quarters  of  its  total 
weight  is  made  up  of  water,  or,  stated  otherwise,  i  pound  of 
meat  contains  |  pound  water  and  ^  pound  of  nutriment.  It  has 
been  already  pointed  out  that  the  flesh  of  young  animals  is  relatively 
richest  in  water.  (2)  The  relation  between  water  and  fat.  The 
more  there  is  of  the  latter  present,  the  less  there  is  of  the  former  ;  in 
other  words,  when  fat  is  deposited  in  a  muscle,  it  replaces  water,  and 
not  protein,  and  so  the  gain  in  nutritive  value  is  an  absolute  one, 
and  is  not  attained  at  the  expense  of  a  loss  of  nitrogenous  con- 
stituents. The  above  analyses  refer  especially  to  beef ;  the  composi- 
tion of  the  other  commoner  sorts  of  iii^cit  and  some  varieties  of 
game  may  be  graphically  represented  as  follows  :2 

*  'Nitrogenous  matter'  is  the  figure  obtained  by  multiplying  the  amount  of 
nitrogen  in  100  parts  by  6'25  ;  i.e.,  it  is  assumed  that  it  is  all  protein.  In  rerdity 
15  per  cent,  of  the  total  nitrogen  is  present  in  the  form  of  extractives,  the 
amount  of  which  can  be  calculated  by  multiplying  their  nitrogen  by  312 
(Stutzer's  factor). 

*  Most  of  the  analyses  from  which  the  diagram  is  constructed  are  by  Konig 
and  Stutzer.     The  analysis  of  lamb  is  from  Atwater,  that  of  bacon  from  Church. 


CONSTITUENTS  OF  MEAT 


63 


WATER.I        I 


PROTEIN  & 
GELATINE. 


FAT. 


ASH. 


The    following   table  shows   the   composition  of  the  commoner 
poultry  :  ^ 

COMPOSITION  OF  POULTRY. 


Fowl,  young : 

Dark  meat . .         , .         . .  . , 

Light  meat  . .         . . 

Giblets       . .         . .         , . 
Turkey : 

Dark  meat . .  . .         . . 

Light  meat 

Giblets 
Duck: 

Meat,  not  including  breast  or  giblets . 

Breast 

Giblets 
Goose : 

Meat,  not  including  giblets 

Giblets  


Water. 


70-1 

70'3 
710 

57-0 
63-9 
567 

55-5 
739 
732 

51-8 
700 


Protein. 


208 
21-9 
ig-S 

21'4 

257 
177 

17-4 
223 
179 

i6-2 

20"I 


Fat. 


8-2 

7-4 
6-4 

20-6 

94 
23-5 

26'I 

23 
5-0 

31*5 
8-2 


Ash. 


1-2 
i"i 
I  "3 

I  "3 

I'2 

10 
13 

1-8 

10 
17 


I  United  States  Department  of  Agriculture,  Farmers'  Bull.  No.  234. 


54  FOOD  AND  DIETETICS 

It  must  be  clearly  realized  that  these  results  are  merely  approxi- 
mative, and  may  vary  considerably  in  different  cases.  Thus, 
in  very  young  calves  the  amount  of  water  in  the  flesh  may  be 
80  instead  of  only  71  per  cent.  The  relative  proportions  of  gelatin 
and  protein  also  fluctuate  considerably.  The  proportion  of  the 
former  is  highest  in  the  flesh  of  young  animals — hence  the  value 
of  veal  as  a  basis  for  soups — and  is  lowest  in  game.  As  regards 
the  amount  of  the  extractives,  but  few  data  are  available,  but  the 
latest  investigations  tend  to  show  that  the  red  meats  are  richest  in 
these  constituents.^ 

Hitherto  we  have  been  dealing  with  the  structure  and  composition 
of  meats  in  their  raw  state,  and  we  must  now  direct  our  attention  to 
the  changes  which  are  effected  in  them  by  cooking.  The  full  con- 
sideration of  this  subject  may  be  conveniently  deferred  to  another 
chapter  (Chapter  XXII.),  but  at  present  one  may  note  that  the  general 
effect  of  cooking  on  the  structure  of  meat  is  (i)  to  loosen  the  fibres  by 
converting  the  connective  tissue  which  holds  them  together  into 
gelatin,  and  (2)  to  remove  some  of  the  fat,  the  exact  proportion 
lost  depending  on  its  melting-point,  and  being  higher  in  cake-fed 
than  in  pasture-reared  animals. 

The  chief  effect  of  cooking  on  the  chemical  composition  of  meat  is 
to  diminish  the  amount  of  water  which  it  contains.  This  results, 
curiously  enough,  even  when  the  meat  is  boiled.  This  is  important, 
for  it  means  a  very  considerable  increase  in  the  nutritive  value  of 
cooked,  as  compared  with  raw,  meat,  a  result  which  is  the  very 
reverse  of  that  which  follows  the  cooking  of  vegetables  (p.  405 ).  In 
consequence  of  this  loss  of  water,  an  ordinary  plateful  of  cooked 
meat,  weighing  4  ounces,  may  be  regarded  as  equivalent  to  5  ounces 
of  raw  meat.  Another  effect  of  cooking  on  the  chemical  composition 
of  meat  is  the  removal  of  part  of  the  extractives.  This  is  most 
marked  when  boiling  is  the  method  employed,  but  it  also  occurs  to 
a  considerable  extent  even  in  roasting.  Some  of  the  salts  are  also 
dissolved  out  by  boiling,  and  reference  has  already  been  made  to  the 
fact  that  cooking  removes  some  fat  as  well.  These  general  effects 
of  cooking  are  illustrated  in  the  following  analyses  by  Konig  of  a 
piece  of  meat  before  and  after  cooking  i^ 

1  Adler,  Berlin  Klin.  Woch.,  1908,  xlv.  393. 

2  For  turther  information  on  this  subject,  see  '  Experiments  on  Losses  in 
Cooking  Meat,'  by  H.  S,  Grindley  and  Timothy  Mojonnier,  United  States 
Department  of  Agriculture,  Ofiice  of  Experiment  Statioas,  BulL  No.  14I, 
1904. 


DIGESTION  OF  MEAT 


65 


Water. 

Nitrogenous 
Matter. 

Fat. 

Extractives. 

Mineral 

Matter. 

Beef:  raw 

boiled 
roasted 
Veal  cutlets : 
raw . . 
roasted 

70-88 
56-82 
55  "39 

71-55 
57*59 

22-51 
34-13 
34-23 

20-24 
29-00 

4-52 
7-5" 
8-21 

6-38 
11-95 

0-86 
0-40 
072 

0-68 
0-03 

1-23 
I-15 

1-45 

I-I5 

1-43 

The  following  results  were  got  by  Tankard.^  They  represent  the 
composition  of  various  kinds  of  meat  cut  from  the  cold  roast  joint, 
and  wholly  edible.  They  include  such  a  proportion  of  fat  as  would 
be  commonly  helped  and  eaten  with  the  lean,  but  are  exclusive  of 
skin,  gravy,  and  dripping : 


Mutton. 

Lamb. 

Beef. 

Veal. 

Pork. 

Duck. 

FowL 

Water  (dried  at  100°  C.) 
Fat  (ether  ext.)  .. 
Protein  (N  x  63) 
Ash           

39-76 

26-80 

29-04 

1-93 

59-89 

11-95 

24-69 

1-63 

45-63 

24-21 

26-50 

I-2I 

51-88 

"•39 

32-19 

1*57 

44-90 

19-67 

32-63 

1-86 

64-13 
6-06 

27-12 
2-04 

67-40 
6-68 

24-26 
1-37 

97-53 

98-16 

97*55 

97*03 

99-06 

99*35 

9971 

=  45 


-7  5- 


34:/ 


67 


FAT. 


PROTEJNk 


WATER. 


raw.  boiled. 

Fig.  6.  —  Comparative 
Composition  of  Raw 
AND  Boiled  Beef. 


Taking  Konig's  figures,  the  composition 
of  raw  and  boiled  beef  may  be  graphically 
compared  as  in  Fig.  6. 

2.  Digestibility  and  Absorption  o» 
Meat. 

All  solid  foods  are  digested  in  the  stomach 
in  a  physical  sense ;  that  is  to  say,  they  are 
reduced  to  a  fluid  or  pulp,  in  which  condition 
alone  they  are  able  to  pass  on  into  the  in- 
testine. But  meat  is  a  food  the  main  share 
in  the  chemical  digestion  of  which  also  falls 
to  the  lot  of  the  stomach  ;  that  is  to  say,  its 
chief  nutritive  constituent  (protein)  is  there 
got  into  a  form  fit  for  absorption.  Now,  it 
may  be  laid  down  as  a  rule  that  the  greater 
the  extent  to  which  the  chemical  digestion  of 
a  food  goes  on  in  the  stomach,  the  easier 
does  its  mechanical  digestion  prove.  Hence, 
although  meat  makes  considerable  demands 
on  the  gastric  juice,  it  does  not  throw  any 
great  strain  on  the  mechanical  resources  oi 


*  Allen's  '  Commercial  Organic  Analysis,'  iv.  269,  second  edition,  1898. 


66  FOOD  AND  DIETETICS 

the  stomach,  and  for  that  reason  it  must  be  regarded  as  among  the 
more  easily  digested  of  the  solid  foods. 

The  first  change  which  takes  place  during  the  digestion  of  meat 
is  that  the  fibres  swell  up  and  become  softened ;  their  colour  then 
changes  to  a  grayish -yellow  ;  they  fall  apart,  arid  the  mass  becomes 
pulpy.  Last  of  all,  the  individual  fibres  split  up  either  into  longi- 
tudinal threads  or  transversely  into  discs.  It  will  be  evident  that 
the  ease  with  which  these  changes  can  occur  must  depend  on  many 
conditions.  The  harder  and  denser  the  connective  tissue  which 
holds  together  the  fibres,  the  less  readily  will  they  separate,  and  the 
greater  the  amount  of  fat  between  the  fibres,  the  less  readily  can  the 
gastric  juice  act  upon  the  latter,  hence  the  indigestibility  of  tough 
and  fat  meats.  The  longer  and  thicker  the  individual  fibres,  the 
more  slowly  are  they  split  up ;  hence  the  improvement  in  the 
digestibility  of  tough  meat  which  results  from  breaking  up  the  fibres 
by  pounding  the  meat  across  its  cut  ends.  The  influence  of  cooking 
also  is  of  great  importance.  It  has  been  found  by  experiments  on 
man^  that  3^  ounces  (a  small  helping)  of  beef  disappears  completely 
from  the  stomach  in  the  following  times,  depending  on  the  method 
by  which  it  has  been  cooked : 


Raw  .. 
Half  boiled  . . 
^Vholly  boiled 
Half  roasted 
Wholly  roasted 


2  hours. 

2i      .. 

3  M 

3  .. 

4  .. 


Artificial  experiments   outside  the  body  corroborate  these  results. 

Popoff2  found  that  the  proportions  digested  in  a  given  time  were  as 

follows : 

Raw  100  parts. 

Boiled        834  „ 

Smoked      . .  . .  . .  ji      „ 

Boiled  and  smoked         . .  606  „ 

Stutzer'  found  that,  of  100  parts,  there  is  dissolved  in  half  an  hour: 

Raw.  Boiled. 

By  weakly  acid  juice  . .         . .     89  2  per  cent.        38  7  per  cent. 
By  normal  juice  ..         ..     969        ,,  793 

Similar  experiments  by  Chittenden  and  Cummins*  confirm  these 
conclusions,  and  the  only  experiments  with  which  I  am  acquainted 
which  resulted  differently  were  some  by  UfiFelmann^  on  a  boy  with  a 
gastric  fistula;,  in  whom  it  was  found  that  raw  meat  was  digested 

'  Jessen,  Zdt.  fi'ir  Biologie,  1883,  xix.  129. 

2  Popofif,  Zeit.  filr  Physiol.  Chemie,  1890,  xiv.  52.]. 

*  Weyl's  '  Handbuch  der  Hygiene,"  Bd.  iii.,  p.  216 

*  American  Chemical  Journal,  1884-85,  vi.  31^ 
-  Deut.  Archiv,  fiir  Klin.  Med.,  1877,  xx.  535. 


DIGESTIBILITY  OF  MEAT  67 

rather  more  slowly  than  roast,  although  the  fibres  of  the  latter  fell 
apart  more  rapidly. 

On  the  whole,  one  may  conclude  that  most  forms  of  cooking  tend 
to  lessen  the  digestibility  of  meat  in  the  stomach,  a  conclusion  which 
applies,  almost  without  exception,  to  all  forms  of  animal  food,  but  is 
quite  the  reverse  of  true  as  regards  vegetable  foods  (see  Chapter  X.). 

In  accordance  with  these  experimental  results  one  finds  that  raw, 
or  at  all  events  much  underdone,  meat  is  a  form  of  food  which 
patients  with  very  weak  stomachs  can  digest  more  easily  than  most 
other  forms  of  nourishment.  The  best  method  of  preparing  such 
meat  is  by  scraping  a  piece  of  tender  juicy  steak  with  a  blunt 
instrument  in  a  direction  parallel  to  the  course  of  the  fibres.  This 
separates  out  the  fibres  from  the  enclosing  connective  tissue,  and 
leaves  the  latter  behind.  The  fibres  form  a  pulp  which  can  be 
seasoned  with  celery,  salt,  and  a  little  pepper,  and  served  either  as  a 
sandwich  or  stirred  into  broth.  In  what  is  known  as  the  Salisbury 
cure  another  method  of  administration  is  adopted.  The  meat  is 
chopped  very  thoroughly,  all  visible  connective  tissue  and  gristle 
being  removed,  and  it  is  then  made  into  little  cakes  ^  to  i  inch 
in  thickness,  and  of  3  or  4  inches  diameter.  These  are  placed 
in  a  clean  frying-pan,  strongly  heated,  but  without  either  water 
or  grease.  When  one  surface  of  the  cakes  is  seared  they  are 
turned  over  and  the  other  heated  similarly.  They  are  then  covered 
and  set  on  the  side  of  the  fire  till  the  red  colour  of  the  meat  has 
been  changed  to  a  drab.  They  are  finally  seasoned  with  a  little 
fresh  butter  and  salt,  and  are  ready  to  be  served. 

As  regards  the  relative  digestibility  of  the  different  kinds  of  meat, 
there  are  but  few  exact  data  available.  There  is  a  general  impression 
that  mutton  is  more  easily  digested  than  beef,  which  some  have 
attributed  to  the  finer  fibres  and  looser  connective  tissue  of  the 
former.  Jessen,  however,  found  that  3^  ounces  of  raw  mutton  were 
digested  in  precisely  the  same  time  as  an  equal  weight  of  beef; 
while  the  experiments  of  Chittenden  and  Cummins  showed  that  the 
digestibility  of  mutton,  outside  the  body  at  least,  was  inferior  to  that 
of  beef  (92  as  compared  to  100).  They  admit,  however,  that  the 
results  varied  greatly  in  different  samples  owing  to  age  and  other 
conditions.  There  can  be  no  doubt  that  mutton  fat,  especially 
when  hot,  is  particularly  apt  to  prove  irritating  to  the  stomachs  of 
some  persons,  and  in  them  the  eating  of  such  articles  as  mutton  pies 
or  Irish  stews  is  prone  to  be  followed  by  an  attack  of  acute  gastric 
catarrh. 

Veal  is  believed  to  be  somewhat  difficult  of  digestion,  a  belief 


68  FOOD  AND  DIETETICS 

which  is  confirmed  by  experiment,  for  it  required  two  and  a  half 
hours  for  its  digestion,  as  compared  with  two  hours  for  beef  (Jessen). 
The  difficulty  of  digesting  veal  is  somewhat  surprising,  for  the 
connective  tissue,  though  abundant,  is  very  easily  changed  into 
gelatin.  It  is  believed  by  some  that  the  explanation  is  to  be  found 
in  the  ease  with  which  the  fibres  of  veal  elude  the  teeth  on  mastica- 
tion; the  rather  insipid  taste  of  veal  may  also  be  a  contributive 
cause,  for  such  foods  do  not  tend  to  excite  a  free  flow  of  gastric 
juice. 

The  comparative  indigestibility  of  pork  is  shown  by  the  fact  that 
3^  oimces  of  it  required  three  hours  for  their  complete  digestion, 
as  compared  with  two  hours  for  beef.  The  difficulty  here  is  fully 
accounted  for  by  the  large  accumulation  of  fat  between  the  fibres. 
On  the  other  hand,  the  fat  of  bacon  seems  to  be  in  a  granular  form, 
which  is  not  difficult  to  digest,  and  it  can  often  be  eaten  with 
impunity  by  persons  to  whom  other  forms  of  fat  are  intolerable. 
For  this  reason  bacon  is  an  invaluable  aid  in  feeding  delicate 
children  and  diabetic  or  phthisical  patients  in  whose  diet  the  free 
use  of  fat  is  indicated. 

The  breast  of  chickens  and  game  is  amongst  the  most  digestible 
forms  of  meat,  but  the  leg  muscles  are  often  very  tough.  Very  fat 
poultry  should  be  avoided  by  the  dyspeptic,  as  the  fat  of  such  birds 
is  particularly  apt  to  become  rancid. 

Lastly,  it  must  be  pointed  out,  in  connection  with  the  relative 
digestibility  of  different  sorts  of  meat,  that  idiosyncrasy  plays  a 
very  large  part  in  the  process.  There  are  persons,  for  instance, 
whom  mutton  invariably  makes  ill,  while  they  can  eat  beef  with 
impunity,  and  others  who  can  take  mutton,  but  cannot  touch  beef. 
No  explanation  of  such  cases  can  be  given. 

The  absorption  of  meat  has  already  been  referred  to  (Plate  II.). 
It  was  shown  that  only  about  5  per  cent,  of  the  organic  matter  in 
meat  fails  to  enter  the  blood,  and  that  as  the  result  of  this  meat  is  a 
food  which  leaves  a  very  small  residue  in  the  intestine.  This  gives 
it  a  special  value  in  some  cases  of  intestinal  disease. 


3.  Nutritive  Value  and  Economy  of  Meat. 

The  principal  nutritive  constituent  of  meat  is  protein,  and  it  is  as 
a  compact  and  easily  digested  source  of  this  that  meat  is  chiefly  of 
value.    Meat  is  thus  one  of  the  best  sources  of  building  material  for 


DIGESTIBILITY  OF  MEAT  69 

the  body.  We  have  also  seen  that  protein  is  characterized  by  the 
rapidity  with  which  it  can  be  broken  down  by  the  cells  with  the 
liberation  of  heat,  or,  in  other  words,  that  it  is  a  *  quick  fuel.'  It  is 
to  this  fact,  probably,  that  meat  owes  the  '  heating '  qualities  com- 
monly ascribed  to  it,  and  for  a  similar  reason  its  use  should  be 
restricted  in  hot  weather.  The  use  which  is  made  of  meat  in 
training  has  been  justified  on  the  same  grounds  (p.  38).  Another 
characteristic  of  protein  is  that  it  seems  to  exert  a  stimulating  effect 
on  the  cells  and  on  the  body  generally,  and  the  feeling  of  well-being 
which  follows  a  meat  meal  may  be  put  down  to  this  cause.  In 
savages  who  are  unaccustomed  to  meat  the  free  consumption  of  it  is 
said  sometimes  to  produce  a  nervous  excitement  amounting  almost 
to  intoxication.  For  this  reason,  too,  the  presence  of  much  meat  in 
the  diet  seems  to  act  as  an  exciter  of  the  animal  passions,  and  an 
eminent  authority^  has  advised  that  in  the  treatment  of  cases  in 
which  such    propensities   require  to  be  kept  in  check  one  should 

*  avoid  flesh,  as  the  incarnation  of  rampant,  uncontrollable  force.' 

Meat  is  one  of  the  few  articles  of  diet  on  which  life  can  be 
supported  alone  for  an  almost  indefinite  time.  It  cannot,  however, 
be  regarded  as  constituting  in  itself  anything  like  a  perfect  food.  It 
is  relatively  much  too  rich  in  protein  and  too  poor  in  other  nutritive 
constituents.  It  would  require  about  4^  pounds  of  it  a  day  to  supply 
the  energy  required,  and  such  a  quantity  would  be  apt  to  damage 
the  digestion,  besides  overloading  the  blood  with  nitrogenous  waste 
products. 

The   almost   exclusive   use   of    lean   meat   is   the   basis   of    the 

*  Salisbury  cure,'*  to  which  reference  has  already  been  made,  and  it 
has  also  been  recommended  as  a  means  of  treating  some  diseases  of 
the  skin — e.g.,  psoriasis^ — which  have  resisted  the  ordinary  remedies. 
The  use  of  meat  in  such  diseases  as  diabetes,  gout,  and  obesity,  will 
be  dealt  with  in  another  chapter. 

The  relative  nutritive  value  of  different  sorts  of  meat  depends 
chiefly  on  the  amount  of  fat  they  contain.  Fat,  as  we  have  seen, 
replaces  part  of  the  water,  and  not  the  protein,  of  the  leaner  meats, 
and  thus  the  fat  meats  are  better  sources  of  fuel  than  the  latter, 
while  not  inferior  to  them  in  building  material.  Apart  from  this,  the 
nature  of  the  extractives  present  may  perhaps  have  some  influence 
on  general  metabolism.     Dr.  Smith*  tells  us  that  Kean,  the  famous 

^  Clouston,  'Insanity,'  p.  520.  See  also  Mr.  Eustace  H.  Miles's  'Better  Food 
for  Boys  '  (London:  George  Bell  and  Sons,  1901). 

*  'The  Relation  of  Alimentation  and  Disease';  Salisbury,  New  York,  1S95. 

•  Parkes,  Lancet,  1874,  i.,  p.  722.  *  Food,  p.  52. 


70  FOOD  AND  DIETETICS 

actor,  used  to  adapt  the  kind  of  meat  he  ate  to  the  part  he  had  to 
play,  choosing  pork  for  tyrants,  beef  for  murderers,  and  mutton  for 
lovers.  This  may  seem  far-fetched,  but  it  may  indicate  that  there 
are  subtle  differences  in  the  different  kinds  of  meat  which  chemistry 
does  not  enable  us  to  detect,  but  which  are  yet  not  without  influence 
upon  the  body. 

From  an  economic  point  of  view  meat  is  a  dear  food.  This 
is  clearly  shown  in  Plate  III.,  and  holds  good  whether  one 
regards  meat  merely  as  a  yielder  of  energy  or  as  a  source  of  build- 
ing material. 

The  costliness  of  it,  however,  can  be  considerably  diminished  by 
selecting  the  cheaper  •  cuts,'  which  are  equal  in  nutritive  value  to 
the  dearer  kinds,  though  inferior  in  tenderness  and  flavour.  The 
question  of  waste  from  bone,  etc.,  must  also  be  considered.  Thus, 
in  the  case  of  mutton  and  pork,  the  leg  contains  relatively  less  bone 
than  the  shoulder,  and  in  beef  there  is  a  much  larger  proportion  of 
bone  in  the  shin  than  in  the  round,  and  of  these  the  least  bony  parts 
will  be  the  most  economical  from  a  nutritive  point  of  view.  Much, 
too,  can  be  done  to  diminish  the  cost  by  the  use  of  the  cheap  frozen 
meats  which  are  now  imported.  These  are  equal  in  nutritive  value 
to  fresh  meat,  and  are  only  slightly  inferior  to  the  latter  in  keeping 
qualities.  They  are  not  drier  than  ordinary  meats,  as  is  often  stated, 
for  chemical  analysis  shows  that  the  proportion  of  water  is  only 
ID  per  cent,  less  than  that  of  fresh  meat,  while  their  digestibility  is 
precisely  the  same.^  From  an  economic  point  of  view,  also,  it  must 
be  regretted  that  there  exists  a  prejudice  against  the  use  of  horse- 
flesli  as  a  substitute  for  ordinary  meat.  It  is  well  flavoured — indeed, 
a  Chateaubriand  steak  is  said  by  connoisseurs  to  be  best  when  made 
of  horseflesh — and  any  toughness  can  be  overcome  by  suitable 
cooking.  In  Paris  the  use  of  horseflesh  for  human  food  is  increasing 
every  year,  and  one  can  only  hope  the  poorer  classes  in  this  country 
may  ultimately  take  to  it  too.  Indeed,  it  is  stated  to  be  already 
largely  used  in  the  manufacture  of  smoked  meats. 

There  is  also  a  prejudice  against  the  use  as  human  food  of  the 
flesh  of  animals  which  have  died  of  disease.  This,  again,  can  hardly 
be  justified  on  grounds  either  of  science  or  experience.  The 
shepherds  of  Scotland  have  long  used  '  braxy '  mutton — i.e.,  the 
flesh  of  sheep  which  have  died  of  various  diseases — and  I  am 
not  aware  that  it  has  ever  been  known  to  produce  any  harmful 

»  Gautier,  '  Frozen  Meat  as  an  Article  of  Diet '  (abstract  in  Edinburgh  Mtiicai 
Journal,  1897,  N.S.,  ii.  200). 


COST  OF  MEAT 


72 


results.  A  French  observer^  has  put  the  matter  to  the  test  of 
experiment.  He  took  the  flesh  of  animals  which  had  died  of 
various  diseases  (including  that  of  the  mad  dog !),  cooked  it  in 
various  ways,  and  gave  ft  to  people  who  were  ignorant  both  of  its 
nature  and  source.  No  bad  effects  followed  its  consumption.  He 
concludes,  fairly  enough,  that  the  use  of  diseased  meat  is  harmless 
provided  it  be  properly  cooked,  and  that  the  overstrict  inspection  of 
slaughter-houses  may  do  more  harm  by  rendering  meat  dear,  and 
therefore  inaccessible  to  the  poor,  than  it  does  good  by  preventing 
disease. 

It  should  be  remembered  that  all  small  animals,  such  as  rabbits, 
are  necessarily  expensive  forms  of  meat  both  on  account  of  their 
active  metabolism,  which  implies  that  the  greater  part  of  the  food 
they  eat  is  lost  in  the  form  of  heat,  and  also  because  of  the 
relatively  large  bulk  of  their  viscera.  It  is  therefore  impossible  to 
hope  that  they  can  ever  be  a  suitable  form  of  animal  food  for  the 
poorer  classes. 

There  remain  to  be  dealt  with  some  parts  of  animals,  other  than 
the  flesh,  which  are  sometimes  used  for  foods,  and  which  are  usually 
classed  together  under  the  somewhat  unsavoury  title  of  offal.  These 
comprise  such  articles  as  the  kidneys,  liver,  sweetbreads,  blood, 
heart,  lungs,  and  other  internal  organs,  and  together  make  up  about 
one-third  of  the  total  weight  of  the  carcase. 

The  general  composition  of  these  articles  is  shown  in  the  following 
table : 

COMPOSITION  OF  OFFAL. 


Water. 

Nitrogenous 
Matter.  2 

Fat. 

Carbo- 
hydrates. 

Ash. 

Kidney  (ox)             . 

767 

i6"9 

4-8 

0-4 

I '2 

(sheep)       . 

787 

i6-8 

3-2 

— 

I '3 

Liver  (ox)    . .         , 

71-2 

207 

4*5 

1-5 

1-6 

(sheep 

6i-2 

23-1 

9-0 

5'o 

17 

Heart  (ox)    . . 

62-6 

i6*o 

20 '4 

— 

I'O 

,,       (sheep)         . 

69-5 

17-0 

I2'6 

— 

0-9 

Lung  (ox)    . . 

797 

i6-i 

3*2 

— 

i*o 

,,      (sheep) 

75-9 

20 -2 

2-8 

— 

1'2 

Sweetbreads 

70-9 

i6-8 

I2-I 

— 

1-6 

Blood 

80 -8 

i8-i 

0-2 

— 

0-85 

Tripe 

74-6 

i6*4 

8-5 

— 

0-5 

Tongue  (ox)  fresh  . 

63-8 

17-1 

i8-i 

— 

i*o 

,,        smoked  and  salted 

357 

24*3 

31-6 

— 

8-5 

Brain           

80 -6 

8-8 

9-3 

— 

1*1 

1  Decroix,  '  Recherches  Experiraentales   sur  la  Viande  de  Cheval  et  sur  les 
Viandes  Insalubres ' ;  Paris,  1885. 

2  Nx6-25. 


72  FOOD  AND  DIETETICS 

It  will  be  observed  that,  from  the  chemical  point  of  view,  they  are 
substances  of  considerable  nutritive  value,  and  as  their  price  is  also 
for  the  most  part  low,  as  compared  with  that  of  ordinary  meat,  they 
must  be  regarded  as  important  sources  of  protein  in  the  diet. 

The  liver  and  kidnes^s  resemble  one  another  in  being  compact, 
solid  organs,  containing  but  little  connective  tissue.  This  physical 
property  renders  them  somewhat  difficult  of  digestion,  unless  they 
have  either  been  minced  before  cooking  (as  the  liver  is,  for  instance, 
in  making  a  haggis),  or  are  rather  carefully  chewed.  Chemically, 
both  consist  chiefly  of  protein  along  with  a  small  amount  of  fat. 
The  protein  which  they  contain  is  quite  different  from  that  of 
ordinary  meat,  consisting  as  it  does  to  a  large  extent  of  nucleo- 
protein,  which  yields  nuclein  on  digestion.  Now,  nuclein  is  an 
important  source  of  uric  acid,  and  for  that  reason  it  may  be  well 
for  gouty  persons  to  avoid  the  dietetic  use  of  the  articles  under 
consideration. 

The  heart  resembles  ordinary  meat  very  closely  as  far  as  chemical 
composition  is  concerned,  but  differs  from  it  in  being  of  a  denser 
structure,  and  therefore  less  digestible.  For  healthy  persons,  how- 
ever, it  is  an  excellent  and  economical  food,  and  might  with  advantage 
be  made  larger  use  of  than  it  is  at  present. 

It  seems  natural  to  suppose  that  blood  must  be  a  very  valuable 
food.  *  The  blood  is  the  life,'  and  it  would  seem  as  if  blood  must 
represent  in  itself  the  essence  of  strength  and  energy.  But  it  is  not 
so  ;  and  the  misconception  proceeds  from  a  neglect  of  the  fact  that 
blood  is  not  in  itself  the  food  of  the  tissues,  but  is  merely  the  vehicle 
by  means  of  which  nourishment  is  carried  from  the  intestines  to  the 
places  where  it  is  wanted  in  the  body.  One  might  as  well  expect  a 
spoon  to  be  of  nutritive  value  because  it  conveys  food  from  the  plate 
to  the  mouth.  Two  French  experimenters^  found  that  blood  when 
administered  to  dogs,  even  in  the  liberal  measure  of  2  pounds  daily, 
did  not  suffice  to  maintain  the  life  of  the  animals  for  more  than  a 
month.  This  is  due  in  part  to  the  fact  that  blood  is  a  dilute  fluid, 
for,  of  every  loo  parts  of  it,  from  78  to  82  consist  of  water.  Blood, 
in  fact,  from  a  chemical  point  of  view,  is  not  so  much  thicker  than 
water  after  all.  In  the  solids  there  is  plenty  of  protein,  but  the 
other  nutritive  constituents  of  food — fat  and  carbohydrates — are 
only  represented  in  quite  inappreciable  amount.  In  addition  to  this, 
the  red  colouring  matter  (haemoglobin)  which  makes  up  the  larger 
part  of  the  protein  is  a  substance  which  is  very  far  from  being 

*  Payea  and  Magendie. 


BLOOD  AS  FOOD  73 

completely  absorbed.^  There  are,  thus,  no  chemical  considerations 
which  can  outweigh  the  natural  repugnance  which  most  persons  feel 
to  the  eating  of  blood ;  and  though  it  may  be  used  without  harm,  if 
also  without  much  benefit,  in  the  form  of  black-puddings  and  such- 
like, there  is  no  reason  to  advocate  its  habitual  consumption,  much 
less  its  employment  in  the  feeding  of  the  sick ;  and  this  is  true  also 
of  the  use  of  blood  as  a  source  of  iron.* 

The  lungs,  from  the  fact  that  the  air  which  they  contain  enables 
them  to  float  in  water,  are  popularly  spoken  of  as  the  '  lights.' 
They  are  sometimes  eaten,  but  cannot  be  regarded  as  a  really  good 
form  of  food.  Their  chemical  composition  furnishes  the  reason. 
The  lungs  are  largely  composed  of  an  elastic  material  belonging  to 
the  group  of  albuminoids,  and  only  imperfectly  capable  of  digestion, 
besides  being  useless  as  building  matter  in  the  body. 

Under  the  term  sweetbread  butchers  include  at  least  two  distinct 
organs.  The  '  throat  sweetbread  *  is  known  to  anatomists  as  the 
thymus  gland ;  the  *  stomach  sweetbread '  is  the  pancreas.  The 
thymus  of  the  calf  is  the  one  most  frequently  met  with  in  the 
market.  Both  glands  are  cellular  organs,  held  together  by  a  loose 
and  delicate  connective  tissue.  From  the  nature  of  the  latter  they 
are  easily  dissolved  in  the  stomach,  and  rank  amongst  the  most 
digestible  of  animal  foods,  9  ounces  of  sweetbread  being  completely 
disposed  of  by  a  healthy  stomach  in  two  and  three-quarter  hours, 
while  a  similar  weight  of  beefsteak  demands  at  least  four  and  a  half 
hours  for  its  complete  digestion.^  The  cells  of  these  organs  are 
chiefly  composed  of  nucleo-protein,  and  for  that  reason,  as  has 
already  been  pointed  out  in  the  case  of  the  liver  and  kidney,  sweet- 
breads may  prove  harmful  in  some  cases  of  gout. 

Tripe  is  the  name  applied  to  the  stomach  and  intestines  of  the 
ox  after  being  cleaned  and  boiled.  It  contains  a  large  amount  of 
connective  tissue,  readily  changed  into  gelatin  on  boiling,  and  so 
rendering  the  fibres  easily  digested.  It  contains  fat  in  considerable 
amount,  but  not  diff'used  through  the  muscular  part.  I  am  not 
acquainted  with  any  experiments  on  its  rate  of  digestion  in  the 
stomach,  but  in  the  intestine  it  has  been  found  to  be  as  completely 

^  See  Gherardini,  Rev.  des  Sciencm  Med.,  1892,  xxxix.  88;  and  Robert,  St. 
Petersburger  Med.  Wochenschri/t,  1891,  p.  439.  Halliburton  has  investigated  (Brit. 
Med.  Journ.,  1904,  i.  823)  the  digestibility  and  absorption  of  haemoglobin.  He 
found  that  it  is  to  some  extent  at  least  digested  by  the  pancreatic  juice,  and 
experiments  on  rats  showed  that  ander  its  administration  the  number  of  red  cells 
in  the  blood  rises,  whilst  the  amount  of  iron  in  the  tissues  ii  increased. 

*  SeeStarck,  Deut.  Med.  Woch.,  1898,  xxiv.  805. 

•  Penzoldt,  Deut.  Archiv  Jur  Klin.  Med.,  1893,  U.  53^ 


74  FOOD  AND  DIETETICS 

absorbed  as  beef.i  Unfortunately,  the  absence  of  extractives  causes 
tripe  to  be  rather  deficient  in  flavour,  but  otherwise  it  must  be 
regarded  as  a  valuable  and  easily-digested  food. 

The  brain  of  animals  is  only  occasionally  eaten  as  food.  Brain 
consists  largely  of  a  fatty  material  containing  cholesterol  and 
lecithin,  the  latter  being  comparatively  rich  in  phosphorus.  In  the 
stomach,  owing  to  its  soft  consistency,  brain  is  more  rapidly  digested 
than  any  other  animal  food,  but,  unfortunately,  it  is  very  imperfectly 
absorbed,  43  per  cent,  of  it  reappearing  in  the  faeces  {vide  infra).  In 
spite,  therefore,  of  its  easy  digestion,  it  cannot  be  regarded  as  a 
valuable  food  for  invalids,  nor  is  it  in  any  sense  specially  apt  to 
*  make  brains.'  *  Some  fancy,'  says  an  ancient  writer,^ '  that  Rabbits' 
Brains  weaken  the  Memory,  because  this  animal  cannot  for  a  moment 
after  retain  in  mind  the  Foils  laid  for  her  and  that  she  had  just 
escaped ;  but  this  conjecture,  being  grounded  upon  a  weak  Founda- 
tion, I  shall  not  stop  here  and  go  about  to  confute  it.'  The  idea 
that  brain  can  in  any  way  contribute  to  the  nourishment  of  brain  is 
grounded  on  an  equally  '  weak  foundation.' 

The  comparative  absorption  of  some  of  the  articles  of  which  we 
have  been  speaking,  as  found  by  experiment,  is  as  follows ; 

Voit^  states  that 

100  parts  of  dry  liver  yield  5  parts  of  dry  faecea. 
..     lung  ,,     8 

,,        ,,     thymus       ,,7        ,,  ,, 

,,        ,,     brain  ,,   43        ,,  ,, 

Emil  Bergeat^  found  the  loss  of  nitrogen  in  the  dog  to  be : 

In  meat  2*1  per  cent. 

In  thymus 32        „ 

In  liver  3-3        „ 

In  lung  ..         ..         . .  4-2        ,, 

In  brain  ..         ..         . .  13*9        „ 

The  average  composition  of  some  potted  meats  is  represented  in 
the  following  table  (from  Konig) : 


Water. 

Nitrogenous 
Matter. 

N-free 
Extractives. 

Fat. 

Ash. 

Salt. 

Foie  gras 
Potted  beef      . . 

„      ham      . . 

„      tongue  .. 

4604 

32-81 
25:57 
4152 

14-59 
1717 
1688 
18-46 

2  67 
046 

3359 
4463 
5088 
3285 

3" 

2  03 
678 
671 

0  22 

572 
598 

'  Solomin,  Arch,  fur  Hygiene,  1996,  xxvii.  176, 
2  Lemery,  1745. 

*  Zeit.  fur  Biologie,  i88g,  xxv.  232. 

*  Ibid.,  1888,  xxiv.  120. 


POTTED  MEATS  AND  SAUSAGES 


75 


These  substances  require  no  special  description. 

Sausages  are  preparations  of  very  uncertain  composition.  It  ha.u 
been  remarked  of  them  with  some  truth  that  they  are  like  life ;  for 
you  never  know  what  is  in  them  till  you  have  been  through  them. 
In  this  country  they  are  usually  made  of  uncooked  meat,  but  various 
vegetable  substances,  especially  bread,  are  frequently  added  as  well, 
and  the  vegetable  matter  is  not  infrequently  disguised  by  the  addition 
of  colouring  materials.  Seasonings  of  various  sorts  also  enter  into 
their  composition,  and  most  of  them  contain  a  boron  preservative. 
The  following  analyses  by  Allen  ^  represent  the  composition  of  some 
typical  kinds : 

COMPOSITION  OF   SAUSAGES. 


Variety. 

Price  per  lb. 

Water. 

Fat. 

Proteiu. 

Gristle,  etc 

Starch. 

Pork  . . 

9d. 

5499 

2104 

1228 

067 

105 

'  Cambridge ' 

pork 

9d. 

5154 

2972 

945 

0-72 

2-20 

Mutton 

IS. 

5558 

3051 

1-89 

311 

390 

German        .. 

8d. 

4654 

17-87 

16-38 

I  13 

15  00 

Polony 

lod. 

4557 

3266 

17  26 

0-54 

2-30 

Ash. 


352 

347 
2-50 

447 
2-80 


As  sources  of  protein,  they  are  certainly  not  more  economical  than 
ordinary  meat. 

The  use  of  bones  as  food  will  be  dealt  with  in  the  next  chapter. 


I  •  Commercial  Organic  Analysis,'  second  edition,  vol.  iv.,  p.  280. 


i    7b   j 


CHAPTER  V 
JELLIES— FISH 

The  chemical  basis  of  jellies  is  gelatin.     Gelatin  is  derived  from 

collagen,  which  is  the  chief  constituent  of  connective  tissues,  and  is 
converted  into  gelatin  by  boiling.  All  forms  of  connective  tissue 
can  be  made  to  yield  gelatin  by  suitable  treatment.  Glue  is  a  crude 
form  of  the  substance  obtained  from  hide-clippings,  and  ordinary 
commercial  gelatin  is  simply  a  purified  form  derived  from  the  same 
source.  The  connective  tissues  of  young  animals  are  especially  rich 
in  gelatin-yielding  material.  Veal,  for  example,  contains  4  to  5  per 
cent,  of  connective  tissue,  and  is  tlierefore  a  favourite  basis  for  the 
making  of  strong  soups.  Calves'  feet  (free  from  bone)  yield  25  per 
cent,  of  gelatin  on  boiling  and  11-3  per  cent,  of  fat,i  and  have  long 
been  known  as  abundant  yielders  of  a  pure  jelly.  The  purest  form 
of  all,  however,  is  isinglass,  a  substance  obtained  from  the  swim- 
bladder  of  fish,  especially  of  the  sturgeon.  Chemically  it  is  not 
really  richer  than  ordinary  gelatin,  as  is  shown  in  the  following  com- 
parative analyses  :^ 

Ordinary  Gelatin.  Isinglass. 

Water  136  190 

Albuminoid.,         ..         ..  842  77'4 

Fat 01  i"6 

Carbohydrate         ..         .. 

Ash 21  2*o 

Full  value  per  pound        ..     1,570  Calories.       1,510  Calories. 

The  chief  physical  peculiarity  of  gelatin  is  its  capability  of  dis- 
solving in  boiling  water,  and  setting  into  a  jelly  on  cooling.  It 
is  remarkable  how^  weak  a  solution  is  capable  of  doing  this.  Even 
when  as  little  as  i  per  cent,  is  present  the  solution  sets.  The  ordinary 
strength  of  which  jellies  are  made  is  i  ounce  of  gelatin  to  the 
quart,  which  is  equivalent  to  a  2  per  cent,  solution,  and  from  this 
one  can  realize  how  little  gelatin  there  really  is  in  ordinary  jellies. 

^  Uffelmann,  'Ueber  Sparstoflfe  und  deren  Verwendung  in  der  Kost  der  gesun- 
den  und  Kranken,'  Wiener  Klinih,   1S91,  xvii.,  Heft  7. 

-  Atwater,  '  Chemical  Composition  of  American  Food  Materials,'  Bulletin  28, 
United  States  Department  of  Agriculture. 


GELATIN  77 

I  have  found  that  6  ounces  (a  large  helping)  of  ordinary  calfs- 
foot  jelly  contains  i§  ounces  of  solid  matter,  of  which  less  than 
^  ounce  is  gelatin,  the  remainder  being  chiefly  sugar. 

The  digestion  of  gelatin  in  the  stomach  is  a  very  easy  process ; 
indeed,  in  this  respect  it  is  hardly  surpassed  by  any  other  food. 
Uffelmann  found  that,  in  a  boy  with  a  gastric  fistula,  complete 
peptonisation  took  place  within  an  hour,  but  he  does  not  state  how 
much  jelly  was  administered. 

Gelatin  has  the  advantage  of  fixing  a  good  deal  of  acid  in  the 
process  of  digestion,  and  is  thus  of  service  in  cases  of  hypersecre- 
tion of  acid  in  the  stomach.  It  seems  also  to  belong  to  the  *  pepto- 
genic'  substances — i.e.,  those  bodies  which  favour  an  abundant  flow 
of  gastric  juice  (see  p.  417). 

In  estimating  the  nutritive  value  of  gelatin,^  it  is  important  to 
emphasise  again  that  gelatin  is  not  capable  of  building  tissues, 
and  is  in  no  sense  a  true  substitute  for  proteins.  This  is  due  to 
the  fact  that  some  of  the  amino-bodies — e.g.,  tryptophans — which 
are  essential  for  the  building  up  of  human  protein,  are  not  con- 
tained in  it.  As  a  source  of  heat  and  energy,  it  is  equal  to  protein 
or  carbohydrate,  i  gramme  yielding  about  4"i  Calorie& 

It  is  as  a  sparer  of  protein,  however,  that  gelatin  is  chiefly  of 
importance  in  the  food.  It  is  the  most  powerful  protein-sparer 
known,  being  able  to  save  from  destruction  half  its  weight  of 
protein,  or  twice  as  much  as  is  spared  by  an  equal  quantity  of  carbo- 
hydrate ;  but  in  estimating  its  value  in  this  direction  as  an  ordinary 
food,  it  must  be  remembered  that  even  those  who  live  on  a  mainly 
animal  diet  do  not  consume  more  than  one-tenth  to  one-eighth  of 
their  total  nitrogen  in  the  form  of  gelatin,  and  that  probably  not  more 
than  25  to  30  grammes  (about  i  ounce)  of  the  latter  substance  can 
conveniently  be  taken  in  a  day.  This  restricts  its  usefulness  con- 
siderably, for  even  a  quart  of  jelly  would  only  be  able  to  spare  the 
protein  in  2 J  ounces  of  meat ;  and  assuming  that  25  grammes  of 
gelatin  were  contained  in  the  diet,  this  would  only  efiect  a  saving  of 
35  grammes  of  meat  (i^  ounces)  and  40  grammes  of  bread  (i^  ounces). 
An  ordinary  slice  of  a  4-pound  loaf  weighs  2|-  ounces.  One  can 
realize  from  this  that  the  usefulness  of  gelatin  as  a  protein-sparer 
in  fevers  and  diabetes  is  of  limited  range.  As  a  pleasant  addition  to 
the  diet  of  convalescence,  however,  jellies  are  of  service,  but  their 
nutritive  value  depends  mainly  on  the  sugar  which  they  contain,  and 

1  See  Murlin,  Amcr.  Journ.  of  Physiol.,  1907,  xix.  285;  and  Mancini,  7i  Poli- 
clinico,  igo6,  xiii.,  Sez  Prat.  173  (abstract  in  Archiv  /.  Verdauungshrank.,  1907, 
xiii.  326). 


78  FOOD  AND  DIETETICS 

not  on  the  gelatin.     Their  value  in  acid  dyspepsia  has  already  been 
mentioned. 

The  cost  of  gelatin  depends  entirely  on  the  source  from  which 
it  is  derived,  and  for  ordinary  purposes  commercial  gelatin  is 
the  most  economical.  It  has  been  calculated  that  it  costs  six- 
teen times  as  much  to  prepare  jelly  from  calves'  feet  as  to  use 
commercial  gelatin  for  the  purpose  (Thudichum).  Isinglass  is 
also  a  costly  source,  a  quart  of  jelly  made  of  commercial  gelatin 
costing  about  6d.,  whereas  if  isinglass  be  used  it  will  cost  about 
IS.  gd.,  and  it  does  not  even  seem  to  be  altogether  true  that 
the  latter  goes  further  and  sets  better.  The  same  is  true  of  soups, 
for  it  is  cheaper  to  add  7  or  10  grammes  (^  to  J  ounce)  of  gelatin  to 
ordinary  stock  if  one  wants  a  strong  soup  than  to  get  the  gelatin 
from  boiling  up  veal.  Bones  are  only  a  cheap  source  of  it  in  so 
far  as  they  cannot  be  used  for  any  other  purpose.  The  composition 
of  bones  is  about  as  follows  : 

Water  . .  . .  . .       5  to  50  per  cent. 

Gelatin  substance  . .  ..  151050        ,, 

Fat    ..  ..  ..  ..       ^  to  20         ,, 

Ash   ..         ..         ..  ..  20  to  70        ,, 

When  boiled  in  the  usual  way  they  yield  from  li  to  7  per  cent,  of 
their  weight,  chiefly  in  the  form  of  fat.  When  broken  up  and 
treated  in  a  Papin's  digester  the  yield  is  greater,  3  pounds  yield- 
ing (according  to  Smith)  as  much  nitrogen  as  can  be  got  from 
7  pounds  of  meat,  and  as  much  carbon  as  is  yielded  by  i  pound 
under  similar  treatment.  In  spite  of  this,  Forster  concluded  from  his 
experiments  on  the  subject  that  it  is  cheaper  to  use  commercial 
gelatin  than  to  buy  bones  specially  to  produce  it.  Gelatin,  there- 
fore, is  merely  a  cheap  addition  to  poor  diets  in  so  far  as  it  can  be 
obtained  from  many  materials  which  would  otherwise  be  wasted,  and 
ordinary  jellies  can  only  be  regarded  as  dear  foods,  for  a  shilling 
spent  on  the  '  calf 's-foot  jelly  *  of  the  shops  yields  only  47c  Calories 
of  energy,  and  no  building  material  at  all. 

FiSH.l 

I.  Chemical  Composition. — Protein  and  fat  are  the  chief  nutritive 
constituents  found  in  fish,  just  as  they  are  in  meat.     According  to 

^  In  preparing  this  section  the  writer  has  derived  much  help  from  the  following 
publications  :  '  The  Chemical  Composition  and  Nutritive  Values  of  Food  Fishes 
and  Aquatic  Vertebrates,'  by  W.  O.  Atwater,  Ph.D.,  Washington,  1891  (abstract 
from  Report  of  United  States  Commissioner  of  Fish  and  Fisheries,  1888) ;  and 
'  Fish  as  Food,'  United  States  Department  of  Agriculture,  Faroxers'  Bulletin  85, 
1898.  by  C.  F.  Langworthy,  Ph.D. 


COMPOSITION  OF  FISH 


79 


the  relative  proportions  of  these  ingredients  present,  fish  may  be 
conveniently  divided  into  the  two  groups  of  'fat'  and  'lean,'  or, 
more  exactly,  thus : 

(a)  Fish  with  more  than  5  per  cent,  of  fat. 

Examples:    Eel    (18   per   cent.),    salmon    (12   per    cent.),    turbot 
(12  per  cent.),  herring  (8  per  cent ). 
{b)  Fish  with  from  2  to  5  per  cent,  of  fat. 

E.xamples  :  Halibut  (2  up  to  even  10  per  cent.),  mackerel  (2  up  to 
9  per  cent),  mullet  (about  2^  per  cent.). 
(c)  Fish  with  less  than  2  per  cent,  of  fat. 
Examples  :  Cod,  haddock,  whiting. 

The  exact  chemical  composition  of  the  commoner  varieties  of  fish 
is  shown  in  the  following  analyses  by  Wiss  Katherine  Williams,^  the 
results  having  reference  to  the  fish  as  prepared  for  the  table : 

ANALYSIS  OF  COOKED  (BOILED)  FISH  AS  SERVED  AT  TABLE. 


Fish. 


Herring 

Salt  herring 

Sprats 

Salmon 

Salmon  peal 

Trout 

Smelts 

Californ'a  salmon 

Eels 

Red  mullet 

Roach 

Gurnet       . . 

Mackerel   . . 

Cod 

Salt  cod     . . 

Haddock    .. 

Hake 

Whiting     .. 

Turbot 

Brill 

Halibut      .. 

Plaice 

Soles 

Lemon  soles 

John  Dory 


89 


Protein. 


26-46 

20-93 

19-64 

24 '59 
21-13 

I5"9i 
21-54 
16-68 

21  "02 
19-49 
23-38 
16-74 
21-67 
21-03 
21-98 
12-30 

I6-SS 
iS-77 
3i'oo 
20-34 

i5'^3 
18-03 
15-29 
17-54 


Fat,  or 
Ether  Extract, 


Ash. 


9-96 
11-28 

6-63 
I0-20 
25-97 

2  33 
I -08 

13-05 

17-33 

7-78 

3-70 
0-47 
6-91 
0-27 
0-26 
0-3G 
0-87 
0-39 
1-05 
064 
4-04 
1-98 
0-35 

0-45 


2-21 

11-28 
1-56 
I  -72 
2-15 

1-74 
0-91 
2-i6 
6-82 
1-72 
0-26 

0-93 
1-09 
0-76 

3-94 
0-91 

0-57 
0-41 
0-51 
1-65 
1-05 
082 

0-57 
0-97 
0-19 


*  Chemical  News,  1911,  vol.  civ.,  p.  271. 


8o 


FOOD  AND  DIETETICS 
ANALYSIS  OF  FLESH  OF  COOKED  FISH. 


Reducing 

Solids 

N  Dry  Substanck. 

Fish. 

Water  in 

Flesh 

Substances 

in  Dry  Matter 

as  Glucose. 

Ash  in  Dry 

-j^ 

N. 

Fat. 

Protein. 

Herrings  . . 

60-54 

— 

5-56 

II'II 

25*25 

67*07 

Salt  herrings 

46-03 

17*59 

19-69 

7-12 

21*90 

38*88 

Sprats 

7577 

9-88 

6*42 

9-26 

27*37 

57*94 

Sardines  . .         . . 

44*35 

— 

12-03 

8*54 

33*49 

55*44 

Salmon    . . 

65-32 

14*89 

4*94 

10-70 

29*43 

56-65 

Trout 

73-58 

4-68 

6-60 

1 1 '96 

8*84 

80 -oo 

Eels 

61 -08 

8-91 

2*11 

■    7*36 

44-68 

42*88 

Mackerel . . 

73-13 

13-93 

4*07 

1 0*46 

2573 

62*32 

Cod 

76-32 

6-67 

3*31 

15*30 

1*15 

91-55 

Salt  cod  .. 

72-35 

7-14 

14-26 

12-41 

0-94 

76-06 

Haddock  . . 

72-37 

13*15 

3-28 

13*11 

1*29 

79-57 

Whiting  . .          , , 

78-78 

17*54 

1-92 

13*28 

1*86 

79*55 

Turbot     .. 

77-84 

ii-8i 

2-41 

1376 

4*75 

8471 

Halibut   .. 

74-46 

— 

4-II 

13*32 

15*81 

79*67 

Plaice 

77-86 

11-56 

4-06 

13*02 

9*84 

75-16 

Soles 

79-20 

11-87 

3-47 

14*00 

1*71 

86-71 

Lemon  soles 

78-11 

14-80 

4*42 

11*04 

12*96 

69*88 

Oysters    . . 

77-71 

18-32 

I2-l6 

11-85 

7*77 

65-42 

Smelts      ..          ,. 

80-73 

2-17 

4*73 

1 1 -61 

9-76 

82-59 

Red  mullet         ,, 

68-26 

9-79 

5-43 

11-59 

24*52 

66-26 

Roach      . .         , , 

75-37 

6-2S 

I -08 

13*03 

15-03 

79-14 

Gurnet     . . 

73-77 

14*77 

3*53 

14-24 

I -81 

89-16 

Tunny      . .         , . 

63-49 

5*52 

10-55 

30*68 

66-08 

Hake 

84-88 

13-64 

3-90 

12*86 

5-67 

81*36 

ohn  Dory 
Brill 

77-89 

14-29 

2 -06 

13*32 

8-52 

79-53 

62-74 

— 

4-42 

15*49 

1*62 

93*95 

In  the  following  table  the  composition  of  some  of  the  commoner 
varieties  of  fish  in  the  fresh  state  is  represented  in  a  more  con- 
venient form  than  in  the  above  : 

COMPOSITION  OF  FISH.» 


Cod 

Eel 

Flounder . . 
Haddock .. 
Halibut  .. 
Herring  . . 
Mackerel 
Mullet  . . 
Salmon  . . 
Smelt 
Trout  (river) 

,,      (salmon) 
Turbot     . . 


Water. 


82-6 
71*6 
84-2 
81-7 
75-4 
72*5 

73*4 
74*9 
64-6 
79-2 

77-8 
70-8 
71*4 


Protein 


165 
i8-6 
14-2 
17-2 
186 

195 
187 

19-5 
22  o 
17-6 
19-2 

178 
14-8 


Fat 


0-4 
9*1 

o*6 
0*3 

5-2 

7-1 
7'i 
4-6 
12-8 
1*8 

2*1 

10-3 

14-4 


Aah. 


1*2 

10 
1-3 


1-5 


1-4 
17 
12 
12 
1-3 


Fuel  Value 

per  Pound  in 

Calories, 


325 
730 
290 

335 
565 
660 

645 

555 
950 
405 
445 
765 


1  Compiled  from  analyses  in  the  '  Chemical  Composition  of  American  Food 
Materials,'  by  Atwater  and  Bryant,  Bull.  No.  28  (revised  edition),  U.S.  Depart- 
ment of  Agriculture,  Office  of  Experiment  Stations,  1899. 


COMPOSITION  OF  FISH  8l 

To  these  may  be  added  some  recent  analyses  of  preserved  fish 
and  of  sardines  in  oil : 

PRESERVED  FISH. 

Water.  Nitrogenous  Matter.  Fat.  Ash.         Salt. 

Dried  cod         ..         i6-i6                81-54                  074  1-56 

Salt  mackerel  . .         44'45                iQ'i?  22*43  1382        ift\2 

,,     herring     ,.         46'23                 18*90  i6'89  i6'4i         I4'47 

Smoked  herring        69*49                21*12                  8*51  1*24 

SARDINES  IN  OIL.» 

Source.  Water.  Fat.  Proteii.  Ash. 

Sicily  ..  •.  50*16  12*68            4*30  7-51 

Tunis  .,  ..  50*36  i3'o7            4'07  7*85 

Sardinia  ..  ..  40*66  2375            3 '83  8*98 

Some  points  in  these  analyses  are  deserving  of  comment.  The 
first  thing  to  notice  is  the  large  amount  of  waste  matter,  in  the  form 
of  skin,  bones,  etc.,  which  fish  contains.  In  fish,  as  sold,  the  waste 
may  amount  to  fully  70  per  cent.,  while  even  in  fish  as  served  at 
table  it  may  be  as  high  as  35  per  cent.  Another  noteworthy  point 
is  the  large  amount  of  water  in  the  flesh  of  the  leaner  varieties  of 
fish — considerably  more  than  in  lean  meat.  Lastly,  the  relative 
proportions  of  the  nitrogenous  constituents  are  different  from  those 
in  meat,  fish  containing  more  gelatin  (about  four  to  three  in  meat)  and 
fewer  extractives.  Its  greater  richness  in  gelatin-yielding  substance 
causes  fish  to  lose  more  on  boiling  than  meat  does,  and  is  one  reason 
why  boiling  is  by  no  means  the  best  method  of  cooking  fish(seep.  400). 
Its  property  in  extractives  is  the  cause  of  its  lack  of  flavour  as  com- 
pared with  meat,  and  makes  a  fish  diet  apt  to  prove  monotonous. 

2.  Digestibility  of  Fish. — Artificial  experiments  outside  the  body  on 

the  digestibihty  of  fish  have  yielded  discordant  results.     Popoff^ 

arrives  at   the  surprising  conclusion  that  fat  fish  are  more  easily 

digested  than  lean ;  while  *  smoking '  actually  increased  the  rate  of 

digestion,  prolonged  cooking,  on  the  other  hand,  rendering  it  slower. 

He  gives  the  following  table  of  the  relative  quantities  digested  in  a 

given  time : 

Meat,  raw  ..  «,  ..  ..  100 

,,      boiled  ..  ..  ..  ..83 

,,      smoked  ,.  .,  ..  ..  71 

Eel,  raw  ..  ..  ,.  ..  71 

,,     boiled  ..  ..  ,.  ..  68 

,,     smoked  ..  ..  ..  ..  91 

Sole,  raw  ..  ..  ..  ,.  66*8 

„     boiled  ..  ..  ..  ,.  6o"6 

„    smoked  ..  ..  .,  ,,  io6'X 

*  Journal  of  Chemical  Society,  vol.  Ixxii.,  1897,  part  ii.,  p.  335. 

•  Zeit.  jur  Physiolog.  Chtm.,  1890,  xiv.  524. 

6 


82  FOOD  AND  DIETETICS 

Chittenden  and  Cummins,^  using  a  very  similar  method,  got  quit© 
different  results,  for  in  their  hands  the  fat  fish  proved  less  digestible 
than  the  lean,  with  the  exception  of  mackerel,  which  was  rather 
quickly  dissolved.  They  found  that  the  digestibility  of  fish  in  general 
was  below  that  of  beef,  but  several  kinds  were  as  easily  digested  as 
lamb  or  mutton.  Cod,  though  containing  very  little  fat,  proved  to 
be  one  of  the  most  indigestible  of  the  fishes  they  examined. 

Penzoldf^  employed  a  more  natural  method  of  experiment,  fish 
being  eaten  in  the  usual  way,  and  the  time  which  elapsed  before  it 
had  completely  disappeared  from  the  stomach  noted.  He  found  that 
7  ounces  of  white  fish  were  digested  in  two  and  a  half  to  two  and 
three-quarter  hours,  while  a  similar  quantity  of  beef-steak  required 
three  and  a  quarter  hours.  Salt  fish  offered  more  resistance  to  the 
action  of  the  stomach,  7  ounces  of  salt  herring  requiring  four  hours 
for  its  digestion. 

It  must  be  admitted  that  the  results  of  the  last  observer  are  more 
in  harmony  with  those  of  everyday  experience,  which  teaches  that 
the  lean  fish  are  better  borne  by  the  stomach  than  the  fat,  and  are 
apparently  more  easily  digested  than  an  equal  quantity  of  meat.  It 
is  quite  likely  that  fat  interferes  with  natural  digestion  much  more 
than  with  an  imitation  of  the  same  process  carried  out  in  vitro :  for 
not  only  does  fat  seem  to  arrest  the  natural  secretion  of  gastric  juice 
(p.  4 1 9),  but  the  fat  found  in  fish  seems  also  to  be  particularly  apt 
to  become  rancid  and  affect  the  stomach  injuriously  in  that  way. 
That  white  fish  should  be  more  easily  dissolved  by  the  stomach  than 
beef  is  only  what  one  would  expect  from  its  shorter  fibre.  This  is 
specially  evident  in  such  fish  as  the  whiting,  which  on  that  account 
has  been  fancifully  described  as  '  the  chicken  of  the  sea,'  and 
is  frequently  recommended,  and  probably  with  reason,  to  the 
dyspeptic  and  convalescent.  Cod  seems  to  be  an  exception, 
having  a  coarse  fibre,  and  its  comparative  indigestibility,  as  found 
by  Chittenden  and  Cummins,  is  by  no  means  in  contradiction 
with  actual  experience  (Pavy).  The  slow  solution  of  salt  fish 
is  fully  explained  by  the  hardening  of  the  fibres  which  salting 
produces. 

The  absorption  of  fresh  and  smoked  fish  in  the  intestine  takes 
place  quite  as  well  as  that  of  meat,  about  95  per  cent,  of  the  total 
solids,  97  per  cent,  of  the  protein,  and  90  per  cent,  of  the  fat  entering 

*  American  Chemical  Journal,  1884-85,  vi.  318. 

*  Deut.  Archiv  fur  Klin.  Med.,  1893,  li.  535. 


NUTRITIVE  VALUE  OF  FISH  83 

the  blood  (Langworthy).    Salted  and  dried  fish  are  not  quite  so  well 
absorbed.^ 

Nutritive  Value  of  Fish. — The  value  of  fish  as  a  source  of  energy 
depends  entirely  on  the  amount  of  fat  which  it  contains.  The  fat 
fish,  such  as  salmon,  are  fully  equal  to  moderately  fat  meat  in  this 
respect,  while  the  lean  fish,  owing  both  to  the  absence  of  fat  and 
the  presence  of  more  water,  are  of  considerably  lower  nutritive  value. 
It  may  be  reckoned  that  i^  pounds  of  cod  or  other  white  fish  are 
only  equal  in  nutritive  value  to  i  pound  of  lean  beef.- 

As  a  source  of  building  material,  fish  is  somewhat  inferior  to 
lean  meat,  owing  to  the  smaller  amount  of  protein  which  it 
contains.  This  statement  applies  more  strongly  to  lean  fish  than 
to  the  fatter  varieties.  Owing  to  this  smaller  proportion  of  protein, 
and  in  part  also,  in  all  probability,  to  its  lesser  richness  in 
extractives,  fish  seems  to  be  a  less  stimulating  food  than  meat, 
and  on  that  account  is  sometimes  recommended  as  a  substitute  for 
the  latter  in  the  dietary  of  epileptics.  For  the  same  reasons,  white 
fish  may  sometimes  be  used  with  advantage  instead  of  meat  by 
sedentary  persons,  and  in  hot  weather. 

Two  special  qualities  are  erroneously  attributed  to  a  fish  diet  by 
popular  fancy.  I  refer  to  the  beliefs  (i)  that  fish  is  specially 
valuable  as  a  '  brain  food,'  (2)  that  it  possesses  aphrodisiac 
qualities. 

The  former  of  these  opinions  is  grounded  on  the  belief  that  fish 
is  specially  rich  in  phosphorus,  and  the  way  in  which  the  fallacy 
became  promulgated  is  of  some  interest.  I  have  already  referred 
to  the  dictum  of  Biichner,  that  without  phosphorus  thought  is 
impossible  (p.  41).  The  Swiss  naturalist  Agassiz,  knowing  this 
dictum,  and  being  informed  by  the  eminent  chemist  Dumas  that 
fish  contained  much  phosphorus,  put  two  and  two  together,  and 
concluded  that  fish  would  be  specially  good  for  the  brain.  But  we 
have  already  seen  that  the  aphorism  of  Biichner  is  not  altogether 
true,  and  there  is,  further,  no  justification  at  all  for  the  statement 
that  fish  is  rich  in  phosphorus,  and  thus  the  belief  that  it  is 
peculiarly  adapted  for  the  nourishment  of  the  brain,  being  founded 
on  a  double  fallacy,  falls  to  the  ground. 

The  second  belief,  which  attributes  to  a  fish  diet  special  stimu- 
lating powers  on  the  genetic  faculty,  has  been  widely  enter- 
tained,   and    is  advocated    at    some    length    by   Brillat-Savarin    in 

^  SlowtzofF,  Zeit.  f.  Pkysik.  iind  didt.  Therapie,  1910,  xiv.  22, 
^  Rosenfeld  ('Der  Nahrungsv.ert  des  Fischfleisches,'  Zentralb.  f.   inn.   Med., 
1906,  xxvii.  log)  concludes,  as  the  result  of  metabolism  experiments,  that  fish  is 
a  valuable  source  both  of  protein  and  energy,  and  can  be  recommended  to  the 
poor  as  a  substitute  for  meat. 


84  FOOD  AND  DIETETICS 

his  well-known  book.  There  is,  however,  no  sufficient  evidence 
in  favour  of  this  opinion,  and  it  is  contradicted,  as  Pereira  has 
pointed  out,  by  the  fact  that  maritime  populations  are  not  specially 
prolific. 

The  impression  that  fish-eating  produces  a  liability  to  certain 
diseases  of  the  skin,  and  especially  to  leprosy,  is  fcanded  on  some- 
what more  scientific  data,  and  has  been  adopted  by  some  eminent 
authorities,  but  the  discussion  of  the  subject  cannot  be  undertaken 
here.  One  practical  outcome  of  this  belief  has  been  the  abolition  of 
fish  from  th-e  dietary  of  the  patients  in  the  St.  Louis  Hospital  for 
Skin  Diseases  in  Paris. 

Economic  Value  of  Fish. — In  the  case  of  fish,  even  more  than  in 
that  of  most  foods,  the  market-price  is  no  indication  of  the  true 
economic  value.  I  have  already  illustrated  this  fact  by  pointing  out 
(p.  17)  that  although  such  fishes  as  haddock  and  sole  are  of  practically 
the  same  nutritive  value,  yet  the  price  of  the  latter  may  be  four  or 
five  times  that  of  the  former.  On  the  other  hand,  it  by  no  means 
follows  that  none  of  the  dearer  varieties  of  fish  is  worth  the  money. 
Salmon,  for  example,  contains  nearly  three  times  as  much  nutriment 
as  an  equal  weight  of  cod,  and  thus  a  pound  of  the  former  at  is.  6d. 
may  not  really  be  any  dearer  than  a  pound  of  cod  at  6d.  The 
amount  of  waste  in  fish  is  also  of  great  importance  from  the  economic 
point  of  view.  We  have  seen  that  the  inedible  parts  of  fish  as  pur- 
chased may  amount  in  some  cases  to  as  much  as  70  per  cent,  of  the 
tvhole,  and  allowance  must  be  made  for  this  in  calculating  the  real 
cost.  For  this  reason  it  may  be  worth  while  to  pay  a  rather  high 
price  for  canned  or  tinned  fish,  for  in  these  preparations  almost  the 
whole  of  the  material  paid  for  is  in  an  edible  form. 

As  a  general  rule,  it  may  be  said  that  the  cheaper  varieties  of  the 
fat  fishes  offer  most  nutriment  for  any  given  sum.  Salted  white  fish 
probably  rank  next  to  these.  An  average  herring  contains  about 
15  grammes  of  edible  protein  (nearly  ^  ounce)  and  from  5  to 
10  grammes  of  fat,  and  it  has  been  truly  remarked  by  Dr.  Smith  ^ 
that  the  despised  bloater  '  offers  the  largest  amount  of  nutriment  for 
a  given  sum  of  any  animal  food,'  and  two  salt  herrings  contain  as 
much  animal  protein  as  need  enter  into  the  daily  dietary  of  an 
ordinary  working  man. 

The  justice  of  these  remarks  is  borne  out  by  the  following  calcula- 
tions, taken  from  several  made  by  Langworthy,-  English  prices 
being  substituted  for  American: 

*  '  Foods  '  p.  110.  •  •  Fish  as  Food,'  p.  18. 


ECONOMIC  VALUE  OF  FlSIl  85 

COMPARATIVE  COSTS  OF  PROTEIN  AND  ENERGY  AS  FURNISHED 
BY  DIFFERENT  KINDS  OF  FISH. 


Price  per  lb. 

Cost  of  Protein 
per  lb. 

Cost 

of  1,000  Calories 
of  Energy. 

4. 

s.  d. 

s.    d. 

Cod..        „ 

•• 

3 

3  " 

2      Oj 
I      7 

Halibut      .. 

9 

4    9 

Salt  cod     . . 

3h 

I  10 

0    II 

Salt  mackerel 

5 

2  10 

0    5i 
0     6A 

Tinned  salmon 

6 

2  3* 

3  2§ 

Round  of  beef 

7 

0    s' 

Milk 

3d. 

per  quart. 

3     9\ 

0     4i 

The  greater  cheapness  of  the  salt  fish,  and  especially  of  those 
which  are  also  fat,  is  at  once  manifest. 

Of  the  'offal'  of  fish,  the  ovary,  or  rce,  is  alone  commonly  eaten. 
The  roe  of  the  sturgeon,  when  highly  salted,  constitutes  caviare,  the 
best  forms  of  which  come  from  Astrachan.  Good  caviare  should 
be  of  a  grayish  colour — not  black — and  one  should  be  able  to  make 
out  the  separate  eggs  in  it  quite  easily.  It  is  packed  in  vessels 
made  of  lime  wood,  as  it  is  very  apt  to  take  up  foreign  flavours,  and 
of  these  lime  wood  is  destitute.  The  composition  of  caviare— and 
approximately  of  all  fish-roe — is  as  follows  (Langworthy) : 

Water       ..         ..         ,.         ..  .,  38'i  per  cent. 

Protein     ..         ..         ..         ..  ..  300       „ 

Fat  . .         . .         . .         . .  . .  19-7        ,, 

Other  non-nitrogenous  matters  ..  7*6        „ 

Mineral  matter  (including  salt)  ..  4-6 

Fuel  value  per  lb.  ..         ..  ..  1,530  Calories. 

The  proteins  contain  a  good  deal  of  nuclein,  the  significance  of 
which  as  an  article  of  diet  has  already  been  mentioned  (p.  72). 

Three  ounces  of  raw  salted  caviare  are  digested  in  about  two 
hours. 

The  milt  is  the  organ  in  male  fish  corresponding  to  the  roe, 
and  resembles  the  latter  very  closely  in  composition  and  nutritive 
value. 

The  lobster,  crab  and  other  crustaceans,  the  molluscs,  such  as  the 
oyster  and  mussel,  and  the  turtle  and  frog  amongst  reptiles  and 
amphibians,  may  conveniently  be  considered  at  this  point. 

The  lobster  and  crab  both  consist  of  two  distinct  parts  :  the  flesh, 
which  is  contained  in  the  claws  and  tail ;  and  the  body,  which  is 
mainly  made  up  of  liver.  The  general  composition  of  these  parts 
is  thus  contrasted  by  Payen  : 

Flesh.  Body. 

Water         76-6  84-31 

Protein iQ'i'/  12-14 

Fat 117  1-14 


«6  FOOD  AND  DIETETICS 

Konig  gives  the  composition  of  potted  lobster  as  follows: 

Water        ..         ..         ..         ..         ••  5i'33 

Nitrogenous  matter        ..         ..         ..  14 "87 

Fat 24-86 

Other  non-nitrogenous  matter..         ..  404 

Ash             4-90 

Salt            0-38 

That  of  tinned  lobster  is  (Langworthy) : 

Water        ,,  77-8 

Protein i8'i 

Fat i-i 

Carbohydrates     ..         .,         ..         ..  o*6 

Mineral  matter    ..         .«         ,,         ,.  2*4 

The  composition  of  the  crab  is  practically  the  same. 

The  flesh  of  the  lobster  and  crab  is  rather  indigestible,  mainly 
on  account  of  the  density  and  coarseness  of  the  fibres  and  the 
thickness  of  their  walls.  The  use  of  vinegar  helps  to  soften  the 
fibres,  besides  neutraUzing  ammoniacal  salts,  which  are  apt  to  be 
present. 

The  body  of  these  animals  is  also  prone  to  disagree,  not  only 
from  the  fat  which  the  liver  contains,  but  also,  apparently,  from  the 
occasional  development  in  it  of  irritant  poisons. 

Three  ounces  of  potted  lobster  require  about  two  and  a  half  hours 
for  digestion  in  the  stomach. 

The  oyster  is  the  most  typical  and  popular  of  the  molluscs. 
Chemically  it  contains  within  itself  representatives  of  all  three 
nutritive  constituents  of  the  food : 


AVERAGE  COMPOSITION  OF  OYSTERS  (Langworthy). 

(Exclusive  of  Liquid.) 

Water        ,         .,  88*3 

Nitrogenous  substances  .♦         ..         ••  6*1 

Fat 1*4 

Carbohydrates     ..          ..         ••         ..  3*3 

Salts           ..          ..         ..         ..         ..  i'9 

The  proportion  of  solid  nutriment,  however,  is  not  large,  three 
dozen  moderate-sized  oysters  having  only  from  2f  up  to  5^  ounces 
of  solids.  It  is  probable,  too,  that  the  nitrogenous  matter  which 
they  contain  is  not  all  in  the  form  of  protein,  but  is  partly  present 
as  other  compounds  of  lower  nutritive  value. 

Glycogen  is  the  form  in  which  carbohydrate  is  present  in  oysters. 
It  is  contained  in  the  liver.     Its  presence  renders  oysters  an  iin- 


OYSTERS  87 

suitable  food  in  cases  of  diabetes  in  which  a  strict  diet  is  being 
enforced. 

The  oyster  is  rightly  regarded  as  an  easily-digested  food — at  least, 
if  taken  raw.  Three  medium-sized  oysters  are  entirely  disposed  of 
by  the  stomach  in  one  and  three-quarters  hours.  Cooking  renders 
them  tough  and  less  easily  digested. 

The  nutritive  value  of  oysters  is  not  high.  A  dozen  Ostend  oysters 
contain  about  5  grammes  of  digestible  protein  and  i^  grammes  of 
fat.  It  would  take  fourteen  of  them  to  contain  as  much  nourish- 
ment as  one  egg,  and  223  to  equal  a  pound  of  beef  (Stutzer).  It  is 
therefore  not  surprising  to  hear  of  enormous  quantities  of  oysters 
being  occasionally  consumed  at  a  sitting.  Brillat-Savarin  relates 
that  he  was  acquainted  with  a  man  who  used  to  eat  a  gross  of  them 
at  a  time,  and  follow  that  up  by  a  heavy  dinner !  They  are  an 
extravagant  form  of  food,  for  a  given  quantity  of  protein  costs  about 
three  times  as  much  in  the  form  of  oysters  as  it  does  if  purchased 
as  beef. 

In  recent  years  oysters  have  to  some  extent  fallen  into  disfavour, 
from  the  belief  that  they  may  be  the  means  of  conveying  the  in- 
fection of  typhoid  fever.  The  belief  is  not  unwarranted,  for  if 
oysters  are  grown  in  estuaries  they  might  easily  enough  become 
infected  with  typhoid  germs  derived  from  sewage,  and  it  has  been 
found  by  artificial  inoculation  that  typhoid  bacilli  thus  introduced 
are  capable  of  surviving  in  the  body  of  the  oyster  for  several  days.^ 
The  risk,  however,  can  be  avoided  by  keeping  the  oysters  alive  for 
a  day  or  two  in  salt  water  which  is  frequently  changed.  This 
washes  them  out  and  destroys  the  bacilli.  Cooking  effects  the 
same  object  with  greater  certainty,  but  at  the  cost  of  diminished 
digestibility. 

The  '  greening '  of  oysters  is  another  subject  which  has  recently 
attracted  a  good  deal  of  attention.  From  their  investigations  into 
the  cause  of  this  phenomenon,  Herdman  and  Boyce  have  concluded 
that  there  are  several  kinds  of  greening,  some  of  which,  such  as 
that  found  in  the  green  Marennes  oysters  and  in  those  of  several 
rivers  on  the  Essex  coast,  are  healthy ;  while  in  others,  such  as  some 
Falmouth  oysters,  the  green  colour  is  associated  with  the  presence 
of  an  excess  of  copper.  Others,  again,  such  as  some  American 
varieties  re-embedded  on  our  coasts,  have  a  pale  green  leucocytosis, 
and  cannot  be  regarded  as  in  a  healthy  state. 

•  Herdroan  smd  Boyce, '  Lancashire  Sea  Fisheries.'  Memoir  I.  :  'Oysters  and 
Disease/ 


88  FOOD  AND  DIETETICS 

Langworthy's  investigations^  led  him  to  a  somewhat  different 
conclusion,  for  he  regards  '  greening  '  as  the  result  of  the  consump- 
tion by  the  oyster  of  certain  forms  of  green  algae,  the  colouring  matter 
of  which  is  soluble  in  the  tissues  and  juices  of  the  oyster,  and 
apparently  harmless. 

After  being  removed  from  the  sea,  oysters  are  sometimes  *  floated ' 
in  brackish  water,  with  the  object  of  '  fattening'  them.  It  has  been 
found,  however,  that  the  apparent  increase  in  plumpness  of  the 
oyster  under  this  treatment  is  really  due  to  the  inhibition  of  moisture 
by  osmosis,  and  that  they  actually  lose  from  one-eighth  to  one-fifth 
of  their  nutritive  value  in  the  process.^ 

The  composition  of  mussels,  clams,  periwinkles,  scallops  and  other 
molluscs  is  very  similar  to  that  of  the  oyster,  and,  like  the  latter,  they 
cannot  be  regarded  as  foods  of  important  nutritive  value.  They  are 
also  peculiarly  liable  to  develop  poisons  which  may  produce  serious, 
and  even  fatal,  symptoms,  and  in  susceptible  persons  their  use  Is 
sometimes  followed  by  irritation  of  the  skin,  usually  taking  the  form 
of  nettle-rash. 

The  green  turtle  is  almost  the  only  reptile  used  for  food  in  this 
country,  and  that  chiefly  in  the  form  of  soup.  It  is  called  green 
because  its  fat  has  a  greenish  colour,  which,  according  to  Sir  Hans 
Sloane,'  imparts  a  yellow  tint  to  the  sweat  of  those  who  partake 
largely  of  it.  In  preparing  the  soup,  the  dorsal  and  ventral  shields 
are  removed,  scalded  to  remove  the  scales,  and  then  boiled  till  the 
bones  separate.  The  liquor  forms  the  stock.  The  softer  parts  of 
the  shield  are  then  cut  into  oblong  pieces,  which  constitute  the 
so-called  lumps  of  green  '  fat ' — really  a  species  of  gelatin.  Sun- 
dried  turtle  forms  a  soup  of  equal  nutritive  value,  and  at  a  consider- 
ably lower  cost,  while  the  basis  of  mock-turtle  is  the  gelatinous 
substance  in  the  scalp  of  the  calf.  From  a  strictly  nutritive  point 
of  view,  turtle  soup  is  certainly  not  worth  a  tenth  of  the  price 
paid  for  it. 

Frogs'  legs  are  but  rarely  seen  in  this  country,  though  common 
articles  of  diet  on  the  Continent.  They  are  derived  from  the  large 
edible  frog  {Rana  esculenta),  and,  though  easily  digested  and  of  a 
delicate  flavour,  are  not  of  high  nutritive  value. 

The  average  chemical  composition  of  the  different  groups  of  foods 
studied  in  this  chapter  is  represented  in  the  following  diagram, 

*  '  Fish  as  Food,"  p.  17. 
»  Ibid.  p.  16. 

•  See  Pereira,  '  On  Food  and  Diet,'  p.  273. 


THE  TURTLE  AND  FROG 


89 


which  also  gives  some  idea  of  their  relative  nutritive  values.     It  is 
constructed  from  the  analyses  published  by  Langworthy. 


ntESU  PISH 


W«*TS     m      W*TER.      P^]    PROTEIN    ^^  »iT      p^  ASM 

FlO.    7. — COMPARATrVB   COMPOSITION  OV  FiSH   AND   THEIR  ALLIES. 


[  9>  ] 


CHAPTER  VI 

SOUPS.  BEEF-EZTBAOTS,  BEEF-JUICES.  BEEF-TEA,  AND 
BEEF-FOWDEBS 

When  meat  is  cut  up  and  placed  in  water  for  the  purpose  of  making 
soup,  there  is  dissolved  out  of  it  (i)  a  small  proportion  of  its  soluble 
proteins  ;  (2)  a  large  part  of  its  extractives  and  mineral  matter ; 
(3)  a  small  quantity  of  fat.  If  the  water  is  now  raised  to  the 
boiling-point,  the  protein  is  coagulated  and  floats  to  the  top  as  a 
brownish  '  scum,'  which  is  usually  carefully  skimmed  off.  At 
the  same  time  the  proportion  of  extractives  and  mineral  matter  in 
the  solution  is  increased,  and  some  of  the  connective  tissue  is  dis- 
solved out  in  the  form  of  gelatin. 

It  will  be  evident  from  these  considerations  that  a  clear  soup 
contains  chiefly  the  Jlavoimng  constituents  of  the  meat  from  which  it 
is  prepared.  The  amount  of  nutritive  matter  in  it  is  very  small, 
for  a  solution  of  gelatin  of  even  1  per  cent,  strength  '  sets,'  and  very 
few  soups  contain  as  much  as  that.  This  estimate  of  the  nutritive 
value  of  a  clear  soup  is  borne  out  by  the  following  example  :i  i  pound 
of  beef  and  about  J  pound  of  veal  bones  were  boiled  down  in  the 
usual  way,  and  yielded  i  pint  of  strong  soup.  Analysis  of  this 
showed  that  it  contained  95  per  cent,  of  water  and  only  5  per  cent, 
of  solids,  made  up  in  almost  equal  proportions  of  fat,  gelatin,  and 
extractives,  along  with  a  small  proportion  of  mineral  matter.  And 
yet  this  was  a  strong  soup.  Most  clear  soups  contain  only  from  i^  to 
2|  per  cent,  of  solids.  As  an  ordinary  soup-plate  holds,  when  full, 
about  7  ounces,  a  large  helping  of  the  above  strong  soup  would  only 
yield  to  the  consumer  about  J  ounce  of  solid  matter,  and  even  of  that 
only  the  gelatin  and  fat,  say  about  |  ounce,  are  really  '  foods.' 

Seeing  that  it  is  chicHy  the  flavouring  materials  of  tlie  meat  which 

>  Atwuter.  '  Chemistry  and  Economy  of  Food,'  p.  8^. 


SOUPS  91 

are  removed  in  making  soup,  it  is  obvious  that  we  cannot  get  a 
good  soup  and  a  well-flavoured  dish  of  meat  from  the  same  piece  of 
beef.  You  cannot  both  eat  your  cake  and  have  it ;  and  although  it 
is  true  that  the  meat,  after  the  soup  is  made,  has  lost  practically 
none  of  its  nutritive  qualities,  yet  its  sapid  and  appetizing  elements 
are  gone. 

If,  then,  one  wants  to  make  soup  nourishing,  one  must  simply  use 
it  as  a  vehicle  by  means  of  which  other  food  materials  added  to  it 
can  be  conveyed  into  the  stomach.  Starchy  materials  are  often 
added  in  this  way,  cornflour  being,  perhaps,  one  of  the  commonest. 
Barley  is  similarly  used  in  barley  broth.  In  potato  soup,  too,  the 
soup  is  simply  a  vehicle  for  a  considerable  amount  of  potato  starch. 
In  other  cases  nitrogenous  matter  is  added,  such  as  grated  cheese  or 
macaroni  (which  contains  a  good  deal  of  gluten),  or  the  soup  is 
thickened  by  the  addition  of  one  of  the  pulses,  e.g.,  peas  or  lentils, 
the  latter  being  amongst  the  most  nutritit  as  soups.  Animal  matters 
may  be  also  be  employed,  as  in  the  preparation  of  purees  of  chicken, 
fish,  or  game.  The  following  analyses  of  two  tMck  soups  are  taken 
from  Konig : 

Water. 

Pea  soup    ..     88-26 
Potato  soup    90*96 

Even  in  these  cases  the  nutritive  value  cannot  be  regarded  as  high, 
for  half  a  slice  of  bread  would  contain  as  much  solid  matter  as  a  full 
plateful  of  such  a  soup. 

It  must  not  be  supposed,  however,  that  clear  soups  are  of  no 
dietetic  value.  It  is  not  an  error  to  begin  dinner  with  soup.  It  has 
been  found  that  it  is  just  those  very  materials  (extractives  and 
gelatin)  which  a  clear  soup  contains  which  are  most  calculated  to 
promote  a  flow  of  gastric  juice,  and  so  to  further  the  complete 
digestion  of  the  solid  food  subsequently  introduced  into  the  stomach. 
As  a  French  writer  has  said,  soup  should  be  to  a  dinner  what  the 
overture  is  to  an  opera  or  the  porch  is  to  a  house.  It  is  a  good  intro- 
duction. If,  then,  one  gets  the  choice  of  '  clear  '  or  '  thick,'  it  may 
be  well,  if  a  solid  meal  is  to  follow,  to  select  *  clear ' ;  but  if  the  soup 
itself  is  to  be  the  piece  de  resistance,  one  should  certainly  choose  '  thick.' 
For  this  reason,  when  soup  is  served  out  at  penny  dinners  or  soup- 
kitchens,  it  should  always  be  made  as  thick  as  possible,  preferably 
by  the  addition  of  one  of  the  pulses,  such  as  lentils  or  peas.  In  the 
case  of  an  invalid,  a  *  strong  soup '  may  be  a  useful  means  of  rousing 


Other 

Nitrogenous 

F«t. 

Nitrogen- 

Cellu- 

Mineral 

Matter. 

free 

lose. 

Matter. 

Substances. 

3-38 

0-93 

5 '60 

070 

I-I3 

1-37 

i"53 

4-87 

0*26 

0-99 

94  FOOD  AND  DIETETICS 

the  appetite  and  stimulating  the  digestive  powers  of  the  stomach, 
but  it  cannot  be  regarded  in  itself  as  a  serious  contribution  to  his 
nutrition. 

Beef- Extracts. 

The  valuable  culinary  qualities  of  an  extract  of  meat  were  first 
recognised  by  Proust,  but  it  was  not  until  the  matter  was  taken  up 
by  Baron  Liebig  that  they  became  at  all  widely  known. ^  The 
extract  was  first  prepared  on  a  commercial  scale  by  the  company 
authorized  by  Liebig  in  the  year  1865.  The  factory  was  estab- 
lished in  South  America,  as  cattle  can  be  obtained  there  much  more 
cheaply  than  in  Europe, 

The  method  of  preparation  is  simple.  The  fresh  meat  is  simply 
chopped  up,  heated  under  pressure  with  a  little  water,  the  extract 
filtered  and  evaporated  in  vactw  and  in  the  open.  The  product  is 
the  brown,  sticky  material  with  which  everyone  is  familiar.  A  good 
sample  should  have  a  rather  golden-brown  colour.  If  too  dark,  it 
has  probably  been  burnt,  and  it  should  have  a  strong  and  agreeable 
'  meaty '  odour. 

Liebig  calculated  that  34  pounds  of  pure  beef  should  yield  i  pound 
of  the  extract,  and  that  this  should  make  70  pints  of  beef-tea,  every 
pint  therefore  corresponding  to  ^  pound  of  beef.  He  fixed  the  com- 
position of  the  article  to  be  sold  thus  : 

Moisture  may  vary  from         ..         .,         ,,     16  to  21  per  cent. 
Mineral  matter  may  vary  from  ..         ..     18  ,,  22        „ 

E-xtractives  may  vary  from     ..         ..         ..     56  ,,  60         „ 

Liebig  expressly  forbade  the  sale  of  any  extract  containing 
gelatin.  The  latter  substance  is  so  cheap,  he  said,  that  it  would 
tempt  people  to  add  it  as  an  adulteration,  and  would  also  prevent 
the  extract  from  keeping.  It  would  then  sink  to  the  level  of  '  tablets 
of  consomm6,'  which  he  regarded  as  '  a  kind  of  coloured  glue.'  He 
likewise  discountenanced  the  addition  of  any  salt. 

It  will  be  observed  that  into  the  composition  of  Liebig's  extract 
as  fixed  by  its  inventor  no  proteins  or  albuminoids  enter.  A  vast 
number  of  analyses,  however,  have  been  made  of  it  in  more  recent 
times,  some  of  which  have  credited  it  with  containing  these  valuable 
nutritive  constituents  in  considerable  amount.  Amongst  the  most 
striking  of  these  is  an  analysis  by  Kemmerich,^  which  yielded  the 
following  results : 

*  See  Thudichum, '  Origin,  Nature,  and  Uses  of  Liebig's  Extract,'  London,  1869. 

•  Zeit./ur  Physiolog.  Chemie,  1894,  xviii.  409. 


BEEF-EXTRACTS 


93 


Composition  of  Ltebig's  Extract  according  to  Kemmench. 

Water 1 8  per  cent. 

Proteins ..         ..         ..         ..         ..         .,         ../ 

Gelatin |  3o 

Extractives        ..         ..         ..         ..         ..         ••25        „ 

Mineral  matter  20        „ 

Ether  extract,  etc.        ..         ..         ..         ..         ..       7        „ 

This  was  certainly  a  very  startling  result,  but  it  was  not  allowed 
to  go  long  unchallenged,  for  Konig  and  Bomer^  have  submitted  the 
above  analysis  to  a  searching  criticism,  and  have  shown,  and  I  think 
conclusively,  that  it  was  arrived  at  by  faulty  methods.  They  point 
out  that  one  could  not  a  priori  expect  Liebig's  extract  to  contain 
much  gelatin,  for  heat  is  only  employed  in  its  preparation  to  a  small 
extent,  and,  further,  solutions  of  it  do  not  gelatinize.  They 
show  that  it  contains  only  about  7  per  cent,  of  albumoses,  and 
perhaps  traces  of  peptone,  but  certainly  not  more  than  i  per  cent,  of 
gelatin,  and  distribute  the  amount  of  nitrogen  which  it  contains 
thus: 

Total  nitrogen           ,  ,.  9-28  per  cent. 

Nitrogen  in  the  form  of  soluble  albumin  . .  Trace 

Albumoses     ..          ..          ..          ..          ..  ,.  0*96  per  cent. 

Peptone  Nil  to  a  trace. 

Meat  bases     ..         ..         ,.         .,         ..  ..  6'8i  per  cent. 

Ammonia  compounds          ..          ..         ..  ..  0*47         ,, 

Other  nitrogen  compounds           .,         ..  ..  o"83        ,, 

More  recent  analyses  of  Liebig's  extract  (*  Lemco ')  by  the 
Lancet^  gives  the  following  as  its  range  of  composition  : 


Moisture 
Mineral  salts  . . 
Organic  matter 


Total  nitrogen 


Albumose 
Peptone 


From  17-12  per  cent,  to  21-50  per  cent. 


10  J5 
55 '34 

9-48 

8-52 
3  "34 

I4'I2 


26-30 
62-43 

11-62 

14-26 
5  60 

1934 


9-00 

>> 

1250 

0-25 

>i 

088 

2-68 

It 

5-69 

3  06 

6  70 

Total  proteins    . . 

Creatin  and  creatinin 
Insoluble  matter 
Sodium  chloride 
Phosphoric  acid  (PoOj) 

Although,  therefore,  small  amounts  of  albumose  and  peptone  are 
present,  it  is  upon  the  extractives  that  the  uses  and  value  of  the 
extract  must  chiefly  depend,  and  for  that  reason  we  must  now  look 
a  httle  more  closely  at  their  chemical  and  physiological  properties. 

*  Zeit.  fur  Analyt.  Chemie,  1895,  xxxiv.  548. 

'  Report  of  Special  Commission  upon  the  Origin,  Manufacture,  and  Uses  of 
Extract  of  Meat,  Lancet,  190S,  ii.  1233. 


94  FOOD  AND  DIETETICS 

On  the  chemical  properties  of  the  extractives  of  meat  we  have  but 
scanty  information.  Most  of  them  are  basic  substances ;  a  few  are 
amides.  Creatin,  xanthin,  carnine,  and  the  peculiar  and  interesting 
substance  carnic  acid,  which  seems  closely  to  resemble  the  so-called 
'  anti-peptone,'  are  amongst  the  best  known.  These  substances 
represent  the  fragments,  as  it  were,  of  broken-down  protein,  and  are 
of  no  use  as  tissue-builders. 

They  bear  very  much  the  same  relation  to  protein  as  sand  does  to 
the  sandstone  out  of  which  it  has  been  crushed,  and  it  is  as  hopeless 
to  expect  to  build  up  tissues  from  them  as  it  would  be  to  construct 
a  house  out  of  sand.  They  are  also  incapable  of  being  oxidized  in 
the  body,  and  so  are  useless  as  sources  of  heat  or  energy.  Being 
neither  tissue-builders  nor  energy-producers,  they  cannot  be  regarded 
as  foods.  Experiment  confirms  this,  for  it  was  found  that  rats 
which  were  fed  on  4  grammes  of  meat-extract  daily  died  quite  as 
soon  as  other  rats  which  got  no  food  at  all,  and  Jessop^  quotes  a 
writer  who  consumed  half  a  pot  of  Liebig's  extract  at  a  sitting,  and 
yet  felt  as  hungry  as  ever  afterwards. 

To  do  Liebig  justice,  he  recognised  this  himself.  *  Meat-extract,' 
he  says  somewhere,  '  cannot  make  us  strong,  but  it  makes  us  aware 
of  our  strength.'  We  have  here  introduced  the  notion  that  the 
extractives  of  meat  act  as  '  stimulants,'  a  view  which  has  since  been 
frequently  maintained.  It  must  be  admitted,  however,  that  satis- 
factory evidence  for  any  belief  in  the  '  stimulating  '  properties  of 
beef-extract  is  not  forthcoming.  A  *  stimulant '  must  act  either  on 
the  heart,  quickening  and  strengthening  its  action,  or  upon  the 
central  nervous  system,  abolishing  or  lessening  fatigue.  Now,  it 
has  been  shown  that  2  ounces  of  Liebig's  extract  can  be  taken  at 
one  time  by  a  healthy  man  without  the  production  of  any  effect 
other  than  slight  diarrhoea.^  Certainly  no  increase  in  the  rapidity 
or  force  of  the  pulse  was  observed. 

Of  course,  if  the  extract  be  taken,  as  it  usually  is,  dissolved  in  hot 
water,  the  heart's  action  may  easily  be  increased,  but  the  sipping  of 
hot  water  by  itself  is  quite  capable  of  producing  such  an  effect.  On 
the  other  hand,  the  danger  of  any  depression  of  the  heart  from  the 
action  of  potash  salts  contained  in  the  extract  seems  to  have  been 
greaily  exaggerated.  It  has  been  conclusively  shown  that  even 
large  doses  of  potash  salts  have  no  effect  on  the  pulse. ^ 

*  Brit.  Med.  Joum.,  1889,  ii.  462. 

»  See  Lehmann,  Archiv.  jur  Hygiene,  1885,  iii.  249:  and  Bunge,  PflUger's 
Archiv.,  1871,  iv.  234. 

*  See  Bunge  and  Lehmann  (loc.  cit.)  :  100  grammes  of  meat  boiled  for  throe 
hours  yielded  2-87  grammes  of  extract  with  0*37  gramme  of  potash  salts. 


BEEF  EXTRACTS  95 

As  regards  an  influence  on  the  nervous  system  the  evidence  is 
equally  unsatisfactory.  There  is  no  proof  that  the  extractives  of 
meat  act  as  brain  stimulants  in  the  way  that  tea  and  coffee  do,  but 
there  is  some  evidence ^  that  they  are  capable  of  removing  the  effects 
of  muscular  fatigue,  so  enabling  an  exhausted  muscle  to  become 
active  again.  This  may  explain  the  beneficial  effects  which  seem 
sometimes  to  follow  the  administration  of  beef  extract  in  fatigue. 

It  has  been  suggested  that  the  action  of  the  extractives  in  diminish- 
ing fatigue  is  comparable  to  the  use  of  oil  in  machinery.  '  Friction' 
is  lessened  and  effort  rendered  easier.  It  must  be  remembered  that 
this  is  a  mere  suggestion,  unsupported  by  any  definite  evidence,  but 
at  the  same  time  one  has  to  face  the  fact  that  clinical  observers 
have  repeatedly  affirmed  the  refreshing  quahties  of  a  solution  of  the 
extractives  of  meat.  '  What  more  invigorating  remedy,  more  power- 
fully acting  panacea,'  says  Proust,  *  than  a  portion  of  genuine 
extract  of  meat,  dissolved  in  a  glass  of  noble  wine  ?' 

Whilst  the  stimulating  properties  of  the  extractives  of  meat  must 
be  regarded  as  somewhat  doubtful,  there  can  be  no  question  at  all 
of  their  marked  effect  on  the  digestive  organs.  The  recent  experi- 
ments of  Pawlow  have  shown  that  they  are  the  most  powerful 
exciters  of  gastric  secretion  that  we  possess.  They  are  thus 
eminently  calculated  to  rouse  appetite  and  aid  the  digestion  of  any 
food  with  which  they  may  be  taken.  This,  indeed,  is  their  true 
function,  both  in  health  and  disease.  They  are  flavouring  agents,  and 
their  proper  place  is  in  the  kitchen,  not  by  the  bedside.  As  Voit 
has  rather  fancifully  put  it,  the  influence  of  such  substances  as  the 
extractives  of  meat  on  the  nervous  system  is  mainly  an  aesthetic  one, 
and  is  comparable  to  the  influence  of  a  symphony  by  Beethoven  on 
the  ear,  or  of  a  picture  by  an  old  master  on  the  sense  of  sight. 

Professor  Thompson 2  has  shown  that  the  addition  of  a  small 
amount  of  beef  extract  to  the  diet  leads  to  an  increase  of  weight  both 
in  men  and  animals,  and  to  a  rise  in  the  retention  of  nitrogen  in  the 
body.  Whether  these  results  are  to  be  ascribed  solely  to  an  im- 
provement in  digestion  and  absorption,  or  whether  the  beef  extract 
contains  some  substance  (?  a  vitamine)  which  exercises  a  specific 
effect  upon  metabolism  is  uncertain,  but  at  all  events  the  experi- 
ments are  highly  interesting  and  important. 

We  may  conclude,  then,  that  Liebig's  extract,  though  containing 
too  little  protein  matter  to  be  in  itself  a  food,  may  act  as  a  valuable 
adjuvant  to  other  foods,  especially  where  appetite  and  digestion  are 

1  See  Kcbert,  Archiv  fay  Exper.  Path,  utti  Pharmak.,  1S82,  xv.  60. 
■  Brit.  Med.  Joum.,  1911,  ii.  613. 


$6  FOOD  AND  DIETETICS 

feeble.     The  possible  value  of  the  salts  which  it  contains  will  be 
discussed  when  we  consider  beef-tea. 

What  is  meant,  then,  or  ought  to  be  meant,  when  one  says  that 
I  pound  of  the  extract  is  the  equivalent  of  34  pounds  of  meat,  is  that 
it  contains  all  the  flavouring  ingredients  of  the  latter.  It  does  not  in 
any  sense  contain  the  nutritive  matter  of  that  quantity  of  meat.  As 
one  might  have  expected,  the  fact  that  Liebig's  extract  is  of  very 
small  nutritive  value  was  not  long  in  being  recognised,  and  numerous 
rival  preparations  have  sprung  up  which  profess  to  contain,  in 
addition  to  the  flavouring  ingredients  of  meat,  some  or  all  of  its 
nutritive  constituents.  These  are  made  by  adding  to  the  watery 
extract  obtained  from  the  meat  a  proportion  of  the  meat  fibre  which 
is  left  behind.  In  no  case,  however,  does  the  whole  of  the  fibre  of 
the  meat  seem  to  be  returned  to  the  extract.  The  reason  why  one 
believes  this  is  clearly  stated  by  Allen. ^  '  In  the  lean  of  meat  the 
proteins  bear  to  tic  sum  of  the  extractives,  meat  bases  and  salts 
the  proportion  of  about  4  to  i.  Hence,  if  all  the  meat  fibre,  etc., 
were  again  added  to  the  extract,  the  product  would  contain  the 
solids  of  meat  in  the  same  relative  proportions.  Assuming  in  a  pre 
paration  the  presence  of  70  per  cent,  of  extractives,  etc.,  and  10  per- 
cent, of  meat  fibre,  it  follows  that  only  about  i  part  out  of  28  parts 
of  fibre  separated  has  been  returned  to  the  extract.'  That  the  pro- 
portion of  proteins  to  extractives  and  mineral  matter  in  most  of  these 
preparations  is  really  not  much  greater  than  i  to  7  will  be  evident 
on  an  inspection  of  the  analyses  in  the  table  on  p.  97. 

It  will  be  observed  that  the  proportion  of  insoluble  protein — 
i.e.,  meat  fibre— is  not  really  high  in  any  of  these  preparations, 
whilst  the  amount  of  soluble  proteins  is  no  greater  than  it  is  in 
ordinary  meat  extract.  As  regards  meat  'Essences' — f.g.,  Brand's 
— the  percentage  of  water  is  so  high  that  the  nutritive  value  of  the 
preparation  is  almost  negligible,  and  depends  entirely  upon  small 
quantities  of  soluble  proteins  and  gelatin.  The  same  is  true  of 
chicken  jelly'  and  similar  products  which  are  so  largely  used  in 
the  sick-room.  They  are  mildly  stimulating,  and  tend  to  promote 
appetite,  but  their  contribution  to  the  nutrition  of  a  patient  is 
negligible.  When  one  adds  to  that  the  consideration  of  their 
expense,  it  will  be  realized  that  they  are  essentially  luxuries,  and  are 
not  to  be  regarded  as  in  any  respect  necessary  adjuncts  of  invalid 
cuisine.  They  have  the  advantage,  however,  as  compared  with 
ordinary  meat  extracts,  of  containing  less  salt  and  other  mineral 
matters,  and  can  thus  be  taken  in  larger  quantities  without  causing 
thirst  or  diarrhcea,  or  throwing  a  strain  upon  the  kidneys. 

^  '  Commercial  Organic  Analysis,'  iv.  304,  footnote  (and  edit). 


BEEF-EXTRACTS 


97 


COMPOSITION  OF  BEEF-EXTRACTS.  ETC.* 


•  Oxo." 

Nursing 
•  Oxo.' 

BovriL 

Invalid 
Bovril. 

Brand's 
Essence. 

Armour'i 
Extract. 

Water 

Insoluble  protein  . . 
Albumoses  and  pep- 
tone 

Extractives,  etc.     . . 
Mineral  matter 

39-71 
4-61 

1350 

24  14 
1804 

23-27 

5-83 

33-51 

21-7 
1573 

38-10 
840 

384 

31-79 
17-87 

21-82 

39'6o 
17-16 

87-17 

io'4 

(5  =  gelatin) 

I -01 

1-39 

24-30 
1-58 

1450 

4056 
1903 

Bo-vxil  is  one  of  the  best  known  of  the  preparations  which  contain 

meat  fibre.     The  composition  of  its  solid  matter,  compared  with  the 

solid  matter  of  lean  meat,  is  thus  given  by  Voit :' 

Bovril  {Dried).  Meat  (Dried). 
Organic  matter       ..         ..         ..         ..     753  94-6 

Mineral  matter       ..         ..         ,.         ..     24-7  5*3 

Proteins       ..         ,,         ,,         ,.         ..     49-7  86-7 

Extractives..         ..         ..         ,.         ..     25*6  7*8 

Voit  concludes  that  only  a  small  part  (6  per  cent.)  of  meat  fibre 
has  been  added  to  the  extract  in  this  case. 

Whilst  the  title  of  '  food '  cannot  be  denied  to  these  preparations, 
seeing  that  they  do  contain  a  certain  amount  of  protein,  yet  they  are 
only  foods  in  theory.  Practically,  they  cannot  be  taken  in  sufficient 
quantity  to  enable  them  to  be  really  able  to  contribute  to  nutrition. 
Even  in  the  case  of  Bovril,  a  full  teaspoonful  only  contains  as 
much  protein  as  -J-  ounce  of  meat,  and  it  would  require  about 
14  ounces  of  such  a  preparation  to  supply  an  invalid  with  the  amount 
of  protein' he  requires  daily;  but  such  a  quantity  he  would  find  it 
impossible  to  consume,  owing  to  the  enormous  quantity  of  salts  and 
extractives  which  it  would  contain.  As  a  matter  of  fact,  the  white 
of  one  egg  will  contain  as  much  nutritive  matter  as  three  teaspoon - 
fuls  of  any  of  the  preparations  in  the  above  table.  I  cannot,  therefore, 
think  that  these  preparations  are  to  any  practical  extent  superior  to 

^  This  table  contains  analyses  collected  from  various  sources.  Where  more 
than  one  analysis  of  any  preparation  exists,  that  which  seemed  most  trustworthy 
has  been  selected.  The  results,  however,  must  be  regarded  as  merely  approxi- 
mative, absolute  accuracy  in  the  analysis  of  these  preparations  being  hard  to 
attain  owing  to  technical  difficulties  in  the  separation  of  the  different  constituents. 
This  may  help  to  explain  the  very  discordant  results  often  arrived  at  by  different 
investigators.  For  further  analysis  of  these  and  similar  preparations,  see  Allen's 
'  Commercial  Organic  Analysis,'  iv.  ;  Chittenden  (Medical  News,  Philadelphia, 
1891,  Iviii.  716),  Food  and  Sanitation  (1893  and  1896),  and  Leyden's  '  Handbacb 
der  Ernahrungstherapie,'  Bel.  i. 

*  Milnch   Med.  Wockensch..  1897,  ^^^'■' ■  '^^9- 

f 


98  FOOD  AND  DIETETICS 

those  which  contain  the  extractives  only.  It  is  not  a  question,  as 
Voit  says,  of  whether  a  preparation  contains  nutritive  matter  or  not, 
but  of  how  much  it  contains,  and  one  might  as  well  add  a  pinch  of 
dried  meat  to  a  cup  of  tea  to  render  it  'nutritious,'  or  say  that  air  is 
nutritious  because  it  contains  organisms  which  would  in  an  infini- 
tesimal degree  help  to  feed  one,  as  hope  to  obtain  any  real  nourish- 
ment by  the  use  of  such  preparations  as  these.  Not  only  so  ;  the 
expense  of  these  manufactured  articles  Avould  alone  render  their  use 
as  foods  impossible.  One  may  take  it  that  even  the  cheaper  members 
of  the  group  would  only  yield  the  80  grammes  or  so  of  protein 
which  an  invalid  requires  daily  at  an  outlay  of  six  or  seven  shillings 
per  day. 

Recently,  extracts  prepared  from  yeast  have  been  introduced 
as  substitutes  for  ordinary  meat  extracts.  A  good  example 
of  these  is  the  preparation  known  as  Marmite,^  which  has  the 
following  composition : 

Per  Cent. 

Water 26-84 

Extractives        ..         ,,  ..         ..       34'67 

Proteins..         ..         ..         ..         ,.       lo'^o 

Mineral  matter . .         ..         ..         ..       26*95 

Such  preparations  resemble  beef-extracts  so  closely  in  their  general 
characters  that  they  have  even  been  used  in  the  adulteration  of 
genuine  meat  extracts.^  The  chief  chemical  difference  between 
beef-extract  and  an  extract  of  yeast  appears  to  consist  in  the  presence 
of  creatin  and  creatinin  in  the  former,  and  their  absence  in  the 
latter ;  yeast  extract  also  contains  relatively  more  of  the  base 
adenine.^  Whether  these  slight  chemical  differences  involve  a 
different  action  in  the  body  is  still  undetermined,  but  there  is  no 
reason  to  believe  that  yeast  extract  is  in  any  way  unwholesome, 
although  it  may,  perhaps,  not  have  quite  the  same  stimulating  effect 
on  gastric  secretion  that  genuine  meat  extracts  have.* 

^  Analysis  supplied  by  the  makers. 

^  For  the  method  of  distinguishing  yeast  extract  from  genuine  meat  extract, 
see  papers  by  A.  Searl,  F.C.S.,  in  the  Pharmaceutical  Journal,  1903,  4th  series, 
xvii.  516,  704. 

•*  See  a  paper  by  Gamgee  ('Are  Yeast  Extracts  justifiable  as  Substitutes  for 
Extract  of  Meat  ?'),  Brit.  Med.  Journ.,  1908,  ii.  449,  and  a  reply  to  it  by  Chapman 
{Ibid.,  1908,  ii.  1741). 

*  Helluer  ('  Hefe  Extracte '),  Zeit.  f.  Hygiene,  1903,  xlii.,  461,  and  Hoffmann  and 
Wintgen,  Arch.  f.  Hyg.,  1907,  Ixi.  187, 


BEEF -JUICES  99 


Beef-juices. 

Clearly  to  be  distinguished  from  the  btef-extracts  is  the  group  of 
preparations  known  as  beef-juices.  As  their  name  implies,  these  are 
intended  to  consist  of  the  'juice '  of  meat — i.e.^  of  the  fluid  substance 
contained  in  the  muscle  fibres.  They  are  prepared  by  subjecting  the 
meat  to  strong  pressure,  and  are  subsequently  concentrated  by 
evaporation  in  vacuo.  The  use  of  heat  must  be  carefully  avoided 
in  their  manufacture,  as  it  would  coagulate  the  soluble  proteins 
contained  in  the  juice.  This  is  what  is  meant  when  one  reads  that 
such  and  such  a  beef-juice  '  is  prepared  by  a  cold  process ' ;  and  as 
the  plant  necessary  to  carry  out  the  evaporation  is  rather  expensive, 
the  cost  of  these  preparations  is  necessarily  high.  Further,  as  one 
would  expect,  they  are  liable  to  undergo  putrefaction  after  manufac- 
ture, and  this  in  many  of  them  is  guarded  against  by  the  addition  of 
some  salt  or  glycerine  or  other  harmless  preservative.  That  they 
do  in  reality  contain  the  juice  of  raw  meat  is  shown  by  the  fact  that 
many  of  them  at  least  yield  the  spectrum  of  oxy-haemoglobin. 

In  order  better  to  appreciate  the  relative  values  of  these  prepara- 
tions, we  must  first  look  for  a  moment  at  the  composition  of  natural 
raw-beef  juice  as  prepared  at  home. 

Raw-beef  juice  may  be  prepared  in  various  ways.  One  is  by  the 
method  of  expression.  If  beef  be  squeezed  very  hard,  juice  exudes 
from  it  just  as  it  would  from  an  orange.  Expression  may  be  carried 
out  at  home  by  means  of  a  lemon-squeezer  ;^  but  this  is  a  wasteful 
method,  as  it  only  succeeds  in  removing  a  part  of  the  total  amount 
of  juice.  By  the  use  of  suitable  presses,  wholesale  manufacturers 
succeed  in  obtaining  a  much  larger  yield  of  juice  from  a  given 
weight  of  beef. 

Another  method  is  the  old-fashioned  one  of  cutting  the  meat  into 
small  squares,  and  placing  these  in  a  tightly- corked  bottle,  which  is 
then  immersed  in  a  saucepan  of  water,  which  is  gradually  heated 
^till  the  water  almost  boils.  The  bottle  is  then  left  in  this  hot 
water  for  two  or  three  hours.  As  a  result  of  the  heat  the  meat 
contracts,  squeezing  out  as  it  does  so  a  considerable  quantity  of 
rich  juice.  This  method  is  also  wasteful,  and,  unless  the  heat 
be  carefully  regulated,  some  of  the  protein  in  the  juice  is  apt  to  be 
coagulated, 

1  The  Hercules  Patent  Meat-Juice  Press  is  a  much  more  efficient  apparatus, 
giving  a  yield  of  about  50  per  cent. 


lOO 


FOOD  AND  DIETETICS 


Perhaps  the  best  method  of  all  is  to  chop  up  the  meat,  and  extract 
the  juice  from  it  by  the  addition  of  cold  water.  If  the  mixture  be 
left  to  stand  for  some  time  in  a  cool  place,  the  soluble  proteins  and 
other  constituents  of  the  meat  are  gradually  dissolved  out,  and  are 
obtained  on  squeezing  out  the  pulp  in  muslin.  Of  course,  the 
juice  so  obtained  is  somewhat  diluted,  but  to  make  up  for  this  one 
obtains  a  larger  quantity  of  it.  This  is  certainly  the  most  economical 
method  of  procedure. 

The  following  table  shows  the  composition  of  raw-beef  juice 
obtained  by  these  different  methods.  The  composition  of  the  juice 
varies  somewhat  according  to  the  method  employed  in  preparing 
it,  the  amount  of  coagulable  protein  rising  in  one  case  to  nearly 
7  per  cent.,  while  in  another  it  is  as  low  as  2  per  cent.  The 
proportion  of  extractives  also  varies  a  little. 

In  an  experiment  which  I  made  myself,  half  a  pound  of  good  lean 
beef  was  taken  and  passed  through  a  sausage-machine.  Its  own 
bulk  of  water  was  then  mixed  with  it,  and  the  whole  allowed  to 
stand   in   a  cool   place   overnight.      It   was   then   firmly   squeezed 


COMPOSITION  OF  NATURAL  RAW-BEEF  JUICE. 


Method  of  Preparation, 

Water. 

Coagulable 
Protein. 

Eztrac- 
tivet. 

1.  Meat  from  round  slightly  broiled  and  pressed* 

2.  Meat  from  neck  slightly  broiled  and  pressed^ 

3.  Chopped  beef  heated  in  corked  bottle* 

4.  Lean   steak   slightly   broiled,   and    juice    ex- 

pressed with  lemon-squeezer  (i  lb.  yielded 
2^  oz.)» 

5.  I  lb.  beef  and  8  oz.  water  stood  on  ice  for  six 

hours ;     then    twisted     in    coarse    muslin 
(yield  rrS^oz.)* 

6.  4  oz.  minced  steak  soaked  for  an  hour  in  i  oz. 

¥?ater,  then  forcibly  expressed* 

88-1 
90 -1 
92-1 

929 

94 '9 
91  I 

6-97 
5-i8 

2-19 

2*90 

3*o 

5-1 

3-90 
3-56 
2-09 

3  •40 

I -go 
3'» 

in  muslin.  Four  and  a  half  ounces  of  juice  were  thus  obtained, 
containing  5^  per  cent,  of  coagulable  protein.  This  quantity  was 
retained  at  a  cost  of  5d,  In  this  table  there  is  exhibited  the  com- 
position of  most  of  the  beef-juices  met  with  in  the  market.  It 
will  be  observed  that  these  also  vary  considerably  in  composition. 

*  Bulletin  21,  United  States  Department  of  Agriculture,  p.  96. 

2  Holt's  '  Diseases  of  Children,'  1899,  p.  153. 

8  Cheadle's  '  Artificial  Feeding  of  Infants  '  (2nd  edit.),  p.  115, 


BEEF-JUICES    , 

COMPOSITION  OF  BEEF-JUICES.' 


i 

T3    3 

•0 
■3 

0  ~ 

-'2, 

9  ^ 
£0' 

'5 '3 

"> 

0 

1-. 

rt  0 

a 
«-. 

.S  o- 

£  c 

>M 

n 

0. 

B2 

0  '^ 

PQ 

m 

<2. 
0 

"   ?, 

-^ 

Water 

51-21 

59'i5 

42-91 

49'Si 

4487 

74-10 

53-01 

78-42 

23-07 

66-5 

2688 

Protein 

9 '65 

1 5 '45 

22"I3 

13-00 

38  01 

«-3 

7  "23 

13-32 

3r^8 

21-0 

11-77 

(oS3 

(5-23 

(6-87 

(371 

(3205 

(4-40 

coagu- 

coagu- 

as  albu- 

coagu- 

solu- 

coagu- 

lable) 

lable) 

min) 

lable) 

ble) 

lable) 

Extractives 

ii'i6 

i6-ss 

18-70 

8-IO 

— 

9'S4 

14-03 

o'SS 

13-44 

60 

0-55 

Non-  iiitro- 

— 

— 

— 

— 

— 

— 

20-76 

601 

6-75 

— 

59-56 

geno  us 

(carbo- 

matters 

hy- 
drates) 

Mineral 

10*84 

8-85 

16-26 

14'ao 

17-12 

7-51 

597 

I -60 

1327 

6-S 

1-34 

matter 

Of  the  various  ingredients,  the  coagulable  protein  is  the  most  im- 
portant, and,  as  the  amount  of  this  present  is  not  clearly  stated  in  some 
of  the  analyses,  I  have  estimated  the  quantity  contained  in  some  of 
these  preparations,  the  result  being  embodied  in  the  following  table: 

AMOUNT  OF  COAGULABLE  PROTEIN  IN  VARIOUS  BEEF-JUICES. 

In  I  Tea- 
spoonful. 
I -02  grammes. 
0-35  gramme. 
0-30      ,, 

030  .. 

0-24  ,, 

024  ,, 

022  ,, 

o'o6  ,, 

o  018  ,, 


•Bovinine'     ..         . 
*  Gamine  Lefrancq  ' 
Armour's  Beef-juice 
Wyeih's  Beef-juice 
Bovril  Meat-juice 
Brand's  Beef -juice 
'  Liquor  Carnis ' 
'  Taurine ' 
Valentine's  Meat-juice 


In  100  Parts 

by  Volume. 

17  per  cent. 

5-8 

„ 

5 

•• 

5 

•• 

4 

•• 

4 

•t 

3* 

ft 

I 

„ 

o'3 

., 

Bovinine  is  an  American  product  of  dark  brown  colour,  and  -when 
examined  with  a  spectroscope  shows  distinctly  the  presence  in  large 
amount  of  the  altered  colouring  matter  of  blood  (methaemoglobin). 
Indeed,  Professor  Chittenden,  -who  has  analyzed  it,^^  is  of  the  opinion 
that  it  is  prepared  largely  from  blood.     It  is  certainly  very  poor  in 

*  See  footnote  to  Table  of  Beef- Extracts. 

2  Analysis  by  Dr.  Candy  (unpublished).  For  other  analyses  of  Valentine's 
Meat-juice  see  Chittenden  {Medical  News,  Philadelphia,  1891,  Iviii.  716),  Food  and 
Sanitation  (April  22,  1893),  Leyden's  '  Handbuch  der  Ernahrungstherapie,' 
Forster  {Zeit.  fiir  Biologic,  1876,  xii.  475), 

3  Ihid.  *  Lancet  analysis  (1898,  i.  1407). 
»  Analysis  by  Dr.  Candy  (unpublished). 

•  Lancet  analysis  (supplied  by  makers). 

'  Attfield's  analysis  (supplied  by  makers).      •  Analysis  supplied  by  Company, 
'  Hehner's  analysis  (Allen,  loc.  cit.,  p.  309).  ^^  Analj'sis  by  makers. 

"  Analysis  by  Lancet,  1895,  ii.  267.  "  Analysis  by  Candy. 

*•  Medical  News,  Philadelphia,  1891,  Iviii.  716k 


102  FOOD  AND  DIETETICS 

extractives,  and,  in  my  opinion  at  least,  possesses  anything  but  an 
agreeable  flavour.  In  spite  of  its  cheapness,  therefore,  and  the 
comparatively  large  amount  of  protein  which  it  contains,  it  is  not 
a  preparation  to  be  recommended. 

'  Carnine  Lefrancq '  is  the  juice  of  raw  beef  concentrated  in  vacuo 
without  the  addition  of  any  preservative  other  than  sugar.  It 
contains  nearly  12  per  cent,  of  total  protein.  A  tablespoonful  of  it 
represents  the  amount  of  juice  in  100  grammes  of  raw  meat. 

Of  the  other  preparations,  Wyeth's,  Brand's,  and  the  Bovril  Com- 
pany's juices,  and  the  preparations  known  as  '  Taurine '  and  '  Liquor 
Carnis,'  all  exhibit,  on  examination,  the  appearances  characteristic 
of  the  unaltered  colouring  matter  of  blood,  and  may  rightly  be 
regarded  as  uncooked  juices.  The  amount  of  coagulable  protein 
which  they  contain  is,  however,  considerably  lower  than  that  in  the 
two  preparations  mentioned  above. 

It  may  be  admitted  that  many  of  these  preparations  contain  more 
protein  than  the  natural  or  home-made  beef-juice  already  described. 
It  by  no  means  follows,  however,  that  they  are  on  that  account  of 
higher  nutritive  value.  The  objections  urged  against  those  beef- 
extracts  which  also  pretend  to  be  foods  apply  here  with  full  force. 
A  patient  could  take  considerable  quantities  of  natural  raw-beef 
juice,  because  it  only  contains  salts  and  extractives  in  small 
amounts  ;  but  in  many  of  the  artificial  preparations  the  ratio  of 
these  ingredients  to  the  total  protein  is  so  high  that  they  could  only 
be  administered  in  very  moderate  quantity  without  running  the  risk 
of  exciting  diarrhoea  and  thirst.  That  no  raw-beef  juice,  whether 
natural  or  otherwise,  can  really  be  regarded  as  an  important  aid  to 
nutrition  is  evident  from  the  fact  that,  even  of  a  preparation  which 
contains  5  per  cent,  of  protein,  about  3  pints  would  be  needed  to 
supply  the  protein  required  by  an  invalid  daily.  The  administration 
of  such  a  quantity  is,  of  course,  impossible.  They  can  only  be 
of  some  slight  service  in  tiding  over  a  crisis  in  which  the  adminis- 
tration of  milk  is,  for  some  reason  or  another,  impossible.  As  an 
example,  one  might  mention  cases  of  vomiting  and  diarrhcea  in 
young  children.  One  must  be  careful  not  to  allow  oneself  to  be 
misled  by  the  examples  often  adduced  of  patients  who  have  lived  for 
several  days  'on  nothing  but  So-and-so's  beef-juice.'  Everyone 
knows  that,  provided  water  be  freely  supplied,  most  patients  are 
capable  of  living  on  nothing  but  their  own  tissues  for  a  surprisingly 
long  period.  In  most  of  these  instances  there  can  be  little  doubt 
that  the  patient's  own  fat,  and  not  the  beef- juice,  deserves  the  credit 
of  his  survival 


BEEF-JUICES  103 

Another  objection  to  the  use  of  artificial  beef-juices  is  their 
expense.  From  the  method  of  their  manufacture,  as  we  have 
seen,  this  is  almost  inevitable  ;  but  it  is  well  to  remember  that 
the  nutriment  which  they  contain  costs  many  times  more  than 
it  would  in  the  form  of  home-made  beef-juice,  and  in  one  case, 
at  any  rate,  fully  200  times  as  much.  It  is  really  pathetic  to  see 
poor  people  in  cases  of  illness  paying  large  sums  for  so  very  small 
a  return.  In  this  connection,  it  is  only  right  to  draw  attention 
to  the  very  great  value  of  egg-white  as  a  substitute  for  raw-beef 
juice.  Egg-white  contains  12  per  cent,  of  egg-albumin,  and  there 
is  no  reason  to  believe  that  egg-albumin  is  in  any  way  inferior  in 
nutritive  value  to  the  proteins  of  meat.  An  egg  yields  more  than 
an  ounce  of  white,  and  by  adding  to  this  twice  its  own  volume 
of  water,  and  straining  through  muslin,  one  obtains  3  ounces  of  a 
clear  solution  containing  4  per  cent,  of  coagulable  protein,  or  about 
as  much  as  an  average  specimen  of  commercial  beef-juice.  All  that 
remains  is  to  stir  into  this  a  little  Liebig's  extract,  dissolved  in 
a  teaspoonful  or  so  of  hot  water,  and  there  is  produced  3  ounces  of 
a  solution  which  can  hardly  be  distinguished  from  beef-juice,  at 
a  cost  of  little  more  than  a  penny,  or  twenty-four  times  cheaper  than 
most  commercial  juices.  This  preparation  can  be  used  under  the 
same  circumstances  as  beef-juice,  and  has  the  advantage  that  it  can 
be  given  practically  ad  libitum. 

We  may  next  turn  our  attention  to  ordinary  beef-tea.  Now,  the 
nutritive  value  of  beef-tea  depends  entirely  on  how  it  is  made.  If 
the  preparation  is  carried  out  in  such  a  way  as  to  insure  the 
extraction  of  some  at  least  of  the  protein  of  the  meat,  then  the 
beef-tea  will  have  nutritive  value;  on  the  other  hand,  if  it  is  so 
made  that  only  the  extractives  and  salts  of  the  meat  are  dissolved 
out,  then  it  can  never  hope  to  rank  as  a  food.  Applying  our  know- 
ledge of  the  chemistry  of  meat,  it  will  readily  be  apprehended  that 
the  temperature  at  which  the  tea  is  cooked  is  the  condition  which 
determines  whether  it  will  turn  out  to  be  a  food  or  not.  The  wrong 
way  to  make  beef-tea  is  to  bring  it  quickly  to  the  boil,  for  that 
coagulates  the  protein,  and  only  removes  the  extractives  and  salts  of 
the  meat.  Unfortunately,  much  of  the  beef-tea  which  is  presented 
to  sick  people  has  been  made  in  that  way,  and  hence  has  no  real 
value  as  a  food  ;  it  may  be  '  stimulating,'  or  anything  else  one 
pleases,  but  a  '  food '  it  never  can  be.  If,  however,  it  be  desired  to 
prepare  a  beef-tea  which  will  contain  real  nutriment,  one  should 
proceed  in  the  following  way  : 


104  FOOD  AND  DIETETICS 

Get  jome  good  lean  beef,  and  trim  oflf  with  a  knife  any  gristle  or 
fat  which  is  adhering  to  it,  and  then  scrape  the  meat  down  thoroughly 
with  the  back  of  the  knife  so  as  to  tear  it  into  shreds.  In  this  way 
all  the  fibres  of  the  meat  are  removed  from  the  connective  tissue 
which  holds  then  together ;  and  it  is  these  fibres  which  contain  the 
most  nourishing  part  of  the  meat.  Having  placed  the  fragments  of 
the  meat  in  a  jar,  add  to  them  some  water  and  mix  thoroughly. 
How  much  water  should  be  added  is  a  matter  of  taste.  Obviously, 
if  a  small  quantity  of  water  is  taken,  the  beef-tea  will  be  stronger 
than  if  much  is  used.  As  a  rule,  i  pint  of  cold  water  to  i  pound  of 
beef  is  the  proportion  recommended.  If  the  mixture  is  now  set  aside 
in  the  cold  for  some  time,  most  of  the  soluble  proteins  of  the  meat 
will  be  dissolved  out  along  with  the  extractives  and  salts.  A  little 
salt  is  sometimes  added  to  the  water  under  the  belief  that  its  solvent 
powers  are  thereby  increased.  It  is  doubtful,  however,  whether 
that  is  really  the  case.  By  the  end  of  half  an  hour  or  so  of 
standing  in  the  cold  one  has  got  what  is  practically  a  more  or  less 
dilute  raw-beef  juice.  The  jar  should  now  be  tightly  covered 
and  placed  in  a  saucepan  of  water,  and  the  latter  gradually  heated 
up.  The  temperature  for  at  least  the  first  hour  should  be  kept 
below  the  coagulating-point  (167°  F.),  and  from  time  to  time  the 
mixture  should  be  stirred  with  a  fork,  and  the  lumps  of  meat  squeezed 
against  the  sides  of  the  jar.  During  this  time  any  remaining  soluble 
protein  is  dissolved  out.  At  the  end  of  the  hour  the  tea  must  be 
cooked — i.e.,  its  raw  appearance  and  taste  taken  away  by  heating  it 
to  above  the  point  at  which  the  red  colouring  matter  is  coagulated. 
The  simplest  plan  is  to  bring  it  to  the  boil,  and  then  to  remove  it 
from  the  fire  immediately.  Prolonged  boiling  must  be  avoided,  as 
tending  to  render  the  coagulated  protein  hard  and  indigestible.  The 
tea  should  then  be  poured  off  from  the  residue  of  beef,  not  strained, 
the  lumps  of  beef  being  held  back  by  a  fork.i  When  this  has  been 
done,  the  residue  should  be  squeezed  very  hard  with  the  back  of  a 
spoon  in  a  coarse  strainer  or  sieve,  and  the  juice  which  comes  out 
added  to  the  tea.  The  latter  may  then  be  set  aside  to  cool.  When 
cold,  it  will  be  found  to  have  settled  into  two  layers  :  a  lower  layer 
composed  of  flocculent  particles,  and  an  upper  layer  of  brown  fluid. 
The  fat  on  the  top  should  be  removed  with  a  heated  spoon. 

The  reader's  particular  attention  must  now  be  directed  to  the 
two  layers  in  the  beef-tea.     The  lower,  flocculent  one  consists  of  the 

^  The  nutritive  value  of  the  preparation  can  be  immensely  increased  by  grating 
down  the  residue  of  the  meat  into  fine  particles  and  adding  these  to  the  tea.  This, 
however,  is  not  always  permissible. 


BEEF -TEA  105 

nutritive  part  of  tlie  preparation — namely,  the  protein.  It  has  been 
coagulated,  of  course,  by  bringing  the  tea  to  the  boiling-point,  but 
the  coagulation  has  occurred  in  the  form  of  very  fine  light  particles. 
Had  the  tea  been  passed  through  a  fine  strainer  or  through  muslin, 
as  is  sometimes  recommended,  these  particles  would  have  been  kept 
back,  and  the  value  of  the  tea  proportionately  lessened.  The  upper, 
or  fluid,  layer  corresponds  to  what  is  the  whole  tea  when  the  latter 
is  imperfectly  prepared ;  in  other  words,  it  consists  of  a  solution  of 
the  extractives  and  salts  of  the  meat. 

I  have  found  by  repeated  experiment  that  i  pound  of  lean  beef 
extracted  in  the  above  manner  with  a  pint  of  water  yields  28  ounces 
of  good  beef-tea,  containing  i^  per  cent,  of  protein,  and  about  the 
same  quantity  of  extractives.  Given  these  facts  as  to  the  com- 
position of  good  beef-tea,  what  is  one  to  say  of  its  nutritive  value  ? 
The  reply  is  obvious.  Seeing  that  the  preparation,  even  when 
carefully  made,  contains  only  about  i^  to  if  per  cent,  of  protein, 
it  can  never  be  regarded  as  an  important  aid  in  the  feeding  of  the 
sick.  If  one  swallows  a  pint  of  it  in  a  day,  he  has  only  consumed 
about  one-ninth  of  the  total  amount  of  protein  required  by  a  sick 
person.  Of  course,  beef-tea  may  be  given  with  some  advantage  to 
patients  who  are  confined  to  an  entirely  fluid  diet,  provided  the 
remaining  eight-ninths  of  the  protein  required  are  made  up  in  some 
other  form,  such  as  milk  or  white  of  egg. 

The  beef-tea  is  a  pleasant  change.  It  seems  to  promote  appetite 
to  some  extent,  and  its  extractives  possess,  as  we  have  seen,  a 
refreshing  influence.  It  may  be  objected  to  beef-tea  as  a  food  in 
comparison  with  raw-beef  juice,  that  its  protein  is  present  in  a 
coagulated  condition,  and  so  is  more  difficult  of  digestion  than 
the  uncoagulated  protein  of  raw-beef  juice.  I  question,  however, 
whether  this  objection  is  of  any  value.  Coagulated  protein  is  only 
difficult  of  digestion  when  present  in  comparatively  large  masses. 
Now,  in  beef-tea  the  protein  forms  very  fine  flakes,  which  offer  a 
large  surface  to  the  digestive  juices,  and  so  are  very  easily  dissolved, 
and  I  should  think  that  they  offer  no  appreciable  opposition  to  solution 
by  the  gastric  juice. 

It  is  sometimes  claimed  for  beef-tea  that  the  salts  which  it  contains 
are  of  value,  as  serving  to  replace  those  which  are  excreted  from  the 
body  in  large  quantities  in  some  diseases,  notably  in  fevers.  It  must 
be  questioned  whether  such  a  claim  has  any  real  value.  The  salts 
of  the  body  are  in  a  different  position  to  the  other  ingredients  which 
help  to  build  it  up.  When  they  have  served  their  purpose,  and  the 
tissue  into  whose  composition  they  entered  is  entirely  broken  down, 


io6  FOOD  AND  DIETETICS 

there  is  no  need  for  the  salts  to  be  excreted.  On  the  contrary, 
they  can  be  retained  in  the  body,  and  used  over  again  to  build  up 
new  tissue.  The  kidney  forms,  as  it  were,  a  kind  of  turnstile, 
through  which  all  the  soluble  constituents  of  the  body  must  pass 
on  their  way  out,  and  if  there  is  a  demand  for  salts  in  the  body,  the 
kidney  can  refuse  to  allow  these  to  escape.  There  is,  therefore,  no 
need  to  pass  in  new  salts  by  the  entrance  to  the  body  when  the  old 
ones  can  be  turned  back  at  the  exit.  In  other  words,  there  is  no 
justification  for  the  supply  of  saline-containing  beverages  in  fever.^ 

The  extractives  of  meat  are,  as  we  have  previously  seen,  excreted 
entirely  by  means  of  the  kidneys.  If  these  organs  be  acutely  inflamed, 
it  is  of  importance  to  diminish  their  work  as  much  as  possible,  and 
for  that  reason  beef-tea  and  beef-extracts  should  always  be  forbidden 
to  patients  who  are  suffering  from  acute  renal  disease. 

There  can  be  no  doubt  that  mistaken  ideas  as  to  the  nutritive 
value  of  beef-tea  are  still  very  prevalent,  especially  among  the 
laity,  in  spite  of  all  that  has  been  written  on  the  subject.  Fother- 
gill,  in  language  which  is  perhaps  somewhat  exaggerated,  says  on 
this  subject :  '  All  the  bloodshed  caused  by  the  warlike  ambition 
of  Napoleon  is  as  nothing  compared  to  the  myriads  of  persons  who 
have  sunk  into  their  graves  from  a  misplaced  confidence  in  the  food 
value  of  beef-tea.'  Jessop-  calculated  that  5-2  tons  of  beef  are  used 
in  Metropolitan  charitable  institutions  for  making  beef-tea  every 
week,  and  that  of  this  two- thirds  are  really  wasted. 

Much  of  this  waste  can  be  prevented  by  adding  to  the  beef-tea 
the  exhausted  fibre  of  the  meat,  care  being  first  taken  to  reduce  it 
to  a  state  of  fine  division.  This  is  what  King  Chambers  called 
whole  beef-tea.  Jessop  recommends  that  it  should  be  prepared  in 
hospitals  as  follows :  25  pounds  of  beef  are  boiled  with  100  pints  of 
water  for  three  hours,  then  mashed  up,  and  passed  through  a  colander 
to  reduce  it  to  a  fine  powder.  We  thus  get  meat  '  in  suspension,* 
and  3  to  4  ounces  of  it  can  be  given  every  three  or  four  hours, 
making  i|  pints  in  the  day,  which  is  ample. 

One  can  also  increase  the  nutritive  value  of  beef-tea  by  adding  to 
it  baked  flour  or  one  of  the  patent  cereal  foods,  or  by  stirring  in  a 
little  somatose,  nutrose,  aleuronat,  etc.  The  beef-tea  then  plays  the 
part  of  a  vehicle,  and  at  the  same  time  aids  the  digestion  of  the  food 
added  to  it. 

Beef-tea  is  now  prepared  on  a  large  scale  by  various  manufacturers 
as  a  substitute  for  the  domestic  article  to  be  used  in  hospitals  and 

*  For  a  possible  use  of  the  salts  of  beef-tea  in  promoting  osmosis^  see  p.  289. 

•  BriL  Mcd.Jfwm.,  X8S9.  ii.  463. 


strong  Beef-tea 

Vril  Albuminous  Beef- 

{Mason's). 

tea 

{Bovril  Co.). 

i!9  02 

8400 

2-47 

4-17 

6-86 

1017 

1-65 

1-66 

BEEF-TEA  107 

other  institutions.  Some  of  these  preparations  compare  very  favour- 
ably with  ordinary  beef-tea,  and  are  decidedly  more  economical  to 
use.     The  following  is  the  composition  of  some  of  them  : 

Fibrous  Beef-tea 
{Bra7id's). 
Water  ..         ..     83-21 
Extractives     ..       4-52 
Protein  ..     11 -40 

Mineral  matter       0*86 

Beef-powders. 

Ordinary  m^it  contains,  as  we  have  seen,  75  per  cent,  of  water, 
and  only  25  per  cent,  of  solids.  Any  successful  attempt  to  obtain 
the  nutritive  matter  of  meat  in  a  small  bulk  must  therefore  be  based 
upon  the  removal  of  part  at  least  of  the  water  which  it  contains. 
Now,  if  all  the  water  were  removed,  the  composition  of  the  resulting 
product  would  be  about  as  follows  : 

Protein  and  albuminoids  ..         ..         ..         ..     86  "S  per  cent. 

Extractives     ..  ..  ..         ..         ..         *.       7*8        „ 

Mineral  matter         ..         ..         ..         ..         ..       5*4       „ 

That  is  to  say,  it  would  contain  86*8  per  cent,  of  nutriment. 
Beef- powders  have  actually  been  prepared  in  this  way  by  simply 
drying  the  meat.  Of  these,  Pemmican  is  an  example,  the  nutritive 
value  of  which  has  been  further  raised  by  the  incorporation  of  40 
parts  of  fat  with  every  50  parts  of  powdered  meat,^  with  the  result 
that  it  is,  bulk  for  bulk,  about  the  most  nourishing  food  known.  A 
man  doing  hard  work — e.g.,  a  Canadian  hunter — can  eat  2  pounds  of 
it  a  day,  and  obtains  in  that  way  222  grammes  of  protein  and  445 
of  fat. 2 

Mosquera  Beef-meaP  is  a  powder  of  beef  which  has  been  partially 
digested  by  the  aid  of  the  ferment  contained  in  pineapple- juice, 
which  has  the  advantage  of  not  producing  bitter  by-products.  An 
analysis  of  it  by  Chittenden  shows  that  it  contains  90  per  cent, 
of  nutritive  matter,  of  which  fat  makes  up  13  per  cent,  and  protein 
77  per  cent.,  29  parts  of  the  latter  being  in  the  form  of  albumoses 
and  peptone.     It  is  therefore  a  preparation  of  high  nutritive  value. 

Somatose  is  a  completely  digested  meat-powder,  which  will  be 
described  later  (p.  563). 

The  objection  commonly  urged  against  meat-powders,  that  they 

*  Voit,  Zeitf  Biologic,  1889,  xxv.  232. 

'  Charque  is  a  similar  preparation  manufactured  in  various  parts  of  South 
America. 

'  Supplied  by  Parke,  Davis  and  Co. 


io8  FOOD  AND  DIETETICS 

are  difficult  of  digestion,  would  appear  to  be  unfounded.  Dujardin 
Beaumetz  had  a  large  experience  of  their  use,  and  strongly  re- 
commends them  as  not  only  readily  digested,  but  also  easily 
administered.  He  says  that  boiled  beef  can  be  easily  dried  on  a 
water-bath  and  ground  up  in  a  coffee-mill,  and  makes  an  excellent 
meat-powder.  It  is  most  conveniently  administered  when  stirred 
up  in  some  fluid  food,  such  as  chocolate  or  milk.  He  found  such 
powders  very  convenient  in  forced  feeding,  as  they  can  readily  be 
given  in  a  semi-fluid  form  through  a  nose-tube. 

Before  closing  this  chapter,  it  may  be  well  to  summarize  some  of 
the  conclusions  at  which  we  have  arrived  : 

1.  The  extractives  of  meat  are  incapable  either  of  building  up 
tissues  or  of  supplying  the  body  with  energy,  and  are  therefore  not 
foods.  On  the  other  hand,  there  is  some  reason  to  believe  that  they 
promote  nutrition  indirectly,  and  bring  about  a  better  utilization  of 
the  foods  with  which  they  are  given.  It  is  possible  that  they  act  in 
much  the  same  way  as  vitamines  (p.  i8). 

2.  They  do  not  act  as  cardiac  stimulants. 

3.  They  may  possibly  help  to  remove  fatigue  either  by  acting  on 
the  nervous  system  or  on  the  muscles  directly,  but  this  action  cannot 
yet  be  regarded  as  proved. 

4.  On  the  other  hand,  there  is  no  doubt  that  they  powerfully  aid 
digestion  by  calling  out  a  flow  of  gastric  juice,  whilst  their  pleasant 
flavour  enables  them  to  rouse  the  appetite.  They  are  therefore 
useful  additions  to  other  foods,  especially  where  the  appetite  and 
digestion  are  feeble,  and  may  also  be  taken  with  advantage  at  the 
beginning  of  a  meal,  as  in  the  form  of  soups. 

5.  If  taken  in  large  amount  they  excite  diarrhoea. 

6.  Ordinary  beef-extracts  {e.g.,  Liebig's)  possess  no  properties 
other  than  those  of  the  extractives  of  meat.  The  amount  of  protein 
which  they  contain  is  negligible. 

7.  Preparations,  such  as  Bovril  and  Oxo,  to  which  meat  fibre  has 
been  added,  may  theoretically  be  regarded  as  foods,  but  contain  far 
too  little  protein  to  admit  of  their  ever  being  able  to  contribute 
appreciably  to  nutrition. 

8.  Beef-juices  differ  from  beef-extracts  in  containmg  the  proteins 
of  meat  in  a  coagulable  form.  None  of  them,  however,  can  be 
taken  in  sufficiently  large  quantity  to  supply  much  protein  to  the 
body. 

9.  Natural  (home-made)  raw-beef  juice  contains  about  5  per  cent, 
of  coagulable  protein,  which  is  as  much  as  many  of  the  patent 
preparations,   whilst   its   comparative   poverty  in   extractives   and 


BEEF-POWDERS  109 

salts  enables  it  to  be  consumed  in  fairly  large  amounts.     It  is  also 
very  much  cheaper  than  the  patent  preparations. 

10.  A  solution  of  egg-white  flavoured  with  meat-extract  makes  a 
cheap  and  efficient  substitute  for  beef  juices. 

11.  Ordinary  beef-tea,  even  when  carefully  prepared,  does  not 
contain  more  than  2  per  cent,  of  nutritive  matters.  It  may  aid 
appetite  and  digestion,  but  is  of  very  little  value  as  a  food.  Its 
nutritive  qualities,  however,  can  be  greatly  ennanced  by  adding  to 
it  the  finely-powdered  fibre  of  the  meat  ('  whole  beef-tea  ').  It  is 
doubtful  if  the  salts  of  beef-tea  are  of  any  real  use. 

12.  The  only  means  of  getting  the  full  nutritive  value  of  meat  in 
small  bulk  is  by  the  use  of  meat-powders.  The  alleged  indiges- 
tibility  of  such  preparations  is  an  error,  and  they  may  frequently  be 
turned  to  good  account  in  feeding  the  sick. 


£xio] 


CHAPTER  VII 

MILK 

In  the  present  chapter  cow's  milk  alone  will  be  dealt  with.  We 
shall  reserve  till  later  the  study  of  human  milk  and  the  milk  of  some 
other  animals. 

I.  Chemical  Composition. 

As  regards  its  chemical  composition,  milk  occupies  an  almost 
unique  position  among  animal  foods,  for  it  contains  in  itself  repre- 
sentatives of  all  three  nutritive  constituents,  proteins,  carbohydrates, 
and  fat.     This  peculiarity  it  shares,  oddly  enough,  with  oysters. 

The  proteins  of  milk  constitute  only  about  3  per  cent,  of  its  total 
weight.  The  higher  estimates  which  used  to  be  current  are  now 
known  to  have  been  based  on  erroneous  analyses.  The  principal 
protein  is  the  substance  called  casein,  which  is  kept  in  a  state  ot 
more  or  less  perfect  solution  by  its  partnership  with  phosphate  of 
lime.  The  solution  is  not  clear,  but  opalescent,  and  is  the  chief 
cause  of  the  opaque  whiteness  of  milk. 

Chemists  have  still  much  to  learn  about  casein,  but  enough  is 
already  known  of  its  peculiarities  to  give  it  a  unique  place  among 
proteins.  To  some  of  these  peculiarities  allusion  will  be  made 
immediately,  while  the  consideration  of  others  may  conveniently  be 
deferred  until  we  come  to  the  study  of  human  milk. 

The  other  protein  of  milk  is  an  albumin  (lactalbumin),  which  is 
present  in  very  much  smaller  quantity  than  casein,  making  up  only 
about  one-seventh  of  the  total  protein  of  cow's  milk.  In  human  milk 
it  is  relatively  much  more  abundant. 

The  carbohydrate  constituent  of  milk  is  milk-sugar,  or  lactose,  which 
is  present  to  the  extent  of  from  4  to  5  per  cent.  It  differs  very  much 
from  cane-sugar,  and  in  nothing  more  than  in  its  comparative  free- 
dom from  sweetness.  In  a  substance  which  serves  as  a  food  rather 
than  a  condiment,  this  property  is  a  valuable  one.  Were  it  not  so, 
milk  would  pall  upon  the  taste  much  more  readily  than  it  does. 
Another  peculiarity  of  lactose  is  that  it  is  hardly  capable  of  being 


MILK  1X1 

fermented  by  yeasts.  As  a  consequence,  it  is  better  borne  than  other 
kinds  of  sugar  in  cases  of  advanced  dilatation  of  the  stomach  accom- 
panied by  fermentation.  On  the  other  hand,  it  is  readily  split  up  by 
certain  micro-organisms,  with  the  production  of  lactic  acid,  a  process 
which  occurs  in  the  souring  of  milk,  and  sometimes  also  in  the 
intestine,  producing  diarrhoea.  Many  cases  of  infantile  summer 
diarrhoea  are  brought  about  in  this  way. 

The  fat  of  milk  stands  intermediate  in  amount  between  the  protein 
and  sugar,  constituting  about  2,\  to  4  per  cent,  of  the  total  weight. 
It  is  interesting  to  note  that  the  amount  varies  considerably  with 
the  needs  of  the  animal  for  which  the  milk  is  designed.  In  the  milk 
of  animals  which  inhabit  cold  latitudes  the  percentage  of  fat  may  be 
very  much  higher  than  in  that  of  the  cow.  Whale's  milk,  for  example, 
contains  43  per  cent.^  The  meaning  of  this  adaptation  is  clear  when 
one  remembers  the  value  of  fat  as  a  body  fuel. 

Fat  exists  in  milk  in  the  form  of  an  emulsion  of  extraordinary 
perfection.  It  has  been  calculated  that  in  a  drop  of  milk  not  larger 
than  a  pin's  head  there  are  1,500,000  separate  fat  globules  (Roths- 
child). It  will  be  evident  thart  fat  so  finely  divided  as  this  must  be 
particularly  easy  of  digestion. 

When  milk  is  allowed  to  stand,  the  fat  globules  run  together,  and 
float  to  the  surface  as  cream.  If  this  be  removed,  skim  milk  is 
left ;  but  when  so  prepared  it  still  contains  some  fat,  perhaps  as  much 
as  I  per  cent.  If  the  cream  be  removed  by  means  of  a  centrifugal 
separator,  its  abstraction  is  much  more  complete  ;  for  separated  milk 
usually  contains  less  than  ^  per  cent,  of  fat.  Milk  so  prepared  should 
be  described  as  '  separated  milk.' 

Some  fuller  chemical  details  about  milk  fat  will  be  mentioned 
when  we  come  to  butter. 

Mineral  matter  is  fairly  abundant  in  milk,  forming  about  07  per 
cent.  Seeing  that  milk  is  the  sole  food  of  young  animals,  one  is  not 
surprised  to  learn  that  its  dififerent  mineral  ingredients  are  present  in 
exactly  the  same  proportions  as  in  the  body  of  the  particular  animal 
which  the  milk  is  designed  to  feed.  Now,  the  chief  tissues  which  a 
young  animal  has  to  build  up  are  muscle  and  bone.  For  the  former 
phosphate  of  potash,  and  for  the  latter  phosphate  of  lime,  is  required, 
and  both  of  these  salts  milk  contains  in  abundance.  To  the  rule  that 
the  mineral  ingredients  of  milk  correspond  proportionately  to  those 
in  the  body  of  a  young  animal  there  is  one  apparent  exception.  Iron 
is  an  essential  element  in  the  body,  and  especially  in  the  blood  ;  but 
iron  is  very  scantily  represented  in  milk.     Stockman  2  calculates  that 

*  Frankland,  Chemical  News,  1890,  Lxi.  63. 
"  Journ.  e/ Physiol.,  1S95,  xviii.  484. 


112  FOOD  AND  DIETETICS 

5  pints  of  milk  would  be  required  to  supply  the  amount  of  iron 
necessary  for  a  full-grown  man  every  day.  To  the  young  animal, 
however,  this  scarcity  of  iron  in  milk  is  a  matter  of  little  moment, 
for  it  enters  the  world  with  a  large  amount  of  iron  already  stored  up 
in  its  body,  which  it  has  obtained  from  the  blood  of  its  mother.  In 
the  adult,  on  the  other  hand,  the  lack  of  iron  means  a  deficiency  in 
the  supply  required  to  keep  the  blood  in  proper  condition  ;  and  for 
this  reason  persons  who  are  kept  for  a  long  time  on  a  purely  milk 
diet  are  apt  to  become  anaemic. 

There  remains  one  other  substance  which,  for  the  sake  of  conveni- 
ence, may  be  considered  under  the  mineral  ingredients  of  milk.  I 
refer  to  citric  acid.  It  is  rather  astonishing  to  find  this  substance  in 
milk  at  all,  and  yet  it  is  present  in  no  inconsiderable  amount ;  for  it 
has  been  calculated  that  a  good  cow  yields  as  much  citric  acid  in  the 
day  as  would  be  contained  in  two  or  three  lemons.* 

As  found  in  milk,  citric  acid  is  chiefly  combined  with  lime,  as 
citrate  of  calcium.  This  is  a  gritty  substance,  only  imperfectly 
soluble,  and  devoid  of  any  sour  taste.  The  solid  particles  sometimes 
met  with  in  condensed  milk  consist  chiefly  of  it.  The  possible  sig- 
nificance of  the  presence  of  citric  acid  in  milk  will  be  pointed  out 
when  we  come  to  the  subject  of  infant  feeding. 

Last,  but  not  least,  amongst  the  constituents  of  milk  is  water.  It 
forms  by  far  the  largest  proportion  of  the  milk  (87  to  88  per  cent.), 
and  holds  the  other  ingredients  in  more  or  less  complete  solution. 
It  is  owing  to  this  large  amount  of  water  that  milk  in  its  ordinary 
state  must  be  regarded  as  a  dilute  and  bulky  form  of  food. 

One  may  now  sum  up  what  has  been  stated  about  the  chemical 
composition  of  milk  in  the  following  table  : 

Cowposiiion  of  Cow*s  Milk. 


Fat         . .         .•     3|  to  4^  per  cent 
Mineral  matters  0-7      ,, 


Water  ..     87    to  88  per  cent. 

Protein         ..       3     ••    Si      n 
Sugar  ..      4    M    5        it 

Van  Slyke^  gives  the  average  of  5,500  analyses  of  milk   made  in 
America  as  follows : 


Water      ..  ..  8710  per  r-nt. 

Solids      ..  ..  1290        „ 

Casein      ..  ..       2 '50        „ 

Albumin  ..  ..      0-70        „ 


Fat..         ••         •.     3*90  per  cent. 
Sugar         ..         ..     5-10       „ 
Mineral  matters  ..     o  70       „ 


These  figures  merely  represent  the  average  composition  of  a  sample 
of  good  milk.      They  are  not  to  be  understood  to  apply  to  every 


>  Henkel,  Munch   Med.  Woch.,  1888,  xxxv.    328. 
•  New  York  Med.Journ.,  1907,  Ixxxv.  979. 


COMPOSITION  OF  MILK  113 

specimen  of  milk  one  may  encounter,  for  there  is  no  food  which 
varies  more  in  composition  than  milk.  Here  is  what  two  analytical 
writers  have  to  say  on  this  point : 

'  Milk,'  says  one,^  '  forms  in  many  cases  the  entire  diet  of  children 
and  invalids,  and  under  the  present  conditions  it  varies  so  enormously 
that  a  doctor,  in  prescribing  so  much  milk  per  day,  does  not  know 
within  30  per  cent,  how  much  nourishment  he  is  giving.' 

'Excepting  meats,'  says  the  other, 2  -there  is  probably  no  one 
article  of  food  which  is  liable  to  so  wide  a  variation  in  its  percentage 
composition  as  the  milk  supplied  to  the  consumer.  The  variations 
are  so  great,  in  fact,  as  to  make  it  entirely  possible  that  one  man 
may  pay  nearly  twice  as  much  as  his  neighbour  for  the  same  amount 
of  nutrients  when  both  buy  it  at  the  same  price  per  quart.' 

To  some  extent  these  variations  in  composition  are  unavoidable, 
depending  as  they  do  on  the  breed  and  age  of  cow  from  which 
the  milk  is  obtained,  on  the  way  in  which  the  cows  are  fed,  and  on 
the  period  which  has  elapsed  since  calving. 

In  the  mixed  milk  obtained  from  a  large  number  of  cows  these 
variations  must  to  a  considerable  extent  neutralize  one  another. 
Hence  it  is  that  the  total  milk  from  one  dairy  varies  less  in  composi- 
tion than  that  from  any  one  cow  in  it,  and  the  popular  prejudice  in 
favour  of  feeding  an  infant  on  milk  '  from  one  cow '  thus  rests  on  a 
false  basis. 

On  all  grounds,  both  commercial  and  dietetic,  it  would  be  well  to 
have  some  standard  by  which  to  judge  of  the  quality  of  the  milk  we 
buy,  and  by  which  to  regulate  the  price  we  should  pay  for  it.  Seeing 
that  it  is  the  solids  of  the  milk  that  we  want,  and  not  its  water,  and 
seeing  also  that  the  specific  gravity  of  a  fluid  depends  on  the 
amount  and  nature  of  the  solids  dissolved  in  it,  it  might  naturally 
be  supposed  that  the  specific  gravity  of  a  sample  of  milk  would  be  a 
guide  to  the  amount  of  solids  which  it  contains,  and  consequently  to 
its  nutritive  value  and  the  proper  price  to  pay  for  it.  This  would 
be  quite  true  were  it  not  that  fat  is  one  of  the  most  important  solids 
of  milk.  Now,  fat  is  lighter  than  water,  for  which  reason  the  cream 
rises  to  the  top.  A  specimen  of  milk  plus  its  cream  has  thus  an 
actually  lower  specific  gravity  than  one  from  which  the  cream  has 
been  removed  (skim  milk).  The  artful  milk-vendor  has  not  been 
slow  to  find  this  out,  and  accordingly  he  skims  his  milk,  and  then 

*  '  The  Analysis  of  Food  and  Drugs  '  (Pearmain  and  Moor),  1897.  Part  I., 'Milk,' 
p.  12. 

*  ♦  The  Use  of  Milk  as  Food,'  United  States  Department  of  Agriculture, 
Farmers'  Bulletin,  No.  363. 

Q 


114  FOOD  AND  DIETETICS 

lowers  the  specific  gravity  again  to  its  original  point  by  the  addition 
of  water.  Thus  he  effects  a  double  adulteration,  and  yet  leaves  the 
specific  gravity  as  it  was ;  consequently  the  specific  gravity  of  milk 
is  of  no  use  as  a  guide  to  its  composition. 

In  the  fat  of  milk,  however,  we  find  a  trustworthy  gauge  of  its 
quality.  Fat  is  not  only  in  itself  one  of  the  most  important  nutritive 
ingredients  of  the  milk,  but  a  milk  which  is  rich  in  cream  is  also 
rich  in  protein  and  sugar,  and  a  '  thin  '  milk  which  contains  little 
cream  is  always  poor  in  the  other  constituents  as  well.  Com- 
mercially, too,  there  is  good  reason  for  accepting  the  amount  of  fat 
as  the  standard  of  price,  for  the  fat  of  milk  is  its  most  expensive 
constituent.  The  last  point  in  favour  of  the  fat  standard  is  the 
practical  consideration  that  the  amount  of  fat  is  more  easily 
estimated  than  that  of  any  other  ingredient  of  the  milk. 

What  proportion  of  fat,  then,  should  be  insisted  upon  ?  On  this 
point,  unfortunately,  some  difference  of  opinion  exists.  Analysis  has 
clearly  shown  that  an  average  sample  of  good  milk  contains  at  least 
3 1  per  cent,  of  fat.  The  Society  of  Public  Analysts  allows  a  very 
liberal  margin  for  fluctuation  in  individual  samples,  and  regards  a 
specimen  of  milk  with  less  than  3  per  cent,  of  fat  as  adulterated. 
The  Inland  Revenue  Department  is  even  more  lenient,  and  takes 
2f  per  cent,  as  its  standard.  It  is  to  be  hoped  that  the  time  is  not 
far  off  when  the  public  authorities  will  insist  upon  a  uniform 
standard.^ 

From  what  has  been  said  of  the  chemical  composition  of  milk,  it 
might  naturally  be  regarded  as  a  fluid  form  of  food,  and  indeed  it  is 
often  one  of  the  chief  elements  in  a  so-called  '  fluid '  diet.  Strictly 
speaking,  however,  milk  is  not  a  fluid  food.  It  is  only  a  fluid  out- 
side the  body.  So  soon  as  milk  enters  the  stomach  it  undergoes  a 
change  by  which  it  very  soon  becomes  solid.  It  is  then  said  to  be 
coagulated  or  clotted.  This  coagulation  is  due  to  a  change  brought 
about  in  the  casein  by  the  ferment  called  '  rennin.'  The  exact 
nature  of  the  change  which  the  casein  undergoes  is  still  obscure, 
but  it  seems  to  be  split  up  by  the  rennin  and  then  to  become  solid  ; 
but  this  last  stage  only  occurs  if  salts  of  lime  are  present  in  the 
solution. 

The  coagulation  of  milk  is  what  occurs  in  the  making  of  junket. 

'  The  Departmental  Committee  on  Milk  and  Cream  appointed  by  the  Board  of 
Agriculture  in  January,  1900,  which  reported  in  January,  1901,  regards  3-25  per 
cent,  as  the  minimum  amount  of  fat  which  genuine  milk  may  contain.  Although 
milk  as  poor  as  this  may  sometimes  be  produced  by  cows  that  are  unsuitably  fed 
or  in  bad  health,  such  a  figure  seems  too  low  to  fix  as  a  standard  of  purity.  The 
consumer  has  a  nght  to  expect  a  natich  richer  fluid  when  he  buys  milk. 


COMPOSITION  OF  MILK  115 

In  that  process,  rennet  (a  preparation  of  the  ferment  rennin)  is  added 
to  the  milk,  which  is  then  set  aside  in  a  warm  place  until  it  is  solid. 
At  first  the  milk  forms  a  jelly,  but  by-and-by  the  curd  shrinks  and  a 
yellowish  fluid  is  squeezed  out  of  it,  which  is  the  '  whey.'  The 
rennet  which  is  used  in  this  operation  is  derived  from  the  lining 
membrane  of  the  stomach  of  the  calf,  but  exactly  the  same  ferment 
is  present  in  the  human  stomach,  and  it  is  important  to  remember 
that  all  raw  milk  is  converted  in  the  stomach  into  junket  very 
shortly  after  it  has  been  swallowed.  We  shall  return  in  greater 
detail  to  this  subject  when  we  come  to  the  digestion  of  milk. 

At  present  it  may  be  pointed  out  that  the  curd  of  milk  consists 
primarily  of  the  casein,  and  of  it  alone.  In  process  of  setting,  how- 
ever, the  casein  entangles  the  fat  of  the  milk  in  its  meshes,  so  that 
junket  consists  of  the  casein  along  with  the  fat. 

It  usually  also  contains  some  of  the  sugar  of  the  milk,  for  the 
whey  is  never  entirely  squeezed  out.  For  this  reason  junket  may 
have  to  be  avoided  by  diabetics. 

The  *  curdling '  of  milk  must  be  distinguished  clearly  from  the 
process  of  '  clotting '  just  described.  When  milk  '  curdles,'  its 
casein  is  simply  thrown  down  in  the  form  of  a  precipitate  without 
undergoing  further  change.  When  milk  '  clots,'  the  casein  undergoes 
profound  internal  alterations,  rendering  it  practically  a  new  substance 
with  new  characteristics.^ 

Curdling  is  due  to  the  production  of  lactic  acid  in  the  milk,  which 
turns  the  casein  out  of  its  partnership  with  lime  salts,  and  the  casein, 
being  in  itself  not  soluble,  then  falls  down  as  a  flocculent  precipitate. 

The  production  of  the  lactic  acid  is  due  to  a  splitting  up  of  milk- 
sugar  by  the  agency  of  certain  organisms  {Bacterium  lactis,  or  Bacillus 
acidi  lactici)  always  present  in  the  milk,  but  the  growth  of  which  is 
greatly  facilitated  by  certain  external  conditions,  of  which  warmth 

1  Many  English  physiologists  apply  the  name  •  caseinogen  '  to  the  chief  protein 
of  milk,  and  restrict  the  term  'casein  '  to  casemogen  which  has  been  altered  by 
coagulation.  This  nomenclature  has  the  advantage  of  emphasizing  the  difference 
between  the  products  of  curdling  and  clotting  above  described.  Adopting  it,  one 
would  say  that  when  milk  is  curdled  caseinogen  is  thrown  down  in  a  flocculent 
form  ;  when  milk  clots,  the  caseinogen  is  converted  into  casein.  Recently, 
however,  and  as  the  result  of  further  investigations  into  the  chemistry  of  milk,  a 
different  nomenclature  has  come  into  use.  According  to  this,  the  casein  of  normal 
milk  is  combined  with  calcium,  the  compound  being  described  as  '  calcium  casein.' 
Under  the  influence  of  rennin  this  is  converted  into  *  calcium  paracasein.'  When 
these  compounds  are  acted  upon  by  small  quantities  of  acids,  one  gets  the  casein 
or  paracasein  set  free,  but  if^  larger  quantities  of  acid  are  present,  the  lactate, 
hydrochloride,  or  other  acid  compound  of  casein  or  paracasein  is  formed.  The 
addition  of  lime-water  or  bicarbonate  of  soda  to  milk  converts  the  normal  calcium 
casein  into  basic  calcium  casein,  which  is  not  acted  upon  by  rennin.  (See  South- 
worth,  New  York  Medical  Record,  1905,  Ixvii.  321,  and  Cbafio,  Archives  of  Pediatrics, 
1907,  xxiv.,  8.) 


ii6  FOOD  AND  DIETETICS 

and  certain  electrical  conditions  of  the  atmosphere  appear  to  be  the 
chief.  ^  This  is  the  reason  for  the  readiness  with  which  milk  becomes 
sour  in  hot  and  thundery  weather. 

We  have  now  to  speak  of  the  effects  of  heating  upon  the  composi- 
tion of  milk. 

When  milk  is  boiled  in  an  open  pan  a  tough  '  skin '  forms  on  the  top. 
This  consists  to  some  extent  of  coagulated  lactalbumin,  but  partly 
also  of  dried  caseinogen  and  salts  of  lime  along  with  entangled  fat.^ 

The  boiling  of  the  milk,  possibly  by  the  driving  off  of  carbonic  acid 
gas,  seems  to  cause  some  of  the  casein  to  be  detached  from  the  lime 
salts  which  hold  it  in  solution,  and  it  then  becomes  entangled  with 
fat  and  floated  to  the  surface,  and  is  dried  by  evaporation  into  the 
'  skin '  with  which  everyone  is  familiar.^  If  the  skin  be  removed, 
another  straightway  appears,  and  by  continuing  the  process  the  milk 
undoubtedly  loses  some  of  its  nutritive  value.  The  loss  is  never 
great,  however,  for  loo  c.c.  of  milk,  if  boiled  for  a  quarter  of  an 
hour,  lose  at  most  only  0*273  gramme  of  protein.* 

Other  changes  observed  in  milk  heated  for  a  long  time  are  that  it 
becomes  of  a  somewhat  brownish  colour,  and  altered  taste.  The 
change  in  colour  seems  to  be  due  in  part  to  a  charring  of  the  sugar 
in  the  milk,  but  in  part  also  to  more  obscure  alterations.^  The 
change  in  taste  sets  in  quite  suddenly  when  a  temperature  of  70*  C. 
is  reached.  It  can  be  got  rid  of  to  a  large  extent  by  allowing  the 
milk  to  stand  for  some  time,  after  being  boiled,  and  then  straining  it. 

The  casein  also  seems  to  undergo  some  alteration  on  boiling,  for 
boiled  milk  coagulates  more  slowly  than  raw  milk.  To  this  point  we 
shall  return  later. 

By  far  the  most  important  result  of  boiling  milk  is  its  sterilization. 
The  significance  of  this  cannot  be  exaggerated.  The  bacteriology 
of  milk  has  been  the  subject  of  an  enormous  amount  of  research  in 
recent  years,  with  the  results  of  which  I  cannot  hope  to  deal  at  all 
adequately  here  ;^  but  this,  at  least,  one  may  say,  that  the  accusation 

^  The  influence  of  electrical  conditions  is  denied  by  many  authorities.  A  brief 
discussion  of  the  subject  will  be  found  in  the  Lancet  of  July  5,  1902. 

'^  See  Harris,  '  Chemistry  and  Coagulation  of  Milk, ' /oM^n.  of  Anat.  and  Physiol., 
1894-95,  N.S.,  ix.  188;  and  Solomin,  Archiv  f.  Hygiene,  1897,  xxviii.  43. 

'  There  is  still  an  absence  of  agreement  amongst  different  experimenters  as  to 
the  exact  way  in  which  the  'skin'  is  formed.  For  papers  on  the  subject,  see 
Jamison  and  Hertz  (Journ.  0/ Physiol.,  1901,  xxvii.  26)  and  Rettger  [Amer.  Journ. 
of  Physiol.,  1902,  vii.  325). 

*  Sofomin,  loc.  cit. 

*  See  Maly's  Jahres-Bericht  Thier-Chemie,  1895,  xxv.  210, 

*  For  a  useful  summary  of  the  subject,  see  Conn's  'Dairy  Bacteriology," 
Bulletin  25,  United  States  Department  of  Agriculture,  1895.  For  more  exhaustive 
information,  see  Swithinbank  *nd  Newman's  '  Bacteriology  of  Milk  '  (London  ; 
John  Murray.  1903). 


EFFECTS  OF  BOILING  MILK  117 

that  milk  is  a  not  infrequent  cause  of  disease  has  been  proved  up  to 
the  hilt. 

Milk,  as  it  comes  from  a  healthy  and  perfectly  clean  cow,  may  be 
regarded  as  a  sterile  fluid  ;  not  only  is  it  sterile,  it  seems  even  to  be 
possessed  of  feeble  germicidal  properties.  These  ideal  conditions, 
however,  are  difficult — one  had  almost  said  impossible — to  attain. 
Disease  in  cows,  especially  if  stall-fed,  either  general  and  constitu- 
tional (e.g.,  tuberculosis)  or  local  and  in  the  udders  {e.g.,  inflammation), 
occurs  very  frequently.  It  is  not  to  be  wondered  at,  therefore,  that 
milk  should  often  contain  the  germs  of  these  diseases.  Dr.  Eastes,^ 
for  example,  found  in  186  samples  of  milk  obtained  from  all  sources 
that  tubercle  bacilli  were  present  in  11,  and  the  organisms  of  pus  in 
47,  cases. 

Far  more  commonly,  however,  the  milk  gets  contaminated  either 
by  stagnation  in  the  udders  of  the  cow  or  from  the  introduction  into 
it  of  foreign  matter  after  it  is  withdrawn.  These  foreign  matters  are 
of  all  sorts,  but  are  chiefly  composed  of  manure.  It  was  once 
calculated  by  Dr.  Backhaus  that  the  inhabitants  of  Berlin  consume 
in  this  way  3  hundredweight  of  excrementitious  matters  per  diem.^ 
The  hands  of  the  dairyman  and  the  water  used  in  washing  the  cans 
are  other  possible  sources  of  infection. 

Once  arrived  in  the  milk,  the  germs  are  able  to  grow  and  multiply 
very  rapidly,  so  that  in  a  short  space  of  time,  especially  if  favoured 
by  warmth,  it  may  be  literally  swarming  with  them. 

Roughly  speaking,  the  micro-organisms  met  with  in  milk  may  be 
divided  into  two  classes — (i)  those  which  produce  souring,  (2)  patho- 
genic bacteria. 

The  former  are  probably  harmless,  unless  so  abundant  as  to 
produce  decomposition  of  the  milk  in  the  intestine,  when  diarrhoea 
may  be  set  up.  Their  chief  significance  lies  in  the  fact  that  owing 
to  their  presence  milk  cannot  be  kept  for  any  length  of  time  without 
turning  sour. 

The  pathogenic  bacteria  are  the  bearers  of  disease.  Amongst 
the  diseases  which  have  been  proved  to  be  conveyed  by  milk 
are  diphtheria,  typhoid  fever,  tuberculosis  (which  has  recently 
attracted  an  enormous  amount  of  attention),  scarlatina  and  perhaps 
cholera. 

The  disease  germs  are  more  easily  destroyed  than  those  which 
produce  souring.  A  temperature  of  75°  C.  (167"  F.)  maintained  for 
a  few  minutes  is  enough  to  kill  most  of  them.     If  the  milk  is  to  be 

»  '  The  Pathology  of  Milk.'  Brit.  Med.  Joum.,  1899,  ii.  134I« 

•  See  also  Conn,  op.  cit.,  p.  11. 


ii8  FOOD  AND  DIETETICS 

preserved  for  a  long  time,  however,  this  is  not  sufficient,  and  the 
temperature  must  be  raised  above  the  boiling-point  (i  io°  C. ;  230°  F.), 
and  kept  there  for  some  time.  This  is  the  process  of  sterilization. 
Sterilized  milk  is  now  prepared  on  the  large  scale  by  most  of  the 
leading  dairy  companies,  and  may  easily  be  made  at  home  by  the 
aid  of  Soxhlet's  or  Cathcart's  apparatus.^ 

.  Sterilization  is  undoubtedly  the  most  efficient  way  of  dealing  with 
the  germs  in  milk,  but  it  is  not  without  drawbacks.  It  alters  the 
taste  of  the  milk,  destroys  '  vitamines '  and  the  fine  emulsification 
of  the  fat,  coagulates  the  lactalbumin,  and  renders  the  casein  less 
easy  of  digestion. 

Efforts  have  been  made  to  overcome  these  disadvantages  by 
pasteurization.  This  consists  in  keeping  the  milk  at  a  temperature 
of  70°  C.  (158"  F.)  for  twenty  minutes  or  half  an  hour.  Of  this 
method,  however,  it  may  be  said  that,  though  it  kills  most  of  the 
disease  germs,  it  is  not  certain  to  destroy  the  tubercle  bacillus,  as 
well  as  some  bacteria  capable  of  causing  diarrhcea,  unless  it  be 
carried  out  very  carefully  and  in  closed  receptacles.^  Further,  milk 
so  treated  will  not  keep  more  than  three  or  four  days,  for  the  acid- 
forming  bacteria  are  still  present ;  nor  can  one  even  be  certain  of 
avoiding  alterations  in  the  taste,  for  that  change  sets  in,  as  we  have 
seen,  just  above  70°  C. 

For  ordinary  purposes  there  is  little  doubt  that  simply  boiling  the 
milk  for  a  few  minutes  is  the  simplest  and  most  satisfactory  method 
of  procedure.  If  carried  out  in  a  double  saucepan,  or  Aymard's 
boiler,  very  little  change  in  taste  of  the  milk  results,  especially  if  it 
be  rapidly  cooled  after  removal  from  the  fire,  and  subsequently 
strained,  as  already  described. 

There  is  every  reason  to  advocate  the  habitual  application  of  one 
or  other  of  these  methods  to  milk  before  it  is  consumed  as  food ;  and 
one  looks  forward  to  the  day  when  the  drinking  of  raw  milk  will  be 
considered  as  barbarous  a  custom  as  the  eating  of  raw  meat  is  at 
present. 

Various  methods  have  been  introduced  for  the  permanent  preser- 
vation of  milk  without  the  disadvantages  of  sterilization.  In  some 
of  these  the  milk  is  treated  with  peroxide  of  hydrogen.  Another 
process  consists  in  heating  the  milk  to  a  temperature  of  150°  F., 
after  which  it  is  charged  with  a  mixture  of  oxygen  and  carbonic 

1  For  much  practical  information  on  the  sterilization  of  milk,  see  Year-Book  of 
Treatment,  1897,  p.  149.  Cathcart's  apparatus  is  described  in  the  Brit.  Med.  Journ., 
1896,  i.  29.  It  has  the  advantages  of  being  cheap  and  easily  cleaned,  and  can 
be  obtained  from  Down,  St.  Thomas's  Street,  S.E. 

-  For  a  fuller  discussion  of  this  subject  than  is  possible  here,  see  Swithinbank 
and  Newman,  op.  cit. 


EFFECTS  OF  BOILING  MILK  119 

acid  gas.  It  is  then  heated  again  to  a  temperature  of  150**  F.,  after 
which,  it  is  stated,  the  milk  will  keep  good  for  an  indefinite  time, 
and  without  any  alteration  of  taste. 

In  what  is  known  as  the  *  White  Cross '  method  the  milk  is  first 
passed  through  a  centrifugal  separator,  which  removes  the  cream 
and  any  suspended  impurities.  The  skim  milk  is  then  heated  to  a 
temperature  of  140°  F.,  a  current  of  pure  air  being  passed  through 
it  at  the  same  time.  After  two  or  three  hours  it  is  reduced  to  one- 
fifth  of  its  volume.  Meantime  the  cream  is  also  pasteurized,  and  is 
then  added  again  to  the  milk,  and  the  whole  rapidly  cooled.  The 
final  mixture  has  only  one-fourth  the  bulk  of  the  original  milk.  It 
is  free  from  disease  germs,  will  keep  for  several  weeks,  and  when 
the  necessary  three  parts  of  water  are  added  the  product  cannot  be 
distinguished  from  good  fresh  milk. 

Milk  can  also  be  preserved  by  the  method  of  desiccation,  which 
consists  in  passing  it  in  a  thin  layer  between  two  heated  rollers,  or 
spraying  it  into  a  current  of  hot  air,  in  such  a  way  that  all  the  water 
is  immediately  evaporated,  and  a  fine  powder  results,  which  con- 
tains all  the  original  solids  of  the  milk  in  a  perfectly  soluble 
form.^  There  are  now  several  brands  of  dried  milk  on  the  market, 
and  the  product  has  no  doubt  a  great  future  before  it.  An 
analysis  of  New  Zealand  dried  milk  ('  Defiance '  brand)  gave 
the  following  result : 

Moisture     ..         ..         ..         ,.         .,  4*9  per  cent. 

Proteins 26*2        „ 

Fat 27-0        „ 

Milk  sugar 36-3        „ 

Mineral  matter     ..        ••        ••        ..      5*6        „ 


2.  Digestibility  of  Milk. 

It  might  be  supposed  that  milk,  being  a  fluid,  would  only  remain 
a  short  time  in  the  stomach,  and  rapidly  pass  on  into  the  intestine. 
But  we  have  seen  that  milk  is  only  a  fluid  outside  the  body  ;  when 
it  enters  the  stomach  it  sets  into  a  soHd  clot,  owing  to  the  action 

1  For  experiments  proving  the  sterility  of  dried  milk,  see  Hoffmann,  Arch.  f. 
Hyg;  1906,  lix.  216.  On  the  other  hand,  Delepine,  in  a  Report  to  the  Local 
Government  Board  (New  Series,  No.  97)  in  1914,  found  that  although  the 
number  of  bacteria  in  milk  is  greatly  reduced  by  drying,  the  powder  is  by 
no  means  sterile,  several  saprophytic  bacteria — e.g.,  B.  mesentericus — and  some 
pathogenic  types—^.^.,  the  bacillus  of  bovine  tuberculosis— surviving  the 
process. 


I30  FOOD  AND  DIETETICS 

upon  it  of  rennin.  Now,  the  gastric  juice  is  an  acid  fluid,  and  it  is 
at  first  sight  surprising  that  curdling  does  not  take  place  rather  than 
clotting.  That  this  does  not  happen  is  no  doubt  to  be  attributed  to 
the  fact  that  the  alkaline  salts  of  the  milk  neutralize  the  acid  first 
secreted  by  the  stomach,  and  give  the  rennin  time  to  act  before  the 
mixture  has  attained  an  acid  reaction. 

Whether  this  be  the  correct  explanation  or  not,  there  can  be  no 
doubt  of  the  fact  that  shortly  after  milk  has  been  swallowed  it  is 
converted  into  a  solid  mass.^ 

What  the  use  of  rennin  is  in  the  stomach  is  very  difficult  to  see. 
Certainly  clotting  is  not  a  necessary  preliminary  to  the  digestion  of 
milk,  for  the  latter  process  can  be  carried  on  artificially  outside  the 
body  to  its  most  advanced  stages,  with  the  milk  remaining  fluid 
all  the  time.  There  is  also  ample  provision  for  the  digestion  of 
milk  in  the  intestine,  and  if  it  be  so  prepared  that  clotting  in  the 
stomach  cannot  take  place,  its  ultimate  digestion  is  in  no  way 
interfered  with,  nor  is  it  found  that  patients  from  whom  the 
stomach  has  been  entirely  removed  for  disease  have  any  difficulty 
in  digesting  milk.  Rennin,  in  fact,  would  almost  appear  to  be  a 
superfluous  ingredient  in  the  gastric  juice,  and  its  presence  there 
is  rendered  all  the  more  inexplicable  by  the  fact  that  it  occurs  also 
in  such  situations  as  the  gizzards  of  fowls,  where  milk  is  never 
found  at  all. 

After  the  clot  of  casein  has  formed  in  the  stomach,  it  shrinks  into 
a  tough  and  leathery  mass,  which  offers  great  resistance  to  the 
digestive  efforts  of  the  organ.  Were  the  milk  merely  curdled,  the 
case  would  be  quite  different ;  for  the  particles  of  precipitated 
casein  are  dissolved  with  comparative  ease.-  This  is  one  of  the 
reasons  why  butter-milk  and  koumiss  are  often  found  to  be  more 
♦  digestible '  than  ordinary  milk. 

1  If  an  artificial  gastric  juice  containing  a  small  quantity  of  rennet  be  allowed 
to  drop  slowly  into  milk  at  the  body  temperature,  one  invariably  finds  that 
clotting  occurs  before  curdling.  Observations  on  dogs  by  Arthus  and  Pages 
{Mem.  de  la  Soc.  de  Biologic,  1891.  gth  series,  iii.,  131),  and  on  the  human  subject 
by  Beaumont,  Uffelmann  and  Reichmann,  have  shown  that  clotting  takes  place 
withen  a  quarter  of  an  hour  after  the  milk  has  been  swallowed. 

2  The  investigations  of  Van  Slyke  and  Hart  (see  footnote,  p.  115)  have  thrown 
a  new  light  on  the  digestion  of  casein.  Calcium  paracasein,  which  is  the  clot 
formed  by  rennin,  forms  a  flocculent  curd,  which  is  not  digested  by  pepsin 
unless  acid  be  present,  but  passes  almost  straight  into  the  intestine.  This 
happens  in  young  infants  whose  stomachs  secrete  little  or  no  hydrochloric 
acid.  If  acid  be  present,  paracasein  is  set  free,  and  forms  a  much  denser 
clot,  and  is  digested  by  pepsin.  If  hydrochloric  acid  be  in  excess,  paracasein 
hydrochloride  is  formed,  which  sets  into  a  still  tougher  curd,  and  takes 
still  longer  to  digest.  (See  Fowler,  '  Infant  Feeding,'  Oxford  Medical  Publica- 
tions, p.  20.) 


DIGESTIBILITY  OF  MILK  121 

If,  then,  we  wish  to  lighten  the  labours  of  the  stomach  in  the 
digestion  of  milk,  we  must  endeavour  so  to  arrange  matters  that 
the  milk  shall  not  form  a  tough  and  dense  clot  after  it  has  been 
swallowed. 

Now,  it  has  been  found  that  the  density  of  the  clot  which  milk 
forms  in  the  stomach  depends,  on  the  one  hand,  upon  the  amount  of 
casein  and  lime  salts  which  it  contains,  and,  on  the  other  hand,  upon 
the  degree  of  acidity  of  the  gastric  juice.  The  richer  the  milk  is  in 
casein  and  soluble  salts  of  lime,  and  the  more  acid  the  gastric  juice, 
the  tougher  is  the  clot.  On  the  other  hand,  by  reducing  the  pro- 
portion of  these  different  factors,  the  clotting  of  the  milk  can  either 
be  prevented  altogether  or  made  to  take  place  in  such  a  way  that 
the  clot  is  not  of  great  toughness  and  density. 

Obviously  mere  dilution  of  the  milk  with  water  lessens  the  pro- 
portion of  lime  salts  and  casein,  and  will  increase  its  digestibility. 
Dilution  with  lime-water  is  probably  not  more  efficacious  than 
dilution  with  ordinary  water,^  unless  it  be  in  virtue  of  its  slight 
alkalinity.  It  has  been  found,  however,  that  the  addition  of  even 
large  quantities  of  such  an  alkali  as  bicarbonate  of  soda  to  milk 
does  not  prevent  clotting  in  the  stomach. 

Barley-water  is  sometimes  recommended  as  a  diluent  instead  of 
ordinary  water.  Whilst  I  find  that  it  has  no  greater  power  of 
preventing  clotting  than  ordinary  water,  it  seems  to  some  extent, 
by  its  slight  degree  of  viscidity,  to  prevent  the  clot  from  shrinking 
into  a  tough  mass.  This  is  due  to  the  starch  which  it  contains. 
Three-quarters  per  cent,  is  the  best  strength  of  starch  in  the  milk 
mixture. 

Wright 2  has  shown  that  the  coagulation  of  milk  can  be  prevented 
by  the  addition  of  oae-fiftieth  of  its  volume  of  a  25  per  cent,  solution 
of  citrate  of  soda,  which  acts  by  converting  some  of  the  soluble 
lime  salts  into  insoluble  calcium  citrate.  Such  citrated  miUk  is 
employed  with  success  in  the  feeding  of  infants.  The  presence  of 
the  citrate  can  hardly  be  detected  by  the  palate,  and  milk  contains 
such  a  large  excess  of  lime  salts  that  the  removal  of  part  of  them  is 
no  disadvantage. 

*  Aeration  'of  the  milk  (such  as  can  be  effected  by  the  use  of  the 
'  Sparklets '  process)  is  another  important  means  of  combating 
density  of  clotting.     Milk  so  prepared  clots  rapidly,  but  the  clot 

*  See  'Observations  on  Milk  Coagulation  and  Digestion,'  by  F.  W.  White 
(Abstract  in  B'-nion  Med.  and  Surg.  Joitrn.,  1901,  cxlv.  13). 

2  '  On  the  Possible  Advantages  of  Employing  Decalcified  Milk  in  the  Feeding 
of  Infants  and  Invahds,'  Lancet,  1893,  ii.  194. 


122  FOOD  AND  DIETETICS 

is  very  friable.*  It  is  the  combination  of  aeration  and  dilution 
that  renders  '  milk-and-soda  '  so  much  more  digestible  than  plain 
milk. 

The  presence  of  much  acid,  as  has  been  mentioned,  favours  the 
retraction  of  the  clot  into  a  leathery  form.  Now,  the  degree  of 
acidity  of  the  gastric  juice  varies  in  different  individuals  within 
fairly  wide  limits,  and  that  may  explain  why  some  people  find  milk 
so  much  more  easy  to  digest  than  others.  For  this  reason,  too, 
milk  may  sometimes  disagree  in  those  cases  of  dyspepsia  which  are 
caused  by  over-acidity  of  the  gastric  juice. 

Another  method  of  preventing  the  formation  of  a  dense  clot  is  by 
mixing  the  milk  with  some  substance  which  will  get  in  between  the 
particles  of  casein,  as  it  were,  and  keep  them  apart,  so  that  they  do 
not  run  into  a  solid,  tough  mass,  but  form  a  more  or  less  spongy 
clot.  Mucilaginous  fluids,  such  as  barley-water,  act,  as  we  have 
seen,  in  this  fashion.  Thickening  the  milk  with  a  little  cornflour 
or  gruel  acts  similarly,  so  does  mixture  with  other  foods.  Milk  is 
thus  more  easily  digested  if  eaten  along  with  some  solid  food — e.g., 
a  biscuit — than  when  drunk  straight  off  by  itself. 

Boiled  milk  is  found  to  clot  more  slowly  both  in  vitvo  and  in  vivo, 
and  to  give  a  less  dense  clot,  than  raw  milk.^ 

The  exact  time  that  milk  remains  in  the  stomach  under  ordinary 
circumstances  has  been  determined  by  causing  a  healthy  man  to 
drink  a  definite  quantity  of  milk,  and  then  washing  out  the  stomach 
at  short  intervals.  In  this  way  it  has  been  found^  that  an  ordinary 
glass  of  milk  has  entirely  left  the  stomach  about  two  hours  after  it 
was  swallowed,  whilst  a  pint  of  milk  is  disposed  of  in  about  three 
and  a  half  hours.  By  a  similar  method  it  has  been  found*  that  the 
condition  of  the  milk  has  considerable  influence  upon  the  duration 
of  its  stay  in  the  stomach.     Thus: 

602  c.c,  (rather  more  than  a  pint)  of  raw  milk  have  left  the  stomach 

after 3|  hours 

,,        of  skimmed  milk  have  left  the  stomach  after  . .         ..         ••     3i     ,, 

"        °ll°''^ .  "  "  "  ^        " 

„        of  boiled  „  „  „  4       „ 

The  table  shows  that  sour  milk — e.g.,  butter-milk— is  the  most 
digestible   form.     The   explanation   of  this,   as   has   been   already 

^  Arthus  and  Pages,  loc.  cit. 

2  See  Arthus  and  Pages,  loc.  cit.,  and  Cautley,  'The  Feeding  of  Infants,' 
London,  1S97,  chap,  xiii.;  also  Brennemann,  yo!r/'«.  Amer.  Med.  Assoc,  1913, 
i-  575. 

3  See  Penzoldt,  Deut.  Archiv  f.  Klin.  Med.,  189^,  Bd.  Hii.,  p.  209  ;  and  Schiitz, 
Wiener  Klin.  iVocli.,  1896,  ix.  1116. 

*  Jessen,  Zcit.  /.  Biologie,  1883,  xix.  129. 


DIGESTIBILITY  OF  MILK  123 

pointed  out,  is  the  fineness  of  the  particles  of  the  precipitated  casein, 
which  enables  them  to  be  easily  dissolved.  The  table  also  confirms 
the  popular  belief  that  boiled  milk  is  somewhat  more  difficult  of 
digestion  than  raw  milk. 

The  difference,  however,  is  not  great,  nor  are  all  observers 
unanimous  on  the  matter.  Verhaegen,  for  instance,  finds^  that 
500  c.c.  of  boiled  milk  leave  the  stomach  in  two  and  a  half  hours, 
and  a  litre  in  three  and  a  half  hours,  and  Reichmann^  even  goes  so 
far  as  to  state  that  300  c.c.  of  boiled  milk  remain  one  hour  less  in 
the  stomach  than  a  similar  quantity  of  raw  milk  (three  hours  as  com- 
pared with  four).  This  result  he  attributes  to  the  boiled  milk  forming 
a  less  dense  clot.  It  must  also  be  remembered  that  boiled  milk  is 
more  concentrated  than  fresh  milk,  for  if  a  litre  of  milk  is  boiled  for 
fifteen  minutes  its  volume  is  diminished  by  a  quarter,  and  the  amount 
of  solid  matter  to  be  digested  is  proportionately  raised. 

It  will  be  obvious  from  these  conflicting  results  that  the  relative 
digestibility  of  boiled  and  unboiled  milk  cannot  yet  be  regarded  as 
finally  settled.  It  is  possible  that  idiosyncrasy  plays  a  considerable 
part  in  the  process. 

One  or  two  other  points  bearing  on  the  digestibility  of  milk  still 
remain  to  be  mentioned.  They  especially  affect  its  use  in  diseases 
of  the  stomach. 

In  the  first  place,  it  must  be  pointed  out  that,  thanks  to  its  alkaline 
salts,  and  to  the  large  proportion  of  protein  which  it  contains,  milk 
is  able  to  neutralize  a  very  considerable  quantity  of  acid."^  In  some 
diseases  of  the  stomach,  sul  i  as  ulceration,  in  which  it  is  desirable 
to  diminish  the  normal  acidity  of  the  gastric  juice,  this  property  of 
milk  makes  it  a  valuable  article  of  diet.  It  has  also  been  pointed 
out  by  Pawlow*  that,  in  proportion  to  the  amount  of  nitrogen  it 
contains,  milk  requires  for  its  digestion  a  weaker  gastric  juice  than 
any  other  food.  Hence,  the  secretory  work  required  of  the  stomach 
for  its  digestion  is  small,  and  this  is  another  point  in  its  favour  in 
many  diseased  conditions  of  the  stomach.  The  fat  which  milk 
contains  also  seems  to  exert  a  restraining  influence  on  the  amount 
of  gastric  juice  secreted.  It  may  be  for  this  reason  that  skim  milk 
is  more  easily  digested  by  invalids.     Lastly,  milk,  like  soup,  and  a 

^  '  Physiologic  et  Pathologic  de  la  Secretion  Gastrique,"  Paris,  1898,  p.  ii. 

'  '  Experimentelle  Untcrsuchungen  iiber  die  Milch  VerdauuHg  im  menschlichen 
Magen  '  {Zeit.  f.  Klin.  Med.,  1885,  ix.  565). 

2  Ten  c.c.  of  cow's  milk  can  neutralize  4  c.c.  of  decinormal  sulphuric  acid 
(Jager,  Maly's  Jahres-Bericht  Thier-Chemie,  1897,  xxvii.  271). 

*  •  Die  Arbeit  der  Verdauungsdriisen,'  p.  189. 


124  FOOD  AND  DIETETICS 

few  other  articles  of  diet,  seems  to  produce  a  secretion  of  gastric 
juice  independently  of  reflex  nervous  influences.  It  is  therefore  as 
sure  to  be  digested  if  poured  into  the  stomach  through  a  tube  as  if 
it  had  been  swallowed  in  the  ordinary  way.  This  is  by  no  means 
true  of  most  foods. 


3.  Absorption  of  Milk. 

When  it  has  left  the  stomach,  the  milk  reaches  the  intestine, 
where  its  digestion  is  completed  by  the  pancreatic  juice.  This 
juice  acts  very  powerfully  on  milk — more  so  than  the  gastric  juice. 
By  reason  of  this  provision  there  is  no  need  to  fear  that  milk  will 
escape  digestion,  even  if  it  be  so  prepared  that  it  does  not  remain  in 
the  stomach,  but  rapidly  passes  through  into  the  intestine. 

The  question  next  arises,  Is  the  digested  milk  completely  absorbed, 
or  does  it  leave  behind  any  considerable  amount  of  waste  residue  ? 
This  question  may  be  approached  by  investigating  the  degree  to 
which  the  different  constituents  of  milk  are  absorbed  when  isolated 
and  given  alone.  Proceeding  in  this  way,  it  has  been  found  that 
the  casein  of  milk  is  the  best  absorbed  of  proteins. 

It  is  absorbed  as  well  as,^  or  even  rather  better  than,'  the  protein 
of  meat,  whilst  the  fat  of  milk  enters  the  blood  quite  as  readily  as 
the  fat  of  beef.3  And  one  may  note  in  passing  the  interesting  fact 
that  the  fat  of  aerated  milk  is  absorbed  rather  better  than  that  of 
milk  which  has  not  been  so  treated.*  I  am  not  aware  of  any 
experiments  in  which  milk-sugar  was  given  by  itself,  but  it  is  usual 
to  assume  that  it  is  completely  absorbed. 

Considering  these  facts,  one  would  naturally  expect  to  find  that 
when  milk  was  given  as  a  whole  it  would  be  well  absorbed.  If  the 
different  components  of  it  are  so  completely  received  into  the  blood, 
surely  the  whole  of  them  given  together  will  enter  the  blood  with 
equal  ease  and  completeness  ?  But  yet  it  is  not  so.  Milk,  when 
giver  by  itself  as  the  exclusive  diet  of  an  adult,  is  not  very  well 
absorbed — worse,  indeed,  than  any  other  animal  food."  Even  under 
favourable  conditions,  only  about  90  per  cent,  of  the  available 
potential  energy  contained  in  the  milk  ever  reaches  the  blood.  The 
rest  escapes  from  the  body  as  unabsorbed  waste.     Thus,  if  2  litre? 

*  Salkovvski,  Berlin.  Klin.  Woch.,  1894,  xxxi.  1063. 
"  Marcuse,  PfiHger's  Archiv  ,  1896,  Ixiv.  223. 

'  'The  Use  of  Milk  as  Food,'  United  States  Department  of  Agriculture, 
Farmers'  Bulletin,  363,  p.  23. 

*  Jahres-Bericht  iiber  Thier-Ckemie,  1894,  xxiv.  46. 
»  Prausnitz,  Zeit.f.  Biologic,  1889,  xxv.  533. 


ABSORPTION  OF  MILK  125 

of  milk  are  taken  daily,  the  loss  of  dry  substance  amounts  to  5*7  to 
7-8  per  cent.  On  3  litres  the  waste  rises  to  10-2  to  11 '16  per  cent. 
(Rubner).  Prausnitz  found  a  loss  of  9  per  cent,  when  3  litres  were 
consumed  daily.  One  gramme  of  dried  milk  ought  to  yield  5733 
Calories.  Owing  to  defective  absorption,  it  only  yields  in  the  body 
5-067  Calories.  The  loss  affects  the  proteins  and  fat  about  equally, 
and,  in  a  notable  degree,  also  the  mineral  constituents  and  carbo- 
hydrates. 

These  results  apply  only  to  the  case  of  adults,  and  when  milk  is 
the  sole  food.  When  the  milk  forms  part  of  a  mixed  diet  it  is  much 
better  absorbed.  Thus,  in  an  average  of  ten  experiments  given  by 
Wait,  in  which  milk  was  the  exclusive  food,  only  92*1  per  cent,  of 
the  protein  and  86*3  per  cent,  of  the  carbohydrate  were  digested ; 
but  in  five  experiments  in  which  the  diet  consisted  of  bread  and  milk 
the  proportion  digested  rose  to  97" i  per  cent,  of  the  protein  and 
98*7  per  cent,  of  the  carbohydrates.  The  large  amount  of  water  which 
milk  contains  seems  to  interfere  with  the  action  of  the  intestines 
when  it  forms  the  sole  diet.^ 

It  is  an  interesting  and  remarkable  fact  that  milk  is  much  better 
absorbed  by  young  children  than  by  grown-up  persons.*  Thus,  even 
up  to  the  age  of  twelve  the  loss  of  nitrogen,  when  milk  is  given 
alone  is  only  4*4  per  cent.,  as  compared  with  more  than  ii  per  cent, 
in  the  adult.'  In  the  case  of  babies  absorption  is  even  more  complete, 
the  difference  being  to  a  large  extent  due  to  a  more  complete 
absorption  of  the  mineral  constituents,  the  reason  for  which  is  the 
greater  demand  for  lime  salts  in  the  infant.  This  reacts  favourably 
on  the  absorption  of  the  fat  of  the  milk,  for  unabsorbed  lime  salts 
are  apt  to  form  insoluble  soaps  with  the  fat,  and  so  hinder  its 
absorption. 

The  comparative  absorption  of  boiled  and  unboiled  milk  has  been  the 
subject  of  a  good  deal  of  experimental  investigation.  It  was  found 
that  dogs*  did  not  absorb  the  casein  of  boiled  milk  quite  so  well  as 
that  of  raw  milk,  but  the  absorption  of  fat  was  the  same  in  the  tv/o 
cases.  Another  observer,**  who  experimented  on  healthy  young 
men,  found   that   the   nitrogen   and   fat  of  raw   milk  were  better 

1  'Nutrition  Investigations  at  the  University  of  Tennessee,'  United  States 
Department  of  Agriculture,  Bull.  53,  p.  43. 

2  See  Rubner  and  Heuber  (Z«i.  /.  Biologic,  1898,  xxxvi.  i).  Uffelmann  (quoted 
by  Marcuse,  PJiiiger's  Archiv.  1896,  Ixiv.  223)  and  Camerer  {^eit.  /.  Biologic, 
1880,  xvi.  493). 

s  Prausnitz,  Zeit.f.  Biologic,  1889,  xxv.  533. 

*  Raudnitz,  Zeit.f.  Physiol.  Chem.,  1890,  xiv.  i. 

»  Vassilieff,  quoted  by  Cautley,  *  The  Feeding  of  Infants,'  1897,  P-  214. 


126  FOOD  AND  DIETETICS 

absorbed  than  the  same  ingredients  after  boiling ;  but  this  conclusion 
is  disputed  by  a  third. ^ 

It  has  further  been  found  in  the  case  of  infants  and  calves  that 
*  sterilized  milk  '  which  has  been  kept  at  or  above  the  boiling-point 
for  more  than  an  hour  is  absorbed  quite  as  well  as  milk  which  has 
merely  been  boiled  in  the  usual  way.^  Taking  the  whole  of  the 
evidence,  the  conclusion  seems  to  be  justified,  that  just  as  boiling 
does  not  appreciably  diminish  the  digestibility  of  milk  in  the  stomach, 
so  it  does  not  to  any  important  extent  interfere  with  its  absorption 
in  the  intestine.  One  need  have  no  fear,  therefore,  that  the  great 
advantages  of  boiling  are  purchased  at  the  cost  of  any  noteworthy 
diminution  of  digestibility  or  absorption.* 

Two  other  points  relating  to  the  behaviour  of  milk  in  the  intestine 
call  for  mention.  The  first  is  that  milk  seems  to  be  absorbed  with 
less  expenditure  of  energy — that  is  to  say,  with  less  wear  and  tear 
upon  the  part  of  the  intestine,  than  any  other  food.'*  This  no  doubt 
explains  in  part  the  great  value  of  milk-diet  in  many  intestinal 
diseases. 

The  other  point  is  that  milk  seems  to  exercise  a  restraining 
influence  upon  putrefactive  processes  in  the  intestine.  The  explana- 
tion of  this,  whether  it  is  to  be  attributed  to  the  casein  or  to  the 
influence  of  acids  produced  from  the  milk-sugar,  is  still  disputed, 
but  of  the  fact  there  appears  to  be  no  doubt.  There  is  reason  to 
believe  that  much  of  the  value  of  milk  diet  and  milk  '  cures '  in  many 
cases  is  due  to  the  diminished  absorption  of  putrefactive  products 
from  the  intestine  which  these  bring  about.* 

4.  Nutritive  Value  of  Milk. 

It  is  frequently  said  that  milk  is  a  perfect  food.  Now,  this  is  a 
high  claim,  and  can  only  be  justified  in  the  case  of  any  food  if  it 
fulfils  all  of  the  following  conditions  : 

1.  It  must  contain  all  the  nutritive  constituents  required  by  the 
body :  proteins,  fats,  carbohydrates,  mineral  matter  and  water. 

2.  It  must  contain  these  in  their  proper  relative  proportions. 

3.  It  must  contain  the  total  amount  of  nourishment  required 
daily  in  a  moderate  compass. 

'  Gaschibowsky,  Maly's  Jahres-Btricht  Thier-Chemle,  1894,  xxiv.  502. 

*  See  Bendix,  Jahrb.  /.  Kinderheilk.,  1S94,  xxxviii.  393  ;  Cautley,  op.  cit.,  p.  215  ; 
and  Weber,  Bull,  de  la  Soc.  Med.  Prat,  de  Paris,  1892,  p.  77. 

'  Experiments  on  young  rats  {Journ.  of  Hygiene,  1909,  ix.  233)  showed  no 
diminution  in  the  nutritive  value  of  milk  when  boiled,  or  even  when  evaporated 
and  dried. 

*  Pawlow,  •  Die  Arbeit  der  Verdauungsdriisen,'  p.  189. 

*  The  alterations  in  the  urine  of  patients  on  exclusively  milk  diet  pointed  out  by 
Weir  Mitchell  ('  Fat  and  Blood,'  p.  114)  are  also  to  be  explained  by  a  diminution 
of  intestinal  putrefaction. 


NUTRITIVE  VALUE  OF  MILK 


127 


4.  The  nutritive  elements  must  be  capable  of  easy  absorption, 
and  yet  leave  a  certain  bulk  of  unabsorbed  matter  to  act  as  intestinal 
ballast. 

5.  It  must  be  obtainable  at  a  moderate  cost. 

On  examining  the  claims  of  milk  to  be  regarded  as  a  perfect  food, 
one  finds  that  it  only  conforms  to  the  first  of  the  conditions  above 
laid  down. 

It  does  indeed  contain  representatives  of  all  the  nutritive  con- 
stituents required  by  the  body,  but  it  does  not  contain  them  in  proper 
relative  proportion.  Relatively  it  is  too  rich  in  protein  and  fat,  and 
too  poor  in  carbohydrate,  to  be  a  perfect  food.  In  order  to  obtain 
the  requisite  3,000  Calories  of  energy  daily,  one  would  require  to  con- 
sume about  8  pints  of  milk,  and  that  would  contain  about  140  grammes 
of  protein,  which  is  considerably  more  than  is  necessary.  An 
excess  of  protein  and  fat  is  essential  in  the  case  of  infants,  where  the 
body  substance  is  being  added  to  by  growth  and  where  a  large 
supply  of  fuel  is  needed,  but  it  is  not  necessary  for  adults.  Milk, 
in  fact,  is  a  food  for  babes,  not  for  men. 

Further,  milk  is  much  too  bulky  to  be  a  perfect  food.  For  the 
complete  nutrition  of  a  healthy  man  doing  a  moderate  amount  of 
muscular  work  about  8  pints  of 
milk  would  be  required  daily. 
That  means  that  a  tumblerful 
of  milk  must  be  swallowed 
every  hour  of  the  working  day. 
This  is  an  inconveniently  large 
quantity,  and  necessitates  the 
burdening  of  the  system  with  a 
considerable  surplus  of  water. 

In  the  matter  of  ballast,  also, 
milk  is  deficient.  It  is  true 
that  it  is  by  no  means  com- 
pletely absorbed,  but  the  residue 
is  not  bulky  enough  to  supply  a 
sufficient  stimulus  to  peristalsis, 
and  it  is  well  known  to  be  a 
constipating  food. 

Lastly,  milk  is  too  expensive 
to  be  a  perfect  food.  To  live 
on  it   alone  would   cost  about 

IS.  6d.  a  day.     An  ordinary  mixed  diet  can  be  obtained  for  less  than 
a  sbilling.  % 


LOSS. 
0  58Gri 


Fig, 


0  49Oiitt» 


uii-^ — .  0.84QMWS 

MAT  2Grpi| 

Actual  Composition  of  a 
tumblbrfdl  of  ordinary  milk,  and 
i'ercentage  of  loss  from  non-ab- 
sorption. 


128 


FOOD  AND  DIETETICS 


We  conclude,  then,  that  milk  is  by  no  means  a  perfect  food.  On 
the  other  hand,  it  is  admirably  fitted  to  supplement  the  deficiencies 
of  other  articles  of  diet.  It  is  one  of  the  cheapest  sources  of  animal 
protein.  Eight  pennyworths  of  whole  milk  yield  as  much  protein  as 
ten  pennyworths  of  beef.  But  milk  has  the  advantage  over  beef  of 
containing  a  considerable  amount  of  carbohydrate  in  addition  to 
its  protein  and  fat,  with  the  result  that  a  quart  of  good  milk  is 
nearly  equal  in  nutritive  value  to  a  pound  of  beef-steak.  Skim  milk 
is  an  even  cheaper  source  from  which  to  supplement  any  lack  of 
protein  in  the  diet,  for  it  supplies  that  constituent  in  a  cheaper  form 
than  any  other  animal  food  except  salt  fish.  Its  great  value  in  the 
dietary  of  persons  to  whom  economy  is  of  importance  cannot  be 
overestimated.  It  is  in  carbohydrate  that  milk  is  specially  deficient. 
Hence  it  should  be  used  chiefly  in  conjunction  with  other  foods  rich 
in  that  ingredient.  Such  a  food  is  bread.  An  interesting  practical 
illustration  of  the  great  nutritive  and  economic  value  of  a  combina- 
tion of  skim  milk  and  bread  is  furnished  by  the  following  comparison 
of  a  lunch  composed  solely  of  these  ingredients  with  an  ordinary 
lunch,  such  as  might  be  supplied  at  a  restaurant.* 


Lunch  op  Skim  Milk  and  Brbad. 

Restaurant  Lunch. 

In- 
gredients. 

Amount. 

CoSL 

Fuel 
Value  in 
Calories. 

In- 
gredients. 

Amount. 

Cost. 

Fuel 
Value  in 
Calories. 

Bread  . . 
Skim 
milk 

lO  oz. 
I  pint 

lid. 
4d- 

755 
170 

Soup    . . 
Beef     . . 
Potatoes 
Turnips 
Bread  . . 
Butter 
Coffee: 
Milk 
Sugar 

8  oz. 

2     „ 
2     >• 
t     .. 
4    .. 

i.. 
i.. 

75 
275 
100 

15 
300 
100 

20 

55 

Totals 

2d. 

925 

Totals 

Sd. 

940 

It  vnll  be  observed  that  bread  and  milk  furnished  at  a  cost  of 
2d.  almost  as  many  Calories  {i^.,  heat  and  energy)  as  were  obtained 
from  the  restaurant  lunch  at  four  times  that  price. 

The  claims  of  skim  milk  to  be  regarded  as  a  valuable  source  of 
food  are  thus  fully  justified,  and  should  be  carefully  considered  by 
all  who  are  responsible  for  drawing  up  an  ample  and  economical 
dietary  for  large  numbers  of  persons,  such,  for  example,  as  the 
inmates  of  public  institutions. 

Unfortunately,  the   prevailing  tendency  is   to  regard   milk   as  a 

>  From  '  Milk  as  Food  '  (original  edition),  United  States  Department  of  Agrl- 
calture,  Farmers'  Bulletin,  74. 


NUTRITIVE  VALUE  OF  MILK  129 

beverage  rather  than  as  a  food.  This  is  a  great  mistake,  in  proof  of 
which  one  cannot  do  better  than  quote  an  extract  from  the  valuable 
pamphlet  on  '  The  Use  of  Milk  as  Food '  issued  by  the  United  States 
Department  of  Agriculture,  to  which  reference  has  already  been  fre- 
quently made.  The  following  extract  states  succinctly  the  advantages 
which  are  obtained  from  the  liberal  use  of  milk  in  a  dietary  : 

*  A  very  interesting  experiment  was  recently  made  at  the 
University  of  Maine,  in  co-operation  with  this  department,  in  which 
the  effect  of  a  limited  and  an  unlimited  amount  of  milk  was  tried  at  the 
University  boarding-house  or  *'  commons."  From  these  studies  the 
following  conclusions  were  drawn  :  (i)  The  dietaries  in  which  milk 
was  more  abundantly  supplied  were  somewhat  less  costly  than  the 
others,  and  at  the  same  time  were  fully  as  acceptable ;  (2)  the  in- 
creased consumption  of  milk  had  the  effect  of  materially  increasing 
the  proportion  of  protein  in  the  diet ;  (3)  the  milk  actually  supplied 
the  place  of  other  food  materials,  and  did  not,  as  many  suppose, 
simply  furnish  an  additional  amount  of  food  without  diminishing  the 
quantity  of  other  materials ;  (4)  the  results  indicate  that  milk  should 
not  be  regarded  as  a  Itixury,  but  as  an  economical  article  of  diet 
which  families  of  moderate  income  may  freely  purchase  as  a  probable 
means  of  improving  the  character  of  the  diet  and  of  cheapening  the 
cost  of  the  supply  of  animal  foods.* 

As  an  article  of  diet  in  disease  milk  occupies  a  unique  position. 
No  single  food,  it  may  safely  be  said,  is  of  so  much  value.  The 
drawbacks  to  its  exclusive  use  in  health,  which  it  was  one's  duty  to 
point  out  above,  are  now  of  no  account,  or  are  even  converted  into 
advantages.  The  use  of  milk  in  the  dietary  of  different  diseases  will 
be  considered  in  detail  in  a  subsequent  chapter,  but  some  of  its 
general  advantages  may  be  mentioned  in  this  place. 

Being  in  a  fluid  form,  it  is  easily  swallowed.  This  is  a  great  gain 
in  the  case  of  exhausted  patients.  For  the  same  reason,  the  quantity 
given  can  be  very  simply  regulated  and  measured.  Its  fluid  form 
also  enables  it  to  be  used  as  a  substitute  for  other  beverages,  and  a 
glass  of  milk  with  each  meal  is  one  of  the  simplest  prescriptions  for 
increasing  the  amount  of  nourishment  a  patient  is  talcing.  It  is 
often  recommended  to  people  who  require  to  be  '  fed  up.' 

The  amount  of  water  which  it  contains  causes  milk  to  be  a  means 
of  quenching  thirst  as  well  as  of  supplying  food,  and  makes  it 
grateful  to  feverish  patients.  In  virtue  of  the  same  property  it  can 
act  as  a  diuretic,  a  function  which  is  of  great  help  in  the  treatment  of 
some  forms  of  heart  disease  with  oedema,  in  cases  of  renal  disease, 
and  in  all  inflammatory  affections  of  the  urinary  passages. 

9 


130  FOOD  AND  DIETETICS 

The  bulkiness  which  its  richness  in  water  entails  is  no  serious 
drawback  in  most  cases  of  illness.  A  patient  who  is  at  rest  and 
warm  in  bed  requires  much  less  nourishment  than  an  active  man, 
and  will  often  gain  weight  on  3  or  4  pints  of  milk  a  day,  although 
more  than  twice  that  quantity  is  requisite  for  the  needs  of  health.^ 

In  addition  to  this,  there  is  reason  to  believe  that  concentrated 
foods  are  not  well  borne  in  cases  of  severe  disease,  and  that  a 
moderate  degree  of  dilution  is  an  advantage  rather  than  otherwise. 
The  peculiar  behaviour  of  milk  in  the  stomach  and  intestine,  the 
fact  that  it  is  digested  with  little  secretory  effort  and  absorbed  with 
but  a  moderate  expenditure  of  energy,  and  that  its  presence  tends  to 
restrain  the  development  of  intestinal  putrefaction,  have  been  already 
referred  to,  and  mark  milk  out  as  a  food  of  special  value  in  gastro- 
intestinal disorders.  To  these  advantages  should  be  added  the  facts 
already  mentioned,  that,  though  rich  in  protein,  milk  is  devoid  of 
such  *  stimulating '  substances  as  are  found  in  meat,  and  that  its  use 
is  attended  by  a  diminution  in  the  excretion  of  uric  acid. 

It  is  probably  to  a  combination  of  these  advantages  that  *  milk 
diet '  and  '  milk  cures '  owe  the  benefits  obtained  from  their  use.- 

From  an  early  age  milk  was  regarded  as  a  sovereign  remedy  in 
many  diseases.  By  Hippocrates,  Celsus,  and  Galen  it  was  recom- 
mended in  phthisis,  and  especially  in  gout.  Amongst  medieval 
writers  Van  Swieten  and  Hoffmann  also  recognised  its  great  virtues, 
whilst  its  most  strenuous  advocate  in  modern  times  has  been 
Dr.  Karell,  late  physician  to  the  Czar  of  Russia.^  Donkin  also  did 
much  to  make  its  virtues  known,  while  in  later  years  it  has  attained 
prominence  as  an  important  part  of  the  '  Weir- Mitchell  treatment.' 

Karell  recommends  a  trial  of  the  milk  cure  in  dropsies,  asthma, 
neuralgias  of  intestinal  origin,  cases  of  '  malnutrition,'  and  some 
diseases  of  the  liver.  Its  use  in  diabetes,  obesity,  and  some  forms 
of  valvular  heart  disease  will  be  considered  later. 

The  directions  given  by  those  who  have  had  most  experience  of 
its  use  are  that  the  milk  should  be  skimmed,  and  should  be  given 
quite  fresh,  not  boiled.     •  A  temperature  of  212*  F.,  I  feel  assured/ 

*  See  Horton  Smith,  Joum.  of  Physiol.,  1891,  xii.  42,  and  Prausnitz,  Zeit.  f. 
Biologie,  1889,  xxv.  533  ;  also  Weir  Mitchell,  'Fat  and  Blood,'  chap.  viii. 

*  It  is  now  believed  that  some,  at  least,  of  the  advantages  of  an  exclusive  milk 
diet  in  disease  are  to  be  attributed  to  a  limitation  of  the  intake  of  salt  which  such 
a  diet  entails.  In  other  words,  it  is  a  '  de-chlorinating '  diet.  (See  '  Salt-Free 
Diet,'  p.  556.) 

'  '  On  the  Milk  Cure,'  Edin.  Med.  Joum.,  1866,  xii.  97.    An  interesting  historical 
resume  of  the  therapeutic  uses  of  milk  will  be  found  in  Donkin's  '  Diabetes  and, 
Bright's  Disease.'  1871,  chap.  i. 


MILK  CURES  131 

says  Donkin,  *  either  seriously  impairs  or  altogether  destroys  its 
therapeutic  energy,  possibly  by  altering  the  molecular  constitution 
of  the  casein  or  by  destroying  some  vital  property  with  which  it  is 
endowed.* 

At  first  not  more  than  2  to  6  ounces  should  be  given,  at  regular 
intervals  of  three  or  four  hours,  none  being  given  at  4  a.m.  The 
milk  should  be  sipped,  not  swallowed  at  a  draught,  and  may  be  given 
either  warm  or  cold  as  preferred.  By  the  third  day  the  quantity  at 
each  feed  may  be  increased  to  half  a  pint,  so  that  in  all  3  pints  are 
consumed.  By  the  end  of  a  week  the  total  may  have  risen  to 
6  pints  per  day,  but  one  should  not  attempt  to  go  much  above  this. 
The  '  cure  '  should  last  five  or  six  weeks. 

Amongst  the  *  normal '  symptoms  exhibited  by  a  patient  on  a 
purely  milk  diet  are  a  certain  amount  of  drowsiness  and  the  passage 
of  a  large  quantity  of  urine  of  a  pale  greenish  colour,  which  gives 
no  brownish-red  ring  on  the  addition  of  nitric  acid.  The  tongue  is 
covered  with  a  white  fur,  and  there  is  often  a  sweetish  taste  in  the 
mouth.  A  moderate  degree  of  constipation  is  a  good  sign,  orange- 
coloured  stools  being  passed  at  intervals  of  two  or  three  days.  If 
this  symptom  becomes  too  pronounced,  a  little  coffee  or  caramel  may 
be  added  to  the  morning's  milk,  or  a  little  stewed  fruit  may  be 
taken  once  a  day.     Diarrhoea  is  due  to  the  use  of  a  too  rich  milk. 

The  objections,  frequently  of  a  fanciful  nature,  which  are  often 
urged  by  the  patient  at  the  beginning  of  such  a  regimen  must  be 
overcome  by  firmness  and  tact,  while  in  some  cases  the  addition  of 
a  little  tea,  coffee,  caramel,  or  salt  may  make  the  milk  more  endur- 
able. 


C^3»] 


CHAPTER  Vni 
FOODS  DEBIVED  FROM  MILS 

Whey — Cream — Butter — Butter-milk  —  Koumiss    and    Kephir— 
Casein  preparations. 

Whey. 

Wk  have  already  learnt  that  whey  is  the  fluid  which  exudes  from 
clotted  milk.  It  is  best  prepared  by  adding  to  30  ounces  of  milk 
heated  to  104"  F.  two  teaspoonfuls  of  rennet,  and  setting  aside  in  a 
warm  place  till  clotting  has  occurred.  The  clot  must  then  be 
broken  up  very  thoroughly  by  stirring,  and  the  whole  strained 
through  muslin.  About  22  ounces  of  whey  should  be  obtained  with 
(approximately)  the  following  composition : 


Water      ..         ..     93-64  per  cent. 
Protein    ..         ..      0-82       ,, 
Fat  ..         ..       0-24      ,, 


Sugar      ..         ..       4"65  per  cent. 
Mineral  matter  . .       065       „ 


Whey  can  also  be  made  by  precipitating  the  casein  by  means  of  an 
acid — e.g.,  a  sour  wine.  It  is  in  this  fashion  that  white  wine  whey 
is  prepared.  Alum  whey  is  a  similar  product.  A  desiccated  whey 
is  made  under  the  name  of  Secwa}  It  contains  all  the  constituents 
of  whey  in  a  sterile  and  soluble  form,  and  is  a  very  convenient  and 
useful  preparation. 

Whey,  as  its  composition  indicates,  is  a  fluid  of  but  small  nutritive 
value.  It  hardly  ever  enters  into  an  ordinary  diet,  but  is  often  an 
aid  in  the  feeding  of  infants.^  It  has  slight  laxative  properties,  and 
should  be  avoided  when  there .  is  any  tendency  to  diarrhoea. 

The  so-called  whey  cure  is  a  means  of  treatment  sometimes  re- 
sorted to  in  cases  of  dyspepsia,  especially  when  occurring  in  gross 
feeders  (*  abdominal  plethora ').  Its  range  of  usefulness  is  much  the 
same  as  that  of  the  grape  cure,  and,  as  in  it,  large  allowance  must  be 
made  for  the  favourable  influence  of  the  open  air  and  exercise  which 
form  a  part  of  the  regimen.  The  quantity  of  whey  consumed  is  at 
first  limited  to  a  tumblerful  night  and  morning,  but  the  amount  is 
gradually  increased  until  a  maximum  is  reached  of  ten  tumblerfuls 
per  day.     The  only  other  foods  allowed  are  vegetables  and  fruits. 

1  Casein,  Ltd.,  Battersea,  S.W. 

*  See  Ashby,  Edin.  Med.  Journ.,  1899,  N.S.,  v.  389. 


CREAM  133 

It  should  be  added  that  whey  is  sometimes  a  useful  addition  to  the 
diet  in  cases  of  nephritis  accompanied  by  constipation  and  in  cases  of 
uric  acid  gravel.  It  may  also  be  substituted  for  milk  with  advantage 
when  jaundice  is  present,  and  in  cases  of  typhoid  fever  when  curds 
are  passed  in  the  stools. 

Cream. 

Cream  consists  essentially  of  the  fat  of  milk.  It  would  be  a 
mistake,  however,  to  suppose  that  it  consists  of  that  alone.  It 
contains  in  addition  protein  and  sugar  in  nearly  as  high  proportion  as 
milk  itself.^  The  main  diflference,  indeed,  between  milk  and  cream  is 
that  in  the  latter  some  of  the  water  of  the  milk  has  been  replaced  by  fat. 

The  exact  amount  of  fat  in  cream  varies  very  much,  the  differences 
depending  to  a  large  extent  on  the  method  by  which  the  cream  has 
been  separated.  In  cream  produced  by  a  centrifuge  the  proportion 
of  fat  may  amount  to  65  per  cent.,  while  in  ordinary  cream,  obtained 
by  skimming,  it  may  be  merely  20  per  cent,  or  less.  The  average 
amount  of  fat  in  specimens  of  centrifugal  cream  examined  by 
Droop  Richmond  in  1894  was  48"9  per  cent.  In  716  samples 
obtained  from  the  London  market  in  1889  Vieth  found  an  average 
of  45-J-  per  cent,  for  single  and  53^  for  double  cream.^ 

On  an  average,  perhaps,  one  may  say  that  a  sample  of  good  cream 
should  contain  41  per  cent,  of  fat.  There  is  thus  as  much,  or  even 
greater,  need  for  fixing  a  legal  standard  for  cream  as  there  is  for 
milk.  Some  authorities'  would  fix  the  standard  at  45  per  cent,  of 
fat ;  others  would  make  it  illegal  to  sell  as  cream  anything  which 
contains  less  than  25  per  cent.* 

The  well-known  Devonshire  or  clotted  cream  is  a  special  variety 
prepared  by  heating  the  milk  in  deep  pans,  which  causes  a  rapid  and 
very  complete  separation  of  the  fat.  The  proportion  of  fat  in  such 
cream  is  not  far  short  of  60  per  cent.,  as  is  shown  in  the  following 
analyses  :* 

Water.  Protein  *nd  p^  ^^ 

Sugar. 

1.  3248  ••  860  ••  58'2i  .,  0-71 

2.  35-54  ..  6-8o  ..  5709  ..  057 

Devonshire  cream  contains  only  about  half  as  much  sugar  as 
ordinary  cream.  For  this  reason  it  is  peculiarly  suited  to  be  a 
source  of  fat  in  the  dietary  of  diabetics. 

1  Cream  contains  about  2*5  per  cent,  of  protein,  4*5  per  cent,  of  sugar,  and 
0*5  per  cent,  of  mineral  matter. 

•  Milchziitung,  1889,  p.  142.  *  Pearmain  and  Moor. 

*  Wynter  Blyth.  •  Droop  Richmond,  Analyst,  1896,  p.  88. 


134  FOOD  AND  DIETETICS 

In  a  physiological  sense  cream  is  chiefly  to  be  regarded  as  a  fuel 
food.  It  has  been  calculated  that  a  pint  of  it  should  yield  about 
1,425  Calories,  or  about  as  much  as  i^  pounds  of  bread  or  i^  dozen 
bananas  or  4^  pounds  of  potatoes. 

In  sick-room  feeding  it  is  an  important  aid  in  getting  fat  into  the 
diet,  for  it  is  very  easily  digested.  Good  cream  (45  per  cent.) 
contains  as  much  fat  as  a  similar  quantity  of  most  cod-liver  oil 
emulsions,  and  is  usually  much  better  borne.  A  gill  of  it  per  day  is 
a  not  uncommon  prescription. 

Cream,  however,  is  by  no  means  an  economical  source  of  fat. 
One  and  a  half  pints  of  it  do  not  contain  more  fat  than  one  pound  of 
butter,  and  cost  about  three  times  as  much.  Cream,  therefore,  is  to 
be  regarded  as  a  luxury. 

Butter. 

Butter  is  produced  from  cream  by  churning.  This  causes  all  the 
fat  globules  in  the  cream  to  run  together  into  a  solid  mass,  while 
the  fluid  part,  containing  almost  all  the  sugar  and  most  of  the 
casein,  remains  in  the  form  of  butter-milk  The  flavour  and  aroma 
of  butter  are  due  to  the  growth  of  organisms  in  the  cream  during 
ripening ;  butter  prepared  from  pasteurized  cream  is  devoid  of 
flavour.^ 

The  trace  of  casein  which  remains  in  the  butter  is  of  importance,  for 
the  decomposition  which  it  undergoes  on  keeping  is  apt  to  make  the 
butter  turn  rancid.  The  presence  of  water  in  the  butter  facilitates 
this  change.  Butter  can  be  made  to  keep  indefinitely  by  melting  it 
down,  and  then  boiling  it  till  all  the  water  is  driven  off,  as  evidenced 
by  the  cessation  of  violent  ebullition.  The  melted  butter  is  then 
strained  through  muslin  to  remove  the  casein,  poured  into  a  bottle, 
and  allowed  to  cool.  If  corked  up,  it  will  keep  almost  indefinitely, 
and  when  wanted  a  portion  can  be  removed  with  a  cheese  scoop,  or 
the  butter  can  be  melted  and  poured  out  by  standing  the  bottle  in 
hot  water  for  a  short  time.  This  method  is  largely  used  in  India 
for  the  preservation  of  butter  (ghee),  and  also  on  the  Continent. 

The  exact  amount  of  fat  in  Ijutter  varies  within  fairly  wide  limits, 
but  averages  about  82  per  cent.,  or  twice  as  much  as  the  amount  in 
cream.  An  ounce  of  butter,  therefore,  may  be  reckoned  as  the 
equivalent  of  4  ounce  of  pure  fat.  In  addition  butter  contains  1 2  to 
15  per  cent,  of  water  and  about  2  per  cent,  of  non-fatty  organic 
matter,  chiefly  casein  and  milk-sugar. 

1  See  Ninth  Annual  Report  of  Storrs  Agricultural  Experiment  Station,  1896. 


BUTTER  AND  MARGARINE  135 

The  most  striking  chemical  characteristic  of  butter  fat  is  its  rich- 
ness in  those  fatty  acids  (butyric,  caproic,  capric,  and  caprylic) 
which  are  soluble  in  water.  Of  these  it  contains  about  7  per  cent. 
Butyric  acid,  indeed,  may  be  said  to  be  the  hall-mark  of  butter,  from 
which  it  derives  its  name.  Of  the  insoluble  fatty  acids  present  oleic 
is  the  most  abundant.  Butter  fat  contains  40  per  cent  of  olein. 
This  means  that  it  has  a  low  melting-point  (31-34°  C),  and  that  in  its 
turn  implies,  for  reasons  we  have  already  discussed,  that  it  is  easily 
digested  and  absorbed.  As  a  matter  of  fact,  butter  is  the  most  easily 
digested  of  fatty  foods.  The  fat  of  the  human  body  has  also  a  large 
proportion  of  olein,  and  melts  at  an  even  lower  temperature  than 
butter  (25°  C).  The  fact  that  butter  fat  approximates  so  closely  to 
it  in  its  proportion  of  olein  may  perhaps  help  to  explain  the  great  value 
of  butter  as  a  food. 

The  ease  with  which  butter  is  digested  renders  it  of  great  value 
as  a  source  of  fat  in  the  diet  of  sickness.  In  phthisis,  diabetes, 
and  many  forms  of  dyspepsia,  patients  can  take  ^  pound  of  it  a 
day  without  difficulty,  and  with  great  advantage  to  their  nutrition. 
Cooked  butter,  on  the  other  hand,  is  much  more  apt  to  disagree, 
probably  owing  to  the  liberation  of  fatty  acids  in  it  by  the  heat 
employed  in  cooking.  The  absorption  of  butter  in  the  intestine  is 
very  complete.  Even  w^hen  ^  pound  of  it  is  taken  per  day,  less 
than  '5  per  cent,  is  wasted.  This  is  a  more  favourable  result  than 
would  be  obtained  with  any  other  form  of  fat,  and  should  teach  us 
that  it  may  be  well  to  give  butter  a  fair  trial  before  having  recourse 
to  cod-liver  oil  or  other  medicinal  fatty  preparations. 

Margarine. 

From  what  has  been  said  as  to  the  chemical  composition  of  butter, 
■      vill   be   apparent    that   if  part   of   the   more   solid    constituents 

utarin  and  palmitin)  could  be  removed  from  ordinary  animal  fats, 
leaving  chiefly  olein,  the  substance  left  would  resemble  V:)utter  very 
closely.  As  a  matter  of  fact,  that  can  be  done,  and  the  product  is 
known  as  margarine.  ^ 

Margarine  owes  its  origin  to  the  ingenuity  of  the  French  chemist 
Mfeges-Mourifes,  and  was  first  manufactured  under  his  direction  for 
use  in  the  French  Navy  in  the  year  1870.  It  was  originally  made 
by  melting  down  and  clarifying  various  animal  fats,  that  of  the  ox 

1  Margarine  derives  its  name  from  '  margarin,'  a  supposed  fat,  really  a  mixture 
of  palmitin  and  stearin.  It  is  also  known  as  'oleomargarine,'  '  butterine,"  and 
'  Dutch  butter,'  but  by  the  Act  of  1887  all  butter  substitutes  are  now  described  as 
*  margarine. '     In  the  United  States  the  term  '  oleomargarine '  is  employed. 


136  FOOD  AND  DIETETICS 

being  chiefly  employed ;  but  at  the  present  day  vegetable  fats 
derived  from  nuts  and  various  seeds  are  largely  used  in  its  manu- 
facture. The  melted  fat  is  allowed  to  cool  slowly,  with  the  result 
that  the  stearin  solidifies  first.  The  more  fluid  components  (palmitin 
and  olein)  are  removed  by  pressure  and  churned  up  with  a  little 
milk  to  give  them  the  flavour  of  butter.  The  product  is  then  tinted 
with  some  vegetable  dye,  preserved  by  the  addition  of  a  little  boric 
acid,  and  is  ready  for  use.     It  has  the  following  composition  :* 

Water  ,.         .,         ,,         ..       9*3  per  cent. 

Protein  ,,         ,,         ,,         ..       1*3        „ 

Fat 827        .. 

Ash 67        „ 

It  will  be  observed  that  the  proportion  of  fat  is  exactly  the  same 
as  in  an  average  specimen  of  butter,  and  the  only  point  in  which 
the  two  differ  is  that  butter  has  a  much  higher  proportion  of  the 
soluble  and  volatile  fatty  acids. ^  There  is  no  reason  to  believe  that 
this  is  in  any  way  to  the  disadvantage  of  margarine  as  a  food.  The 
fat  of  our  bodies  contains  no  soluble  fatty  acids,  and  human  milk 
fat  is  almost  destitute  of  them  too.  Indeed,  one  might  almost  regard 
the  absence  of  butyrin  as  a  point  in  favour  of  margarine,  for  when 
butter  becomes  at  all  rancid  butyric  acid  is  liberated  from  the 
butyrin,  and  butyric  acid  is  an  exceedingly  irritating  substance. 
The  comparative  absence  of  casein  in  margarine  is  also  a  good  point, 
for  casein,  as  we  have  seen,  tends  to  promote  the  decomposition  of 
butter,  and  its  absence  should  help  margarine  to  keep  better. 

So  much  from  the  chemical  side.  From  a  physiological  point  of 
view  margarine  is  equally  deserving  of  recommendation.  It  is 
absorbed  almost  as  completely  as  butter,  the  difference  being  only 
about  2  per  cent.  In  other  words,  102  pounds  of  margarine  are 
equal  in  nutritive  value  to  100  pounds  of  butter.^  Whatever  may 
once  have  been  the  case,  margarine  is  now  made  only  from  pure 
fats,  and  the  processes  to  which  it  is  subjected  in  manufacture 
insure  its  further  purification.  As  the  flavour  of  the  best  variety  is 
equal  to  that  of  an  average  specimen  of  butter,  and  as  it  has  the 
advantage  of  being  very  much  cheaper,  there  is  every  reason  to  wish 
that  the  prejudice  against  it,  which  is  still  rather  widespread,  should 
quickly  disappear,  and  that  it  should  be  welcomed  as  an  admirable 
and  cheap  substitute  for  a  rather  expensive,  but  necessary,  food. 
It  has  been  objected  to  margarine  that  it  may  be  deficient  in 
*  vitamines,*  which  are  present  in  butter.     To  this  it  may  be  replied 

1  Average  of  thirty-five  analyses  by  Atwater. 

•  Butter  has  7^  per  cent,  of  butyrin  ;  margarine  has  only  0*25  per  cent. 

•  See  Rottger,  '  Lehrbuch  der  Nahrungsmittel  Chemie,'  p.  1S2. 


BUTTER  VERSUS  JAM  137 

that  there  is  no  proof  that  butter  contains  vitamines,  and  in  any 
case,  in  a  mixed  diet,  the  matter  is  one  of  no  importance.  The 
further  objection  that  fats  of  vegetable  origin  may  not  play  the  same 
part  in  metabolism  as  animal  fats  is  purely  speculative. 

Before  leaving  the  subject  of  butter,  one  may  consider  for  a 
moment  what  is  its  relative  value  as  an  addition  to  the  diet  when 
compared  with  jam.  This  subject  is  one  of  very  considerable  interest 
to  the  poorer  sections  of  the  community,  and  involves  really  two 
questions :  (i)  To  what  extent  can  sugar  (which  is  the  most 
important  ingredient  of  jam)  replace  fat  in  the  diet  ?  and,  (2)  Is  the 
replacement  effected  at  a  saving  of  expense  ? 

The  first  of  these  questions  has  been  dealt  with  to  some  extent  in 
a  previous  chapter  (p.  26).  It  need  only  be  repeated  here  that 
I  part  of  fat  is  equal  to  2^  parts  of  sugar  in  fuel  value,  and  that 
sugar  and  fat  can  replace  one  another  to  a  considerable  extent 
provided  these  proportions  be  observed.  It  would  seem,  however, 
although  one  cannot  give  any  definite  scientific  reason  why  it  should 
be  so,  that  fat  cannot  be  wholly  replaced  in  the  diet  by  sugar  or  other 
carbohydrate  without  detriment  to  health,  and  that  this  is  especially 
true  of  young  children. 

As  regards  the  second  question,  it  can  easily  be  shown  that,  even 
were  the  substitution  of  jam  for  butter  justifiable  on  physiological 
grounds,  it  cannot  be  eflfected  with  any  real  economy.  It  would 
require  about  3  pounds  of  jam  to  be  equal  in  fuel  value  to  i  pound 
of  butter,  and  at  current  prices  the  former  would  cost  about  is.  3d., 
the  latter,  say,  is.  2d.,  a  difference  slightly  in  favour  of  butter.^  In 
order,  therefore,  to  effect  any  saving  by  substituting  jam  for  butter, 
one  would  require  to  eat  less  of  the  former  than  would  really  replace 
the  butter,  the  result  of  which  would  be  that  one's  nutrition  would 
suffer.     The  money  saved  would  be  balanced  by  vigour  lost. 

The  subject  is  further  complicated  by  the  fact  that  it  takes  a 
greater  weight  of  jam  than  of  butter  to  cover  any  given  piece  of 
bread.  I  have  found  that  an  ordinary  slice  of  bread,  when  spread 
the  usual  thickness,  is  covered  by  40  grammes  (if  ounces)  of  jam  or 
by  S  grammes  (about  \  ounce)  of  butter.  In  other  words,  as  actually 
used,  it  takes  5  pounds  of  jam  to  go  as  far  as  i  pound  of  butter ;  and 
although  it  is  true  that  the  number  of  Calories  yielded  by  the  former 

*  This  calculation  is  based  on  the  assumption  (1)  that  i  part  of  fat  is  equal  in 
fuel  value  to  2^  parts  of  carbohydrate,  and  (2)  that  ordinary  jam  contains  about 
60  per  cent,  of  sugar  (see  a  paper  by  Aitchison  Robertson,  Scottish  Medical  and 
Surgical  Journ.,  1898,  iii.  31)  and  a  good  sample  of  butter  82  per  cent,  of  fat. 
Some  physiologists  (e.g.,  C.  Voit)  assume  a  different  ratio  between  fat  and 
carbohydrate,  namely,  that  100  parts  of  the  former  are  equivalent  to  175  of  the 
latter.  On  this  basis,  aj  pousds  of  jam  would  be  equal  in  value  to  i  pound  oi 
butter,  and  the  former  would  cost  i^.  less  than  the  latter. 


138  FOOD  AND  DIETETICS 

quantity  is  about  one-third  greater  than  that  obtained  from  the  latter, 
yet  the  cost  is  also  considerably  greater. 

Notwithstanding,  then,  that  the  cost  of  butter  and  jam  is,  from  a 
nutritive  point  of  view,  almost  equal,  the  housewife  will  always  find 
the  latter  more  costly  than  the  former,  simply  because  more  of  it  is 
used.  It  is  true  that  the  extra  quantity  of  jam  conveys  some  extra 
carbohydrate  into  the  body,  but  that  result  could  be  achieved  at  less 
cost  by  the  consumption  of  a  larger  amount  of  bread. 

At  the  same  time,  it  must  be  admitted  that  one  pays  dearly  for 
the  pleasant  flavour  of  butter.  As  far  as  nourishment  is  concerned, 
a  pound  of  dripping  is  more  than  the  equal  of  a  pound  of  butter, 
and  only  costs  half  as  much. 

We  have  here  another  example  of  the  fact,  already  so  often  pointed 
out,  that  in  buying  foods  we  pay  usually  for  the  likings  of  the  palate 
rather  than  for  the  needs  of  the  body.  For  those  who  can  afford  it, 
that  may  be  quite  justifiable,  but  for  the  poor  the  advantages  of 
margarine  and  dripping  as  cheap  sources  of  fat  cannot  be  too 
strongly  insisted  upon. 

Butter-milk. 

Butter-milk  is  the  fluid  which  is  left  after  the  fat  has  been  removed 

from  cream  by  churning.     Its  sourness  is  due  to  the  presence  of 

lactic  acid,  of  which,  however,  it  does  not  usually  contain  more  than 

J  to  ^  per  cent.      Its   general   composition  is  shown  in   the   two 

following  analyses : 

Protein.  Fat,  Carbohydrate. 

I.  3'o     ..         ••         ..     o'5     ..         ,,         ..     4'8' 
2-  237 04     ..         ..         ..     379» 

The  chief  point  in  which  it  differs  from  milk  is  its  poverty  in  fat. 
In  this  respect  it  resembles  skim  milk.  The  loss  of  milk-sugar  from 
the  formation  of  lactic  acid  is  too  small  to  be  of  any  significance. 

Butter-milk  is  very  easily  digested,  owing  to  the  absence  of  fat  and 
to  the  fact  that  its  casein  is  present  in  a  finely  flocculent  form.^ 

Its  nutritive  value  is  considerable,  an  ordinary  glassful  yielding 
about  as  much  nourishment  as  2  ounces  of  bread.  It  is  as  a  cheap 
source  of  protein,  however,  that  butter-milk  is  chiefly  deserving  of 
notice.  In  respect  of  this  constituent,  it  is  not  one  whit  inferior  to 
ordinary  milk,  and  yet  butter-milk  is  usually  thrown  out  to  the  pigs. 
There  can  be  no  question  that  there  is  here  a  great  waste  of  a  very 
valuable  food.  When  used  in  large  quantities,  butter-milk  has 
diuretic  properties  which  may  be  a  slight  disadvantage  in  health, 

*  Atwater.  ^  Dunlop,  'Report  on  Prison  Dietaries,'  p.  21,  1899. 

'  The  ease  with  which  butter-milk  can  be  digested  has  led  to  its  being  recom 
mended  as  a  food  for  infants  (see  a  paper  in  the  Brit.  Med.Journ.,  1902,  ii.  692). 


KOUMISS  AND  KEPHIR  139 

but  would  rather  enhance  its  value  than  otherwise  in  many  cases  of 
disease. 

Koumiss  and  Kephir. 

Komniss  is  a  milk  preparation  of  very  considerable  antiquity.  We 
find  authentic  accounts  of  it  in  books  written  early  in  the  thirteenth 
century,  and  hints  of  its  existence  almost  as  far  back  as  the  dawn  of 
Christianity  itself. 

Koumiss  is  fermented  mare's  milk.  Kephir  is  a  more  modern 
substitute  for  it  produced  from  the  milk  of  the  cow. 

The  home  of  koumiss  is  in  the  steppes  of  European  Russia  and  of 
Central  and  South-Westem  Asia.  Its  brewers  are  tribes  of  nomadic 
Tartars  ;  its  source  the  milk  of  the  hardy  mares  of  the  steppes. 

Kephir  is,  as  it  were,  a  spurious  koumiss,  and  was  first  produced 
in  the  Caucasus  Mountains  from  cow's  milk  fermented  with  kephir 
grains.^ 

It  may  be  regarded  as  bearing  much  the  same  relation  to  koumiss 
that  margarine  does  to  butter.  It  probably  has,  for  all  practical 
purposes,  the  same  nutritive  qualities  and  value  as  koumiss,  but  it 
is  not  the  genuine  article,  and  most  likely  it  would  never  be  used 
as  a  substitute  were  it  not  for  the  difficulty  of  obtaining  mare's 
milk  in  civilized  countries.  The  fermentation  which  milk  undergoes 
in  the  process  of  conversion  into  koumiss  or  kephir  is  a  double  one. 
The  sugar  of  the  milk  is  partly  converted  into  lactic  acid  by  the 
same  process  which  takes  place  when  milk  turns  sour  ;  in  part  also 
it  undergoes  the  same  changes  as  those  by  which  wine  is  produced 
from  the  sugar  contained  in  the  juice  of  the  grape.  A  '  lactic  '  and 
a  *  vinous  '  fermentation  both  go  on.  The  former  begins  first,  but 
the  latter  lasts  longest,  and  the  chief  anxiety  of  the  koumiss-maker 
is  to  promote  the  growth  of  the  vinous  ferment  and  to  restrain  that 
which  produces  lactic  acid. 

Now,  it  is  found  that  mare's  milk  is  a  better  medium  for  this 

double  fermentation  than  is  the  milk  of  the  cow,  and  it  is  so,  oddly 

enough,  for  those  very  reasons  which  make  it  a  poorer  food  than 

cow's  milk.     Mare's  milk  contains  less  casein  and  fat  than  cow's 

milk,  but  is  richer  than  the  latter  in  sugar.     Not  only  so:  the  sugar 

1  Kephir  grains  resemble  little  fragments  of  cauliflower.  Their  fermentative 
power  appears  to  be  entirely  due  to  the  Saccharomyces  mycoderma.  In  addition  to 
this,  they  contain  lactic-acid-producing  organisms.  The  so-called  Bacterium 
dispora  Caucasica,  which  they  also  contain,  does  not  appear  to  play  any  essential 
r61e  in  the  process,  unless,  perhaps,  it  helps  to  liquefy  the  precipitated  caseinogen 
{see  Nature,  1884  xxx.  216;  also  Rothschild,  '  L'AUaitement,'- Paris,  1898).  For 
a  full  account  of  the  history  of  kephir  and  the  mode  of  preparing  it,  see  '  Le 
Kephir,'  by  W.  Podwyssotsky  (Paris :  C.  Naud,  1902).  This  monograph  also 
contains  a  very  full  bibliography. 


i4«  FOOD  AND  DIETETICS 

of  mare's  milk  seems  to  lend  itself  more  readily  to  lactic  acid  fermen- 
tation than  the  sugar  of  cow's  milk  does.  The  richness  of  cow's  milk 
m  fat  is  a  positive  disadvantage  in  the  process  of  fermentation,  for 
there  is  apt  to  be  produced  from  it  small  quantities  of  butyric  acid, 
which  is  extremely  irritating  to  the  stomach,  and  renders  the  *  brew' 
unfit  for  consumption.  So  much  is  this  the  case,  that  even  if  the 
mares  are  allowed  to  pasture  on  rich  grass  for  but  one  day  the  milk 
of  that  day  becomes  unduly  rich  in  fat,  and  cannot  be  safely  used 
for  the  production  of  koumiss.^  Hence  it  is  that,  if  cow's  milk  is 
to  be  fermented — i.e.,  if  one  wishes  to  make  kephir — it  must  first 
be  made  to  approximate  in  composition  to  mare's  milk  by  being 
skimmed  or  diluted,  or  even  submitted  to  both  processes. 

The  chemical  changes  which  take  place  in  the  milk  under  the 
double  fermentation  are  not  difficult  to  follow.  The  lactic  ferment 
simply  changes  part  of  the  sugar  into  lactic  acid.  The  vinous 
ferment  eats  up  a  very  small  part  of  the  protein  of  the  milk,  and  at 
the  same  time  produces  from  the  sugar  a  little  alcohol  and  a  good 
deal  of  carbonic  acid  gas.  The  milk  thus  becomes  sour,  it  effer- 
vesces, and  is  weakly  alcoholic.  But  the  lactic  acid  causes  the 
casein  to  be  precipitated  just  as  it  does  in  the  ordinary  souring  of 
milk,  and  the  casein  falls  down  in  flocculi. 

Now,  one  of  the  essential  points  in  the  making  of  koumiss  is  that 
during  the  whole  process  of  fermentation  the  milk  should  be  kept 
constantly  agitated  by  stirring.  This  agitation  is  primarily  intended 
to  permit  of  the  access  of  oxygen  to  the  fermenting  fluid,  but  it  has 
also  the  result  of  breaking  up  the  precipitated  casein  into  exceedingly 
fine  particles,  and  it  is  to  this  extremely  fine  state  of  division  in 
which  the  casein  is  found  that  much  of  the  ease  with  which  koumiss 
can  be  digested  is  to  be  attributed.  As  the  process  goes  on,  it 
would  appear2  that  a  small  part,  at  least,  of  the  casein  undergoes  a 
sort  of  spontaneous  digestion,  and  is  converted  into  soluble  products.* 
One  certainly  finds  that  ordinary  kephir  contains  a  small  amount  of 
peptone. 

These  changes,  of  course,  only  go  on  gradually,  so  that  at  the  end 
of  twelve  hours  of  fermentation  one  gets  a  •  weak  '  koumiss  which  is 
only  slightly  sour,  and  which  still  looks  and  tastes  quite  milky. 
After  twenty-four  hours  have  elapsed  some  of  the  casein  has  been 
redissolved,  with  the  result  that  the  koumiss  is  thinner  ;  it  has  also 
increased  in  sourness.  This  is  called  '  medium '  koumiss.  After 
another  twenty-four  hours  or  more  most  of  the  sugar  has  been 

^  Carrick,  '  Koumiss,'  pp.  45,  54. 

*  Ibid.,  p.  41 ;  also  Food  and  Sanitation,  May  22,  1897. 

*  Acid  albumin,  albumose  and  peptone  {vide  Food  and  Sanitation,  May  27,  1897). 


KOUMISS  AND  KEPHIR 


141 


destroyed,  and  the  '  strong '  koumiss  which  results  is  a  thin,  sour 
fluid  which  effervesces  briskly.  In  this  form  it  can  be  kept  in- 
definitely without  undergoing  much  further  change. 

The  net  change  which  has  taken  place  in  the  original  milk  may  be 
summed  up  by  saying  that  the  sugar  has  been  to  a  large  extent 
replaced  by  lactic  acid,  alcohol,  and  carbonic  acid  gas ;  the  casein 
has  been  partly  precipitated  in  a  state  of  very  fine  division,  and 
partly  predigested  and  dissolved,  while  the  fat  and  salts  have  been 
left  much  as  they  were. 

That  this  is  an  accurate  summary  of  what  takes  place  is  borne  out 
by  the  following  analyses : 


Protein 
per  cent. 

Sugar 
per  cent. 

Fat 
per  cent. 

Salts 
per  cent. 

Alcohol 
per  cent. 

Lactic 

Acid 
per  cent. 

Koumiss* 

Kephir* 

Mare's  milk* 
Cow's  milk* 
Butter-milk» 

2*2 
31 

2-6 

3  3 

3-8 

I  "5 
1-6 

5*5 
4-8 

33 

2-1 

2'0 

2-5 
3-6 

1-2 

0-9 

0-8 

0-5 
07 
0-6 

17 
2*1 

o-g 
0-8 

0-3 

It  will  be  observed  from  the  table  that  the  total  protein  is  hardly 
less  in  koumiss  and  kephir  than  in  mare's  and  cow's  milk  respectively. 
In  koumiss  the  fat  is  practically  the  same  as  that  in  mare's  milk, 
while  the  percentage  of  fat  in  kephir  is  naturally  lower  than  that  in 
cow's  milk  owing  to  its  partial  removal  before  fermentation  is  begun. 
The  sugar  in  both  milks  is  very  considerably  reduced,  and  is  partly 
replaced  by  nearly  i  per  cent.,  or  sometimes  even  i^  per  cent.,  of 
lactic  acid. 

The  amount  of  alcohol  in  both  koumiss  and  kephir  is  less  than 
2  per  cent.  This  is  not  more  than  the  percentage  present  in  many 
so-called  temperance  beverages,  and  is  below  the  standard  fixed  by 
the  Excise.  As  a  matter  of  fact,  it  is  impossible  to  get  drunk  upon 
koumiss,  no  matter  how  much  of  it  is  consumed.^  At  most  only  a 
slight  degree  of  '  hilarity  '  is  produced,  followed  by  sleepiness,  bat  no 
headache. 

Looking  at  kephir  in  the  light  of  what  we  have  already  learnt 

as  to  the  digestibility  of  cow's  milk,  one  will  easily  perceive  that  the 

process  of   fermentation  must  render  the  latter  much  more  easily 

digested  and  absorbed  than  it  is  in  its  natural  state.     The  casein — 

'  Rubner,  'Leyden's  Handbuch,'  p.  93.  *  Ibid. 

»  Wynter  Blyth,  '  Foods,'  4th  edit.,  p.  258. 

<  Pearmain  and  Moor,  '  Milk  and  Milk  Products,'  p.  4. 

*  Rubner,  '  Leyden's  Handbuch,'  p.  94. 

•  Dahl,  quoted  by  Carrick,  loc.  cit.,  p.  113. 


142  FOOD  AND  DIETETICS 

the  great  obstacle  to  the  easy  digestion  of  cow's  milk — is  in  such 
a  form  that  it  cannot  form  masses  in  the  stomach,  but  is  readily 
attacked  by  the  digestive  juices ;  indeed,  it  is  already  partly  digested. 
The  carbonic  acid  stimulates  the  stomach  to  a  more  abundant  secre- 
tion of  gastric  juice  and  promotes  the  absorption  of  the  fat  (see 
p.  124).  The  alcohol  present  co-operates  in  aiding  the  process  of 
digestion  by  causing  the  blood  to  flow  more  briskly  through  the 
stomach  and  intestine,  and  in  addition  serves  as  a  food  itself.  The 
lactic  acid  reinforces  the  digestive  action  of  the  acid  of  the  stomach, 
and  may,  perhaps,  in  itself  contribute  heat  and  energy  to  the  body.i 
In  the  matter  of  absorption  koumiss  and  kephir  also  compare 
favourably  with  ordinary  milk.  May^  administered  to  a  patient 
6,432  grammes  of  kephir  in  two  days,  containing  724  grammes  of 
solid  matter.  He  found  that  the  percentages  of  loss  in  the  stools 
were  as  follows : 

Dry  substance  6*4  per  cent 

Nitrogen         ..         .•         .•         ..       0*4        ., 

Fat 39 

Ash 34-9 

The  absorption  here  was  evidently  better  than  that  of  milk, 
especially  as  far  as  nitrogen  and  fat  are  concerned. 

In  the  light  of  these  facts  one  has  no  difficulty  in  understanding 
how  it  is  that  enormous  quantities  of  koumiss  or  kephir  can  be 
disposed  of  in  the  body  without  any  difficulty.  We  read,  for 
instance,  that  the  healthy  dweller  on  the  steppes  is  capable  of  con- 
suming 3  or  4  gallons  of  koumiss  on  a  hot  summer's  day,  while  even 
the  debilitated  stomach  of  the  consumptive  is  equal  to  disposing  of 
ten  large  champagne  bottlefuls  in  the  twenty-four  hours.^ 

To  the  enormous  quantity  of  nutriment  thus  obtained,  rather  than 
to  any  mysterious  properties,  the  undoubtedly  high  curative  value 
of  koumiss  in  consumption  and  other  wasting  diseases  is  to  be 
attributed.  Postnikoff  sums  up  its  nutritive  qualities  in  the  three 
words,  '  nutrit,  roborat,  alterat.'*  It  has  also  the  advantage  of 
possessing  diuretic  properties  and  of  restraining  intestinal  putre- 
faction. 

It  has  been  calculated  that  4  litres  (3^  quarts)  of  an  average  brand 
of  koumiss  will  contain  the  following  amount  of  nutritive  material : 

»  For  experimental  proof  of  the  greater  digestibility  of  koumiss  than  cow's 
milk,  see  a  paper  on  Kefir  by  Dr.  Hallion  {Journ.  dcs  Practiciens,  p.  402,  June  27, 
1902). 

3  Maly's  Jahres-Bericht  Thier-Chemie,  1895,  ^^'^-  454- 

»  Carrick,  loc.  cit.  See  also  Dr.  Stange  on  Koumiss  Cures  (Ziemssen's  '  Hand- 
book of  General  Therapeutics,"  appendix  to  volume  on  '  Dietary  of  the  Sick '). 

*  Food  and  Sanitation,  May  27,  1897. 


KOUMISS  AND  KEPHIR  143 

Protein 140  grammes  =     600  Calories 

Fat  80        „         =     744        „ 

Carbohydrate     ..         .•         ..     140        „         =     574        „ 

1,918        „ 

This  is  two-thirds  of  the  total  amount  of  Calories  required  by  a  man 
doing  moderate  work,  and  contains  more  than  the  entire  amount  of 
protein  he  needs  daily,  and  yet  3J  quarts  of  koumiss  can  be  taken 
without  any  difficulty.^ 

A  glance  at  the  table  shows  also  that  kephir  is  almost  identical  in 
composition  with  genuine  koumiss ;  indeed,  being  prepared  from 
cow's  milk,  it  is  richer  in  casein,  and  must  therefore  be  regarded  as 
rather  the  better  preparation  of  the  two,  unless  for  those  of  very 
feeble  digestive  powers.  Good  kephir  is  now  prepared  by  most  of 
the  large  dairy  companies,  but  it  is  still  rather  expensive,  a  large 
champagne  bottleful  costing  about  a  shilling.  In  physiological 
properties  it  seems  to  be  identical  with  the  article  prepared  from 
mare's  milk.  The  koumiss  cure  is  thus  brought  to  one's  own  door, 
and  no  longer  necessitates  a  journey  to  the  steppes. 

In  addition  to  its  use  in  cases  of  phthisis,  koumiss  is  of  value  in 
all  conditions  of  impaired  nutrition,  in  continued  fevers,  and  in  con- 
valescence. It  may  also  be  used  with  advantage  in  chronic  catarrh 
of  the  stomach  or  bowels,  in  cases  of  hepatic  cirrhosis,  and  in  renal 
disease.  It  is  often  better  borne  in  vomiting  than  any  other  form  of 
food,  and  has  been  recommended  in  delirium  tremens.^  It  should 
be  given  in  small  quantities  at  first  (not  more  than  a  pint  in  the  day) 
and  in  small  doses,  and  gradually  increased  up  to  the  limit  of  the 
amount  which  can  be  taken  without  discomfort.  Koumiss  is  an 
acquired  taste ;  and  though  many  patients  object  to  it  at  first,  they 
usually  come  to  like  it  before  long. 

Soured  Milk,  which  somewhat  resembles  koumiss  in  its  properties, 
is  dealt  with  elsewhere  (p.  557). 

Casein  Preparations. 

In  practical  dietetics,  the  want  of  a  tasteless,  compact,  easily 
digested  and  moderately  cheap  preparation  of  pure  protein  is  often 
felt.  Casein  is  admirably  adapted  to  meet  these  requirements,  and 
has  now  been  separated  from  milk  and  introduced  as  a  dietetic  prep 

*  In  the  very  dry  atmosphere  of  the  steppes  these  enormous  quantities  of 
koumiss  can  be  taken,  but  in  the  damper  climate  of  England  only  a  more  moderate 
amount  can  be  compassed, 

»  See  'Cow's  Milk  Koumiss  as  a  Nutrient  in  Disease,'  by  Dr.  Brush  {Thcr»p. 
Gaxitte,  1903,  xxvii.  443). 


144  FOOD  AND  DIETETICS 

aration  on  its  own  account.  The  preparations  known  as  Plasmon, 
Protene,  Casumen,  Biogene,  etc.,  are  examples  of  pure  casein  pre- 
pared in  various  ways.    They  contain  about  80  per  cent,  of  protein. 

In  these  forms  casein  is  digested  with  ease  and  absorbed  almost 
in  its  entirety,  and  is  capable,  if  necessary,  of  replacing  all  other 
forms  of  protein  in  the  diet.^  Added  to  this,  casein  presents  some 
special  advantages  not  possessed  by  other  varieties  of  protein.  For 
one  thing,  it  is  readily  capable  of  *  fixing  *  acids,  and  so  neutralizing 
them.  The  power  of  casein  in  this  respect  is  three  times  greater 
than  that  of  an  equal  weight  of  beef.^  This  property  gives  it 
special  advantages  in  those  cases  of  dyspepsia  in  which  too  much 
acid  is  being  poured  into  the  stomach. 

Another  valuable  peculiarity  of  casein  is  that  it  contains  phos- 
phorus, which  is  found  also  in  the  products  of  its  digestion,  and  so 
enters  the  blood  in  an  organic  form,'  rendering  casein  a  valuable 
source  of  that  essential  constituent  of  all  our  tissues.  Further,  casein 
contains  in  itself  all  the  chemical  units  which  are  required  for  the 
building  up  of  the  various  body  proteins,  and  can  thus  cause  normal 
growth  even  if  it  is  the  sole  protein  present  in  the  diet. 

We  have  also  seen  that  casein  is  incapable  of  yielding  uric  acid  by 
its  decomposition,  and  its  use  is  thus  quite  admissible  in  cases  of 
gout. 

Lastly,  casein  is  so  easily  and  rapidly  absorbed  that  it  has  but 
little  opportunity  of  undergoing  putrefaction  in  the  intestine,  even 
if  it  does  not  itself,  as  some  have  supposed,  act  as  an  intestinal 
antiseptic* 

In  these  forms  casein  is  not  clotted  by  rennet,  but  it  is  thrown 
down  from  its  solution  by  the  addition  of  acids  in  rather  coarse 
flakes.  It  is  better,  therefore,  to  administer  it  mixed  with  other 
semi-solid  foods,  e.g.,  gruels  or  thick  soup,  rather  than  by  itself. 

The  nutritive  value  of  these  preparations  is  undoubtedly  very  high, 
containing  as  they  do  fully  80  per  cent,  of  pure  protein.  An  invalid 
does  not  require  more  than  80  grammes  of  protein  daily,  and  this 
quantity  would  be  covered  by  100  grammes  (3^  ounces)  of  Plasmon 
or  Casumen.  That  an  amount  almost  equal  to  this  can  be  adminis- 
tered daily  for  prolonged  periods  has  been  fully  proved  by  clinical 
experiment.^ 

'  Rohmann,  Berlin.  Klin.  Woch.^  1895,  xxxii.  519. 

'  Brandenburg,  Deut.  Archiv  f.  Klin.  Med.,  1896,  Iviii.  71. 

»  Salkowski,  Berlin.  Klin.  Woch.,  1894,  xxxi.  1063,  and  Deut.  Med.  Woch..  1896, 
xxii.  225. 

*  See  Salkowski,  loc.  cit.;  Schmitz,  Zeit.  f.  Physiolog.  Chemie,  1894,  xix.  378; 
and  Laquer,  Verhandl.  d.  Cong.  /.  Inn.  Med.,  1898,  xvi.  546. 

'  See  Oppler,  Therap.  Monatshe/ie,  1897,  xi.  201. 


CASEIN  PREPARATIONS  145 

It  is  as  a  means  of  enriching  the  diet  in  protein,  rather  than  as 
sources  of  energy,  that  these  preparations  are  specially  valuable. 
Roughly  speaking,  one  may  say  that  one  part  of  them  is  equal  as 
a  source  of  protein  to  four  parts  of  meat.  Their  tastelessness  and 
solubility  enables  them  to  be  added  to  other  foods,  such  as  soups, 
milk  puddings,  cocoa  and  jellies,  raising  greatly  their  nutritive 
value,  and  without  the  patient  being  aware  that  any  such  addition 
has  been  made.  In  many  cases  of  illness,  and  especially,  perhaps, 
in  fevers  and  diabetes,  they  increase  very  considerably  our  dietetic 
resources,  and  have  already  taken  an  important  place  in  treatment. 

They  are  far  superior  to  any  meat  preparation  as  condensed  forms 
of  protein. 

Sanatogen^  consists  of  casein  combined  with  5  per  cent,  of  glycero- 
phosphate of  sodium.  In  virtue  of  its  casein  it  has  the  same 
nutritive  value  as  the  other  preparations  considered  above.  The 
organic  phosphorus  which  it  contains  appears  to  be  fully  assimilated,^ 
and  is  believed  to  exert  a  tonic  effect  upon  the  nervous  system. 
Such  an  influence  is  conceivable,^  but  is  very  difficult  of  proof, 
and  the  claims  of  sanatogen  in  this  respect  rest  upon  a  purely 
empirical  basis,  although  it  is  only  fair  to  add  that  numerous  clinical 
observers  have  testified  to  the  benefits  derived  from  its  use. 

*  Sanaphos,  Branovim,  Vitafer,  and  Vi-Casein  are  substitutes  for  Sanatogen 
made  by  British  manufacturers. 

2  Tunnicli£fe,  '  Concerning  tlie  Behaviour  in  the  Body  of  Certain  Organic  and 
Inorganic  Phosphorus  Compounds '  {A  rchives  Internationales  de  Pharmacodynamie 
et  de  Therapie,  1906,  xvi.,  fascicule  i  and  2). 

*  For  a  discussion  of  the  role  of  the  phosphates  in  nutrition,  see  p.  296. 


10 


[h6] 


CHAPTER  IX 
CHEESE,  EGGS,  AND  EOQ  SUBSTITUTES 

Cheese. 

1.  Chemical  Composition. 

Cheese   consists  essentially  of  the  casein  and  fat  of  milk.     It  is 
prepared  in  two  ways  : 

1.  The  milk  may  be  allowed  to  clot  under  the  influence  of  rennet. 
If  pure  milk  be  so  treated,  the  resulting  cheese  will  contain  most  of 
the  fat — e.g.,  Cheddar — and  the  proportion  of  fat  may  be  rendered 
still  greater  by  adding  cream  to  the  milk — e.g.,  some  forms  of  Stilton. 
In  other  cases  part  of  the  cream  is  first  removed  by  skimming.  The 
cheese  will  then  be  proportionately  poor  in  fat — e.g.,  some  Dutch 
cheeses. 

2.  The  casein  may  be  precipitated  by  allowing  the  milk  to  become 
sour,  or  by  adding  to  it  an  acid,  such  as  vinegar.  Under  these  cir- 
cumstances the  casein  carries  down  with  it  but  little  fat,  and  the 
cheese  produced  is  a  '  lean '  cheese — e.g.,  some  Dutch  and  German 
cheeses. 

The  nature  of  the  cheese  will  also  depend  on  the  kind  of  milk 
from  which  it  is  derived.  In  by  far  the  majority  of  cases  cow's  milk 
is  the  source,  but  Parmesan  is  made  from  partly  skimmed  goat's 
milk,  and  Roquefort  from  the  milk  of  the  ewe.  In  whatever  way 
the  casein  is  obtained,  it  is  next  squeezed  to  remove  the  whey  which 
is  contained  in  it.  If  high  pressure  be  employed,  the  resulting 
cheese  is  '  hard,'  while  a  lower  degree  of  pressure  produces  a  '  soft ' 
cheese. 

The  chief  examples  of  hard  cheese  are  these  :  Parmesan,  Gouda, 
Edam,  Chester,  Cheddar,  Roquefort. 


MANUFACTURE  OF  CHEESE  147 

Amongst  the  soft  cheeses  are  the  following  :  Brie,  Camembert, 
Neufchatel,  Gorgonzola,  Limburg,  Stilton,  and  Cream. 

The  soft  cheeses  do  not  keep  well,  and  are  intended  for  immediate 
consumption. 

After  being  submitted  to  pressure,  the  next  step  is  to  set  the  mass 
of  casein  and  fat  aside  in  a  cool  place  to  '  ripen.'  This  process  is 
brought  about  by  the  agency  of  bacteria,  and  results  in  chemical 
changes  in  the  casein  which  are  not  as  yet  perfectly  understood. 
'  Amido  bodies,'  however,  seem  always  to  be  produced,  and  a  small 
amount  of  peptone.  Whether  or  not  the  fat  in  the  cheese  increases 
at  the  expense  of  the  casein  is  still  disputed. 

The  flavour  of  the  cheese  undoubtedly  depends  on  the  particular 
species  of  germ  which  has  found  access  to  it  during  the  ripening, 
each  species  producing  definite  chemical  bodies,  which  gfive  to  that 
particular  kind  of  cheese  its  peculiar  characteristics.  The  process 
seems  to  be  analogous  to  that  which  takes  place  in  the  manufacture 
of  wines.  By  the  use  of  different  yeasts,  one  can  produce  from  the 
same  grape-juice  wines  of  entirely  different  character  and  bouquet. 
So  with  cheese.  By  the  use  of  different  bacteria  one  should  be  able 
to  produce  from  the  same  casein  cheeses  of  quite  dissimilar  flavour. 
No  doubt  that  is  what  will  happen  in  the  future.  At  present  cheese- 
making  is  a  rule-of-thumb  process.  By-and-by  it  will  become  a 
science.  It  has  already  begun  to  be  so,  indeed,  in  Germany  and 
other  countries,  and  even  in  some  parts  of  England.  The  cheese- 
maker  of  the  future  will  have  a  laboratory  attached  to  his  factory, 
in  which  pure  cultures  of  the  bacteria  responsible  for  the  flavour  of 
each  variety  of  cheese  will  be  nursed,  and  instead  of  *  Stilton  '  coming 
from  one  district,  '  Gorgonzola  '  from  another,  and  '  Gruyfere  '  from  a 
third,  all  will  be  produced  under  one  roof.  We  may  look  forward 
then,  perhaps,  to  tasting  cheeses  hitherto  unknown,  and  to  combina- 
tions of  flavour  as  yet  unsuspected.  We  may  combine  the  virtues 
of  Stilton  with  Gorgonzola,  or  those  of  Gruyfere  with  Roquefort,  for 
the  artist  of  the  palate  will  have  in  his  hands  the  precise  instruments 
of  science. 

Whether  this  forecast  be  ever  verified  or  not,  there  is  little  doubt 
that  the  gross  chemistry  of  cheese  will  never  be  much  altered.  It 
must  always  remain,  for  all  practical  purposes,  a  compound  consist- 
ing essentially  of  protein  and  fat.  In  the  accompanying  table  there 
is  shown  the  average  composition  of  some  of  the  leading  cheeses 
met  with  in  the  market : 


148 


FOOD  AND  DIETETICS 


COMPOSITION 

OF  CHEESES.! 

Nitro- 

Average 

Real  Cost 

Cheese. 

Water. 

genous 
Matter. 

Fat. 

Ash. 

Cost 
per  lb. 

of  I  lb.  of 
Nutriment. 

American 

26-9 

32-9 

31 

4"5 

6d. 

8id. 

Brie* 

497 

18-9 

26-8 

4-5 

Camembert 

48-6 

21 'O 

217 

4'4 

II  oz.,  6d. 

8id. 

Cheddar   .. 

31  "9 

33-4 

26-8 

3  9 

9id. 

IS.  2d. 

Cheshire  . . 

332 

29-4 

307 

4-3 

9id. 

IS.   2d. 

Cream  (Fuin 

32  0 

28-6 

35  9 

15 

Dutch 

32-9 

30-8 

17-8 

6-3 

yd. 

lofd. 

Gloucester 

319 

367 

247 

4*4 

9id. 

IS.  2d. 

Gorgonzola          . . 

39'2 

25'9 

269 

47 

9d. 

IS.  3d. 

Gruyere    . . 

34'l 

31  "5 

28-2 

4-0 

lod. 

IS.  3d. 

Neufchatel 

4l'o 

143 

432 

14 

Parmesan 

30'0 

43-8 

i6-5 

5  9 

ii^d. 

IS.  4?d. 

Roquefort 

251 

34S 

31  5 

5-5 

IS.  i^d. 

IS.  6d. 

Stilton 

2y6 

23  "9 

38-9 

31 

IS.  2d. 

IS.  7d. 

St.  Ivel     . . 

35*9 

23  6 

35 -o 

37 

— 

— 

Taking  the  results  as  a  whole,  one  will  not  be  far  wrong  in 
regarding  cheese  as  made  up  of  one-third  of  water,  one-third  of 
nitrogenous  matter,  and  one-third  of  fat.  It  is  well  to  remember, 
however,  that  there  is  no  inconsiderable  amount  of  mineral  matter 
present  as  well,  consisting  chiefly  of  salts  of  lime,  and  that  some 
cheeses  at  least  may  contain  as  much  as  2  per  cent  of  milk-sugar. 

The  *  nitrogenous  matter '  consists  mainly,  but  by  no  means 
entirely,  of  proteins.  Stutzer  has  estimated  the  different  forms  in 
which  nitrogen  occurs  in  Camembert,  with  the  following  results:^ 


Total  N 
N  as  ammonia 
,,     amides 


=  2-9  % 
=  0-386  % 

=  i"ii7  % 


N  as  albumoses  and  peptones  =  0-885  % 
,,  casein  and  albumin  . .  =0*397  % 
,,     indigestible  forms    ..      =0*115% 


The  exact  proportions  of  these  different  nitrogenous  bodies  will 
naturally  vary  considerably  in  different  cheeses,  but  it  is  well  to 
note  the  large  amount  of  non-protein  nitrogen  present,  which  must 
be  allowed  for  in  an  estimate  of  the  nutritive  value  of  cheese. 


2.  Digestibility. 

The  infiltration  of  cheese  with  the  fat  which  it  contains  must 
always  render  it  an  article  of  diet  not  easily  dealt  with  by  delicate 
stomachs,  for  the  fat  forms  a  waterproof  coating,  which  prevents 
the  access  of  the  digestive  juices  to  the  casein. 

The  larger  the  lumps  of  cheese  which  reach  the  stomach,  the 
slower  will  this  access  be.     Hence  the  importance  of  reducing  the 

*  These  figures  are  constructed  by  taking  the  averages  of  the  analyses  collected 
by  Pearmain  and  Moor.     Prices  are  those  of  the  Stores. 

•  Konig.  3  Zeit.  f.  Analyt.  Chem.,  1896,  xxxv.,  p.  493. 


DIGESTIBILITY  OF  CHEESE  149 

cheese  to  a  state  of  fine  division  before  it  is  swallowed.  This  may 
be  done  by  careful  chewing.  Now,  it  is  more  easy  to  pulverize  a 
hard  morsel  than  a  soft  one,  for  the  latter  tends  always  to  elude  the 
teeth.  For  this  reason,  a  piece  of  hard,  dry  cheese  is  more  easily 
digested  than  a  soft  and  moist  piece.  A  better  plan,  however,  is 
to  break  up  the  cheese  before  it  is  eaten.  This  may  be  done  by 
grating,  but  a  better  way  is  to  dissolve  the  cheese,  and  then  mix  it 
through  some  other  form  of  food.  An  able  writer^  on  the  chemistry 
of  cookery  has  pointed  out  that  this  may  best  be  done  by  means  of 
bicarbonate  of  potash.  It  was  pointed  out,  when  speaking  of  the 
chemistry  of  casein,  that  it  forms  soluble  compounds  with  alkalies. 
Bicarbonate  of  potash  is  an  alkali,  and  it  seems  to  combine  with  the 
casein  of  the  cheese,  and  brings  the  latter  into  a  soluble  state.  As 
much  bicarbonate  of  potash  as  will  lie  on  a  threepenny  piece  is 
sufficient  to  dissolve  a  quarter  of  a  pound  of  cheese  if  the  latter  be 
first  grated  or  chopped  up  into  fragments.  By  the  addition  of  milk 
and  eggs,  a  very  savoury  a-nd  exceedingly  nutritious  pudding  or 
fondu  can  be  prepared,  and  at  a  very  small  cost.  It  is  certainly 
much  to  be  wished  that  we  should  avail  ourselves  more  frequently 
of  such  a  method  of  cooking  cheese  in  this  country.  If  cheese  is 
ever  to  take  the  place  that  it  ought  to  have  as  a  cheap  and 
convenient  form  of  protein  food,  some  such  method  must  be 
employed,  for  it  is  the  difficulty  with  which  cheese  is  digested  that 
renders  it  an  impossible  food  to  many  persons.' 

Another  reason,  probably,  for  the  disagreeable  effects  which  cheese 
is  apt  to  produce  in  the  stomach  is  that  in  the  process  of  ripening 
small  quantities  of  fatty  acids  are  produced,  and  these  are  always 
very  irritating.  The  addition  of  an  alkali  in  the  solution  of  the 
cheese  will  neutralize  these,  and  render  them  less  harmful. 

It  is  only  in  the  stomach  that  the  difficulty  of  digesting  cheese  occurs ; 
once  in  the  intestine,  it  is  absorbed  very  thoroughly,  over  90  per 
cent,  of  the  protein  being  retained  in  the  body,  and  nearly  90  per 
cent,  of  the  energy  it  contains  being  'available.'* 

3.   Nutritive  Value. 
Of  the  high  nutritive  value  of  cheese  there  can  be  no  doubt.     It 
is  just  what  would  be  expected  when  one  remembers  that  a  pound 
of,  say,  Cheddar  cheese  represents  the  total  casein  and  most  of  the 
fat  in  a  gallon  of  milk. 

1  Mattieu  Williams.  Others,  however,  have  not  found  that  the  bicarbonate 
has  any  appreciable  solvent  effect. 

2  See  also  'The  Claims  of  Cheese  as  a  Substitute  for  Meat,'  by  Francis  T. 
Bond,  M.D.  (The  Sanitary  and  Economic  Association,  Ltd.,  21,  George  Street, 
Gloucester).  »  U.S.Dept.  of  Agriculture,  Farmers'  Bulletin,  No.  487. 


150  FOOD  AND  DIETETICS 

The  average  amount  of  moisture  which  cheese  contains  is  33  per 
cent.,  the  remainder  being  made  up  of  protein  and  fat  in  varying,  but 
on  the  whole  fairly  equal,  proportions.  The  amount  of  water  in 
moderately  lean  beef  is  about  73  per  cent.,  the  remainder  being  also 
made  up  of  protein  and  fat,  the  former  always  largely  predominating. 

Beef,  then,  contains  less  than  half  as  much  nourishment  as  the 
same  weight  of  cheese.  Williams  goes  further  than  this,  and  asserts 
that  a  cheese  of  20  pounds  contains  as  much  nutriment  as  a  sheep's 
carcase  of  60  pounds. 

An  appeal  to  the  standard  of  the  Calorie  gives  the  same  verdict.  A 
pound  of  cheese  yields  fully  2,000  Calories  of  energy,  which  is  more 
than  three  times  the  amount  yielded  by  a  pound  of  moderately  lean 
beef.  Furthermore,  a  pound  of  cheese  can  be  obtained  at  about  one- 
sixth  of  the  cost  of  3  pounds  of  beef,  which  is  its  nutritive  equivalent, 
and  therefore  it  is  at  once  evident  that  cheese  is  a  substitute  for 
meat  which  should  be  of  the  greatest  value  in  poor  households. 

But  if  cheese  is  thus  to  become  a  cheap  substitute  for  meat,  it  is 
of  the  greatest  importance  what  variety  of  cheese  is  bought.  For  it 
is  true  of  cheese  in  an  even  greater  degree  than  of  most  other  foods, 
that  in  buying  it  we  pay  for  flavour,  not  for  food  value.  The  above 
table  shows  the  real  cost  of  one  pound  of  nutriment  as  obtained 
in  the  standard  brands  of  cheese.  By  the  real  cost  is  meant  what 
one  pound  of  the  protein  and  fat  contained  in  the  cheese  would 
actually  cost  if  all  the  water  were  excluded. 

The  table  brings  out  some  interesting  points.  It  shows,  for 
example,  that  American  (Canadian)  cheese  contains  rather  more 
nutriment  than  the  same  quantity  of  Parmesan,  and  at  one-half  the 
price.  Stilton,  again,  costs  twice  as  much  as  American,  and  contains 
about  the  same  proportion  of  real  food.  To  those  who  eat  cheese 
simply  for  the  sake  of  its  flavour,  and  append  it  as  a  savoury  to  the 
end  of  an  ample  meal,  these  considerations  are,  of  course,  of  no 
interest.  But  to  the  man  who  wishes  to  use  cheese  as  a  cheap  and 
efficient  substitute  for  meat  one  would  say,  Buy  Canadian  or  Dutch, 
and  preferably  the  former ;  for  in  that  way  you  will  be  getting  much 
the  most  nutriment — in  other  words,  much  the  most  muscle  and 
blood  and  brain — for  the  money  you  spend. 

Eggs. 

An  egg  is  an  undeveloped  chick.     This  may  sound  a  truism,  but 

it  is  the  key  to  the  right  understanding  of  the  value  of  eggs  as  food. 

For  if  the  chick  is  developed  from  the  egg  without  the  aid  of  any 

external  agency  save  heat,  it  follows  that  the  egg  must  contain 


EGGS  151 

within  itself  all  the  building  material  necessary  for  the  making  of  the 

chick,  along  with  such  a  supply  of  nutriment  as  the  latter  requires 

until  it  is  ready  to  be  hatched.     It  may  be  said  of  eggs,  indeed,  in 

the  words  of  Kingsley,  that  they  are  veritably 

•  Treasure-houses,  wherein  lie. 
Locked  by  angels'  alchemy, 
Milk  and  hair  and  blood  and  bone.' 

In  chemical  language  they  must  contain  much  protein  and  mineral 
matter  (especially  salts  of  lime,  phosphoric  acid,  and  iron),  for  these 
are  the  only  materials  out  of  which  '  blood  and  bone '  can  be  built 
up.  They  are  Ukely,  also,  to  contain  fat,  for  that  is  the  most 
compact  form  in  which  nutriment  for  the  young  chick  can  be  stored. 
And,  as  a  matter  of  fact,  it  is  practically  of  these  constituents  that 
an  egg  consists.  Carbohydrate  it  need  not  contain,  for  the  chief  use 
of  carbohydrate  is,  as  we  have  seen,  to  serve  as  a  source  of  muscular 
energy  ;  and  in  the  narrow  confines  of  an  eggshell  muscular  move- 
ment is  impossible. 

Passing  on  to  details,  it  may  be  said  that  a  hen's  egg  of  average 
size  weighs  about  50  grammes  (nearly  2  ounces),  the  weight  being 
distributed  as  follows : 

Shell i2percent.,or    6  grammes 

White 58  „  29 

Yolk 30  „  15 

The  shell  consists  almost  entirely  of  carbonate  of  lime.  As  the 
process  of  hatching  goes  on  it  becomes  much  thinner  by  absorption, 
and  one  might  think  that  it  was  used  as  a  storehouse  of  lime  which  is 
drawn  upon  for  the  formation  of  the  bones.  But  apparently  this  is  not 
so.    The  egg  seems  to  contain  in  itself  enough  lime  for  the  purpose.^ 

The  white  consists  of  a  solution  of  protein  shut  up  in  the  interior 
of  millions  of  cells.  When  white  of  egg  is  beaten  up,  the  walls  of 
the  cells  are  ruptured,  and  the  protein  escapes.  The  digestibility  of 
the  egg-white  is  thereby  increased,  for  the  walls  of  the  cells  offer  a 
slight  barrier  to  the  digestion  of  the  protein  which  they  contain. 

The  protein  of  white  of  egg  is  called  '  egg  albumin.'  It  would  be 
an  error,  however,  to  regard  it  as  a  single  substance.  It  seems  to 
consist  of  a  mixture  of  diflferent  proteins,  some  of  which  are  of  a 
compound  nature,  and  contain  a  carbohydrate  group  in  their  mole- 
cule.* This  has  some  bearings  on  the  use  of  eggs  as  a  food  for 
diabetics,  which  will  be  pointed  out  later. 

^  See  Voit  in  '  Hermann's  Handbuch,'  Bd.  vi.,  p.  459,  footnote. 

'  There  are  apparently  four  dififerent  proteins  in  egg-white — ovalbumin,  con- 
albumin,  ovomucin,  and  ovomucoid.  The  ovalbumin  makes  up  the  greater  part 
of  the  white.  Ovomucin  and  ovomucoid  are  glyco-proteins,  and  are  only  present 
in  small  amounts.  See  Eichholz,  Journ.  0/  Physiol.,  1898,  xxiii.  163,  and 
Farmers'  Bulletin,  No.  128,  United  States  Department  of  Agriculture. 


152  FOOD  AND  DIETETICS 

The  yolk  is  the  storehouse  of  nutriment  for  the  young  chick,  and 
consequently  has  a  very  different  composition  from  the  white.  It 
contains  much  less  water  and  more  solid  matters,  amongst  the  latter 
being  a  large  proportion  of  fat.  The  general  composition  of  the 
white  and  yolk  is  contrasted  in  the  following  table  (Konig),^and 
graphically  illustrated  in  the  accompanying  diagrams  (Figs.  9,  10) : 


Fig.  9. — Percentage  Composition  of 
THE  White  and  Yolk  of  an  Egg. 

Other  Non-  „. 

Water.  Protein.  Fat.  nitrogenous  ^,'", 

Matter.  ^^^"^''- 

White    .»     857  1 2  "6  o'25  —  0-59 

Yolk       ..     50'9  i6-2  3^75  o'i3  i'09 

One  can  see  at  a  glance  that  the  yolk  of  the  egg  is  much  its  most 
nourishing  part.  The  complexity  of  the  composition  of  the  yolk  is 
shown  by  the  following  more  detailed  analysis  of  its  constituents  :' 

^  For  more  recent  analyses,  which,  however,  do  not  differ  essentially  from  the 
above,  see  a  paper  by  Lebbin  on  the  Nutritive  Value  of  Eggs  in  the  Therap. 
Monatshefte,  1901,  xv.  552. 

^  Gobley,  quoted  by  Rottger,  'Lehrbuch  der  Nahrungsmittel  Chemie,'  p.  105. 
See  also  Juckenack,  Zeit.  /.  Untersuch.  d.  Nahrungsmittel,  1899,  xii.,  p.  905. 
Malcolm  ('  Note  on  the  Percentage  Composition  of  Egg-yolk, 'yo«>-«.  of  Physiol., 
1901,  xxvii.,  p.  356)  has  found  that  the  percentages  of  protein,  fat,  and  phos- 
phorus in  the  yolks  of  eggs  from  the  same  hen  do  not  vary  much,  whilst  there 
are  considerable  differences  in  eggs  from  a  number  of  hens  even  of  the  same 
breed.  The  percentage  of  lecithin  is  especially  subject  to  variations.  It  is 
probable  that  a  rich  reddish  yolk  contains  more  iron  than  one  which  is  of  a  pale 
yellow. 


COMPOSITION  OF  YOLK  OF  EGG 


153 


t.  Water      .,        „         , 

a.  Proteins  ( ^itejlin  15-8 

I  nuclein  . .  . .  . .         . ,       i  -5 

20-3 
0-4 
7-2 


51 -8  per  cent. 


Fats  (palmitin,  stearin,  and  olein) 
t  Cholesterol 

I  Lecithin            ..          ..          ..         ..         .,  ^  ^ 

(  Glycerin-phosphoric  acid 1-2 

Cerebrin 0-3 

Colouring  matter            ..         ..         ,,         ..  o"5 

Mineral  matters i-o 


These  different  constituents  are  not  merely  mixed  up  in  the  yolk, 
but  are  to  a  large  extent  actually  combined  with  one  another, 
producing  complex  bodies  which  chemists  have  not  yet  entirely 
succeeded  in  unravelling. 

Of  the  proteins  present,  the  nuclein  alone  calls  for  remark.  It  is 
of  importance  in  that  it  contains  phosphorus  in  organic  combination. 


SHILL  • CaRBONATI 
OF    LIMC   (6G"n^ 


Fig.  10.— Actual  Composition  of  an  Average 
Egg  weighing  50  grammes. 

Some  of  it  appears  also  to  be  united  to  iron  in  a  compound  to  be 
described  immediately. 

The  third  group  of  constituents — palmitin,  stearin,  and  olein — are 
simply  fats,  such  as  we  have  already  encountered  in  butter,  and 
have  the  same  nutritive  value  as  these.  Their  presence  in  the  form 
of  an  emulsion  in  the  yolk  makes  them  very  easily  digested. 

In  the  fourth  group  are  classed  together  a  number  of  substances 


154  FOOD  AND  DIETETICS 

which  are  of  great  interest,  and  give  to  the  yolk  of  egg  much  of  its 
peculiar  value  as  a  food.  They  are  often  included  among  the  fats  of 
the  yolk  for  the  reason  that,  like  these,  they  are  dissolved  out  by 
ether  ;  and  in  the  table  on  p.  152,  in  which  the  general  composition 
of  the  yolk  is  contrasted  with  that  of  the  white,  they  are  so  included. 
They  are,  however,  very  different,  chemically,  from  ordinary  fats. 
They  are  chiefly  characterized  by  containing  a  large  amount  of 
phosphorus  in  a  form  in  which  it  is  readily  absorbed  and  appropriated 
by  the  body.^  For  this  reason  these  substances  are  sometimes 
termed  phosphatides. ^ 

Cerebrin  is  a  glucoside  found  chiefly  in  nervous  tissues.  Its 
nutritive  value  is  unknown. 

The  most  important  of  the  mineral  matters  are  phosphoric  acid, 
lime,  and  iron.  According  to  Konig,  100  parts  of  the  ash  of  the 
white  and  yolk  of  egg  have  the  following  composition  respec- 
tively : 

Composition.  Yolk.  Whiti. 

Potassium        ••         ••         ..         ••         «.  9*29  3i'4i 

Sodium            ..         5'87  3i'57 

Lime <■        ..  I3'04  278 

Magnesium      ..         ..         ..         ..         ..  2*13  2*79 

Oxide  of  iron   ..          ..         ..         ..         ..  i"65  0*57 

Phosphoric  acid         ..         ..         ..         ..  65*46  4*41 

Sulphuric  acid            ..         ..         ..         ..  —  a"i2 

Fluorine           o"86  i*o6 

Chlorine           1*95  28*82 

The  phosphorus  of  the  yolk  is,  as  we  have  seen,  almost  entirely 
present  as  an  organic  compound.  The  same  is  true  of  the  iron, 
which  is  probably  united  with  nuclein.'  Now,  it  appears  to  be  a 
rule  in  physiology  that  mineral  matters  are  most  easily  absorbed 
when  they  form  part  of  an  organic  compound.  Hence,  the  iron 
in  the  yolk  of  egg  easily  enters  the  blood,  and  it  has  been 
found*  that  dogs  fed  largely  on  yolk  of  egg  excrete  far  more 
iron  in  the  urine  than  when  they  are  placed  on  ordinary  diet. 
One_  hundred   grammes  of  yolk  of  egg   contain   o"oi   gramme  of 

1  Hasebroek  has  shown  {Zeit.  f.  Physiolog.  Chemie,  1888.  xii.  148)  that  lecithin  is 
split  up  in  the  intestine  into  fatty  acids,  cholin  and  glycerin-phosphoric  acid. 
The  former  are  saponified  and  acquire  the  value  of  ordinary  fats  ;  the  cholin  is 
split  up  into  gases,  and  the  glycerin-phosphoric  acid  is  absorbed  unchanged. 
Cholesterol  is  probably  of  no  nutritive  value,  but  lecithin  appears  to  favour  the 
growth  of  young  animals  {Maly's  Jahres-Bericht  Thitr-Chemie,  1897,  xxvii.  615), 
and  may,  perhaps,  help  in  the  nutrition  of  the  nervous  system.  Lecithin  derived 
from  the  yolk  of  eggs  has  now  been  introduced  into  medicine  in  a  pure  form 
under  the  name  '  ovolecithin.' 

2  See  Thudichum's  '  Spirit  of  Cookery,*  p.  5S9. 

*  The  compound  is  sometimes  termed  a  '  baematogen,'  because  from  it  the 
colouring  matter  of  the  blood  of  the  chick  seems  to  be  formed. 

*  Bunge. 


COMPOSITION  OF  EGGS  155 

iron,*  and  as  the  yolk  of  one  egg  weighs  15  grammes,  it  will  yield 
0-0015  gramme  of  the  metal,  or  as  much  as  is  contained  in 
18  ounces  of  milk.  Assuming  that  10  milligrammes  of  iron  are 
required  by  the  human  body  daily  (Stockman),  seven  and  a  half 
eggs  will  suffice  for  the  supply  of  that  important  constituent  of  the 
blood.  Yolk  of  egg  must,  therefore,  be  regarded  as  a  useful  food 
for  anaemic  persoBS. 

The  abundance  of  calcium  in  the  yolk  is  very  striking.  No  food 
contains  so  much  of  it  except  milk.  It  is  probable  that  most  of 
these  lime  salts  are  also  present  in  organic  combination,  i.e.,  in  a 
very  assimilable  form. 

The  great  richness  of  yolk  of  egg  in  fat,  in  lime  salts,  and  in 
organic  compounds  of  phosphorus  and  iron,  make  it  a  peculiarly 
valuable  food  for  young  infants,  especially  those  which  are  suffering 
from  rickets,  for  it  is  just  those  very  compounds  which  a  child  needs, 
and  a  rickety  child  needs  them  most  of  all. 

Eggs  contain  no  free  purin  or  purin-yielding  substance,  and  may 
therefore  form  part  of  the  purin-free  diet  which  is  now  so  often 
recommended  in  gout. 

The  composition  of  the  whole  egg  may  be  summed  up  as  follows  :^ 

Shell    ..  Il"2  per  cent. 

Water 655 

Nitrogenous  matter ..         ..         ..         ..         ..  I3'i         ,, 

Fatty  matters  93        ,, 

Ash      ..         0-9        „ 

There  is  no  difference  in  composition  between  eggs  with  dark 
shells  and  eggs  with  white  shells,  and  no  justification  for  the  popular 
belief  that  the  former  are  '  richer '  than  the  latter.^ 

The  composition  of  the  edible  part  (white  and  yolk  together)  may 

be  compared  with  that  of  meat  thus  :* 

p.  Moderately 

^^^-  Lean  Meat. 

Water 737  73'o 

Protein 148  21*0 

Fat  10-5  5-5 

Ash  ro  I'o 

>  Socin,  Zei}.  f.  Physiolog.  Chemie,  i8gi,  xv.  93.  Hartung  {Zeit.  f.  Biologic, 
1902,  xliii.,  p.  195)  found  that  an  average  egg  contains  0-00435  gramme  of  oxide  of 
iron  in  100  grammes  of  substance  (white  and  yolk  together).  The  yolk  is  ten 
times  richer  in  the  metal  than  the  white. 

-  Atwater,  'Composition  of  American  Food  Materials,'  Bulletin  28,  United 
States  Department  of  Agriculture  (revised  edition).  The  percentage  of  shell  is 
somewhat  lower  than  that  given  on  p.  151). 

*  See  '  Eggs  and  their  Uses  as  Food,'  by  C.  F.  Langworthy,  Farmers'  Bulletin, 
No.  128,  United  States  Department  of  Agriculture,  1901. 

*  Atwater,  '  Composition  of  American  Food  Materiads,'  Bulletin  28  (average  of 
•ixty  analyses). 


156 


FOOD  AND  DIETETICS 


One  sees  at  a  glance  that  eggs  contain  almost  the  same  total  of 
nutritive  matter  as  meat,  but  are  relatively  richer  in  fat  and  poorer 
in  protein. 

Eggs  are  thus  admirably  adapted  chemically  to  supplement  a 
food  rich  in  carbohydrate,  moderately  rich  in  protein,  but  poor  in 
fat.  Such  a  food  is  found  in  rice  and  many  cereals,  and  the  addition 
of  eggs  to  these  in  the  form  of  puddings  makes  a  complete  food.  We 
have  here  another  instance  in  which  ancient  experience  and  practice 
are  justified  by  modern  science. 

The  composition  of  a  goose's  or  duck's  egg  is  very  similar  to  that 
of  the  hen,  but,  of  course,  they  are  larger.  An  average  duck's  egg 
weighs  about  2^  ounces,  a  goose's  egg  from  5^  to  6^  ounces. 

THE  COMPOSITION  OF  EGGS.i 


Refuse. 

Water. 

Protein. 

Fat. 

Ash. 

Per  Cent. 

Per  Cent. 

Per  Cent. 

Per  Cent. 

Per  Cent. 

Hen: 

Whole  egg  as  purchased     . . 

II'2 

65-5 

II-9 

93 

0-9 

Whole  egg,  edible  portion  . . 

— 

737 

13-4 

IO-5 

I'O 

White 

— 

862 

12-3 

0-2 

06 

Yolk 

— 

49*5 

157 

33  3 

II 

Duck: 

Whole  egg  as  purchased 

137 

60 -8 

I2-I 

12-5 

0-8 

Whole  egg,  edible  portion  . . 

— 

70-5 

13-3 

14-5 

10 

White 

— 

byo 

III 

0-03 

08 

Yolk 



45-8 

i6-8 

362 

1-2 

Turkey : 

Whole  egg  as  purchased 

13-8 

63-5 

12-2 

97 

08 

Whole  egg,  edible  portion  . . 

— 

737 

13-4 

1 1 -2 

09 

White 

— 

867 

"■5 

0*03 

0-8 

Yolk 

— 

48-3 

174 

32-9 

1-2 

Plover : 

Whole  egg  as  purchased     . . 

9-6 

67-3 

97 

IO-6 

09 

Whole  egg,  edible  portion  . . 

— 

74*4 

107 

117 

i-o 

Guinea  fowl : 

Whole  egg  as  purchased     . . 

i6-g 

60-5 

II-9 

9-9 

0-8 

Whole  egg,  edible  portion  . . 

— 

72-8 

13-5 

12  0 

0-9 

White 

— 

86-6 

II-6 

003 

0-8 

Yolk 

— 

497 

167 

31-8 

1-2 

When  kept,  eggs  gradually  lose  water  by  evaporation  and  become 
lighter.  A  fresh  egg  should  sink  at  once  in  a  10  per  cent,  salt 
solution  (about  2  ounces  to  a  pint),  but  the  longer  it  has  been  kept 
the  nearer  the  surface  it  will  float. 

When  an  egg  becomes  rotten,  alkaline  sulphides  are  produced, 
apparently  from  the  white,  and  these  being  acted  upon  by  phosphoric 
acid   derived   from   the   yolk,    sulphuretted   hydrogen  is  liberated, 

*  United  States  Department  of  Agriculture,  Farmers'  Bulletin,  No.  234. 


DIGESTIBILITY  OF  EGGS  157 

which  gives  to  a  rotten  egg  its  very  disagreeable  smell.     If  an  egg 

is  boiled   for  a  long  time  the  same  effect  is  produced  in  a  minor 

degree,  and  it  is  well  known  that  an  egg  so  treated  is  apt  to  have  a 

slight  odour. 

The  digestibility  of  eggs  in  the  stomach  depends  largely  upon  the 

form  in  which  they  are  taken.     Some  experiments  have  been  made 

on  a  healthy  man  which  throw  light  on  this  subject.^     Two  eggs 

were  given,  cooked  in  different  ways,  and  portions  of  the  stomach 

contents  were  withdrawn  at  intervals,  the  time  being  noted  at  which 

any  portion  of  egg  ceased  to  be  recovered.     The  results  were  as 

follows : 

2  eggs  lightly  boiled  have  left  the  stomach  in  if  hours 

„      raw  have  left  the  stomach  in      ..  ..  ..  ..         ••  2^     „ 

„     poached  +  5  grammes  of  butter  have  left  the  stomach  in     . .  2^     „ 

„     hard  boiled  have  left  the  stomach  in    . .         . .         . .         •  •  3      „ 

„     as  an  omelette  have  left  the  stomach  in  . .         . .         . .  3      n 

The  figures  speak  for  themselves.  One  or  two  points,  however, 
call  for  comment.  It  is  surprising  to  find  that  lightly  boiled  eggs 
are  more  quickly  disposed  of  by  the  stomach  than  eggs  given  raw. 
One  must  take  care,  however,  not  to  jump  to  the  conclusion  that 
lightly  boiled  eggs  are  more  suited  to  a  stomach  requiring  rest  than 
raw  eggs  are.  As  a  matter  of  fact,  raw  egg  seems  to  be  scarcely 
digested  in  the  stomach  at  all,  but  passed  on  out  of  it  to  a  large 
extent  unchanged.  Some  observations  bearing  upon  this  point 
were  made  on  a  patient  in  whom,  as  the  result  of  disease,  an 
artificial  opening  had  formed  into  the  intestine  a  very  short  distance 
below  the  point  at  which  it  joins  the  stomach.^  It  was  found  that 
when  raw  egg  was  given  by  the  mouth  more  than  half  of  it 
ultimately  escaped  by  this  opening  unchanged.  The  explanation 
may  perhaps  be  that  raw  egg  is  such  a  bland  fluid  that  it  does  not 
excite  the  secretion  of  gastric  juice  nor  the  movements  of  the  stomach. 
Hence  it  may  linger  longer  in  the  stomach  than  an  egg  which  has 
been  lightly  boiled,  because  the  solid  particles  of  the  latter  stimulate 
both  secretion  and  movement.  The  raw  egg  is  thus  really  the  less 
irritating  to  the  stomach  of  the  two,  and  makes  less  demand  upon 
it,  for  its  digestion  is  really  performed  in  the  intestine. 

The  difference  in  digestibility  between  hard  and  soft  boiled  eggs 
depends  to  some  extent,  also,  on  the  degree  to  which  the  former  are 
subdivided.  If  finely  chopped  up,  they  could  probably  be  disposed 
of  as  easily  as  the  soft-boiled  eggs.^ 

1  Penzoldt,  Deut.  Arch.  f.  Klin.  Med.,  1893,  li-,  P  535- 

*  Busch,  Virchow's  Arckiv,  1858,  xiv.,  p.  140. 

'  A  great  many  observations  have  shown  that  the  white  of  one  egg  finely 
chopped  and  taken  with  2^  ounces  of  water  remains  in  the  stomach  for  one  and 
•  quarter  hours  (Jaworski  and  Gluzinski,  Zeit.  f.  Klin.  Med.,  1886,  xi.  84). 


158  FOOD  AND  DIETETICS 

I  am  not  acquainted  with  any  experiments  on  the  relative 
digestibility  of  the  white  and  yolk  of  egg,  but  one  would  expect  the 
latter,  owing  to  its  larger  proportion  of  solids  and  great  richness  in 
fat,  to  be  more  slowly  dissolved  in  the  stomach  than  the  white. 

It  must  also  be  pointed  out  that  idiosyncrasy  plays  a  large  part  in 
the  digestion  of  eggs.  Some  persons  are  unable  to  swallow  even  a 
small  particle  of  egg  without  becoming  violently  ill,  the  symptoms 
ranging  from  slight  urticaria  to  vomiting,  syncope,  and  coma. 
Apparently  their  digestive  juices  act  on  the  egg  in  such  a  way  as  to 
produce  poisons  from  it.*  In  other  cases  sulphuretted  hydrogen 
seems  to  be  produced  during  the  digestion  of  the  egg.  As  the  table 
on  p.  154  shows,  the  sulphur  of  the  egg  is  confined  almost  entirely  to 
the  white.  That  part  should,  therefore,  be  specially  avoided  in  such 
conditions. 

The  absorption  of  eggs  in  the  intestine  seems  to  be  very  complete. 
It  has  been  found  that  even  when  21  hard-boiled  eggs  are  taken  daily 
they  are  absorbed  as  completely  as  meat,  only  5  per  cent,  of  the 
dried  substance  being  lost.* 

Eggs,  therefore,  leave  a  very  small  residue  in  the  intestine.  This, 
coupled  with  the  fact  that  they  contain  so  much  lime,  may  perhaps 
explain  their  constipating  effect  on  some  persons. 

Chemical  considerations  have  shown  us  that  the  nutritive  value  of 
eggs  is  due  almost  entirely  to  protein  and  fat.  One  egg  contains 
enough  of  these  to  yield  70  Calories  of  energy.  Half  a  tumblerful  of 
good  milk  or  i^  ounces  of  fat  meat  would  yield  about  as  much. 

Roughly  speaking,  15  to  20  eggs  may  be  taken  as  the  nutritive 
equivalent  of  2  pounds  of  medium  fat  meat. 

The  absence  of  carbohydrates  prevents  eggs  from  being  in  any 
sense  a  complete  food,  and  it  would  require  20  of  them  a  day  to 
supply  even  the  amount  of  nitrogen  required  by  a  healthy  man. 
They  cannot  be  regarded  as  a  cheap  source  of  protein,  though 
the  convenient  form  in  which  their  nutritive  constituents  are  pre 
sented,  and  the  readiness  with  which  they  lend  themselves  to  the 
art  of  the  cook,  must  always  render  them  a  most  useful  form  of  food. 
In  addition  to  these  considerations,  the  peculiar  chemical  composition 
of  the  yolk  causes  that  part  of  the  egg  to  be  a  valuable  source  of 

i  For  illustrative  cases,  see  Med.  and  Surg.  Review,  1899,  ii.  299,  and  L'Echo 
Med.  du  Nord,  August  13,  1905  (Abstract  in  Med.  Rev.,  1905,  viii.  586).  Also  a 
case  described  by  A.  T.  Schofield  {Lancet,  1908,  i.  716)  in  wliich  he  succeeded 
in  establishing  tolerance. 

*  Rubner,  Zeit.  f.  Biologic,  1879,  xv.,  p.  115.  For  an  account  of  more  recent 
experiments,  which,  however,  yielded  almost  identical  results  with  Rubner's,  see 
Farmers'  Bulletin,  No.  128,  p.  17,  United  States  Department  of  Agriculture,  and 
Aufrecht  and  Sinaon,  Deut.  Med.  Woch.,  1908,  xxxiv.  2309. 


C  USTA  RD-PO  WDERS 


159 


phosphorus,  lime  and  iron,  of  which  advantage  may  well  be  taken  in 
the  dietetic  treatment  of  certain  diseases,  more  especially  of  early  life. 

There  are  but  few  artificial  preparations  of  eggs.  Eggo  consists 
of  yolks  of  eggs  dried  at  a  low  temperature,  so  that  they  are  capable 
of  being  redissolved.  It  is  a  convenient  form  in  which  to  keep  eggs 
for  cooking  purposes. 

Condensed  eggs  prepared  by  evaporation  in  vacuo,  either  with  or 
without  the  addition  of  sugar,  are  also  obtainable  for  a  similar 
purpose. 

Custard -powders  are  sold  as  '  substitutes  '  for  eggs.  The  majority 
of  them  consist  chiefly  of  starch,  to  which  a  yellow  colour  is  im- 
parted by  mixture  with  some  vegetable  dye — e.g.,  turmeric.  The 
following  analyses  of  some  of  them  were  published  in  Food  and 
Sanitation  (November  25,  1893) : 


Bird's 
Custard- 
powder. 

Goodall's 
Custard- 
powder. 

Goodall's 

Egg- 
powder. 

Berwick's 

Egg- 
powder. 

Yeatman's 

Egg- 
powder. 

'  Model' 

Egg- 
powder. 

Starch 

Albuminous  com- 
pounds . , 

S  ol  uble  colouring 
matter    . . 

Baking  soda 

Tartaric  acid 

Phosphates 

Carbonates  of  lime  and 
magnesia 

Chlorides  and  sulphates 

Water 

Ash          

86-25 

0-59 

0-88 

11-83 

0-45 

84-45 
0-58 
0-90 

13-69 
0-38 

5 1  "03 
6-01 

15-33 

13  69 

0-24 

2-70 

ii-o 

26-38 
2-96 

50-70 
io-33 

9 '63 

52-32 
6-00 

22-11 
11-37 

8-20 

53-82 
506 

26-71 
6-19 

traces 
8-22 

100 -oo 

100-00 

100 -oo 

100 -oo 

100-00 

100  00 

It  is  obvious  that  they  have  nothing  in  common  with  eggs  except 
a  yellow  colour,  and  that  their  nutritive  value  can  be  in  no  way 
equal  to  that  of  a  genuine  custard. 


[  i6o] 


CHAPTER  X 

VEGETABLE  FOODS 

The  foods  with  which  we  have  been  deaUng  up  till  now  are  derived 
from  the  animal  kingdom.  In  the  present  chapter  we  approach  the 
study  of  that  large  and  varied  class  of  foods  which  we  obtain  from 
vegetable  sources.  We  may  consider  in  the  first  place,  in  a  general 
way,  the  chemical  composition,  digestibility  and  nutritive  value  of 
the  vegetable  foods  as  a  whole,  contrasting  them  in  these  respects 
and  in  their  economic  aspects  with  foods  of  animal  origin,  and  then 
proceed  to  the  detailed  study  of  the  different  groups  into  which 
vegetable  foods  may  be  subdivided. 

1.  Chemical  Composition  of  Vegetable  Foods. 

From  a  chemical  point  of  view,  the  most  striking  feature  of  the 
vegetable  foods  is  the  large  proportion  of  carbohydrates  which  they 
contain.  This  peculiarity  marks  them  off  at  once  from  the  animal 
foods,  for  the  latter,  with  a  few  exceptions,  such  as  milk,  contain 
little  or  no  carbohydrate  at  all.  Richness  in  protein  and  fat  is  the 
characteristic  of  animal  foods,  abundance  of  sugar  and  starch  that 
of  the  products  of  the  vegetable  kingdom. 

Now,  starch  is  by  no  means  such  a  concentrated  form  of  carbon 
as  fat  is.  Indeed,  it  takes  221  parts  of  starch  to  be  equal  to  100 
parts  of  fat.  This  is  one  reason  why  vegetable  foods  must  be  re- 
garded as  dilute  ajid  bulky,  while  animal  food  is  concentrated  and 
compact. 

But  vegetable  foods  possess  not  merely  abundance  of  carbo- 
hydrates :  they  contain  proteins  and  fats  as  well.  Some  members  of 
the  class,  such  as  the  pulses,  are  peculiarly  rich  in  the  former  ;  others, 
such  as  nuts,  in  the  latter ;  but  of  vegetable  foods  as  a  whole  it  may 
be  said  that  more  than  the  animal  foods  they  contain  representa- 
tives of  all  the  three  groups  of  nutritive  substances.     In  consider- 


VEGETABLE  FOODS  i6i 

ation  of  this  fact,  the  vegetable  kingdom  must  be  pronounced  a  better 
source  of  human  food-supply  than  the  animal,  and  if  one  were 
confined  in  his  selection  of  a  dietary  exclusively  to  one  kingdom  or 
the  other,  it  would  be  wiser  to  patronize  the  miller  and  greengrocer 
rather  than  the  butcher  and  fishmonger,  for  it  is  undoubtedly  possible 
to  live  on  vegetables  alone,  whereas  it  is  difficult  to  live  for  any 
length  of  time  on  nothing  but  meat.  The  better  way  for  most 
people,  however,  is  to  avail  themselves  of  the  resources  of  both 
kingdoms. 

It  is  now  necessary  that  we  should  consider  for  a  moment  in 
somewhat  greater  detail  the  different  groups  of  nutritive  substances 
which  enter  into  the  composition  of  the  vegetable  foods. 

Of  the  carbohydrates  we  have  already  mentioned  sugar  and  starch. 
Sugar  is  the  form  in  which  carbohydrate  circulates  in  plants ;  starch 
is  the  shape  in  which  it  is  stored  up.  If  a  plant  has  manufactured 
more  carbohydrate  than  it  requires  for  its  present  purposes,  it  puts 
aside  the  surplus  in  the  shape  of  starch,  and  when  the  pinch  of  need 
comes  upon  it,  and  it  requires  a  supply  of  carbohydrate  again  to 
maintain  its  fife,  some  of  this  store  of  starch  is  changed  back  into 
sugar  by  the  help  of  the  ferment  diastase,  and  circulates  once  more 
throughout  the  plant.  Sugar,  then,  is  the  soluble  form  of  carbo- 
hydrate :  it  is  carbohydrate  in  circulation,  and  corresponds  to  the 
current  coin  in  our  pocket  ;  starch  is  the  insoluble  form  of  carbo- 
hydrate :  it  is  carbohydrate  in  reserve,  and  corresponds  to  the  bullion 
in  the  bank.  It  is  important  to  grasp  this  mutual  convertibility  of 
starch  and  sugar.  We  shall  see  later  that  a  precisely  analogous 
process  goes  on  in  the  animal  body,  and  that  all  the  starch  which  we 
eat  must  first  be  converted  by  digestion  into  sugar  before  it  can 
circulate  through  our  bodies  and  be  available  as  food. 

A  heap  of  starch  is  really  made  up  of  minute  grains,  just  as  a  heap 
of  sand  is,  but  the  starch  grains  are  much  smaller  than  those  of  sand, 
and  can  only  be  seen  with  the  aid  of  a  microscope.  When  so 
examined,  they  will  be  observed  to  have  various  shapes,  round,  oval 
or  polyhedral,  depending  on  the  plant  from  which  the  starch  is 
derived.  They  also  exhibit  concentric  markings.  These  indicate 
that  the  starch  grain  is  built  up,  like  a  sandwich,  of  different  layers. 
One  set  of  layers  consists  of  true  starch  (amylose  or  granulose) ;  the 
other  set  consists  of  a  form  of  cellulose,  formerly  known  as  starch 
cellulose  or  farinose.  The  outer  layers  of  the  starch  grain  are  the 
densest,  and  the  most  external  one  of  all  seems  to  consist  entirely  of 
starch  cellulose. 

These  little  starch  grains  are  not  dissolved  by  cold  water.     This 

II 


i69  FOOD  AND  DIETETICS 

is  one  reason  why  starch  is  the  form  in  which  plants  stoWaway  theiT 
surplus  carbohydrate ;  being  insoluble,  there  is  no  risk  of  its  being 
all  washed  away  by  rain  if  the  plant  gets  injured.  Another  reason 
is  that  starch  is  a  more  concentrated  form  of  carbohydrate  than 
sugar,  and  packs  into  a  smaller  bulk. 

If  boiling  water  be  poured  on  the  grains,  they  swell  up  and  burst, 
and  the  true  starch  escapes  from  between  the  layers  of  cellulose,  and 
forms  with  the  water  the  gelatinous  solution  familiar  to  the 
laundress. 

It  is  this  rupture  of  the  starch  grains  that  we  seek  to  bring  about 
by  the  cookery  of  vegetable  foods,  for  one  can  readily  imagine  that 
starch  grains  which  have  been  thus  broken  up  and  brought  into 
solution  will  be  much  more  easily  attacked  by  the  digestive  juices, 
and  converted  into  sugar,  than  when  eaten  in  their  raw  and  un- 
ruptured state. 

If  starch  be  subjected  to  dry  heat,  it  undergoes  a  modification  by 
which  it  becomes  soluble  in  water,  and  is  ultimately  converted  (at  a 
temperature  of  about  300°  F.)  into  the  form  of  carbohydrate  known 
as  dextrin.  This  is  a  gummy  substance,  and  is  familiar  to  everyone 
as  the  sticky  material  on  the  backs  of  postage  stamps.  This  change 
also  takes  place  to  some  extent  in  cookery.  The  crust  of  a  loaf 
of  bread,  for  example,  consists  mainly  of  starch  which  has 
been  converted  by  the  heat  of  the  oven  into  soluble  starch  and 
dextrin. 

We  saw  that  in  the  case  of  meat  the  nutritive  ingredients  (proteins) 
were  contained  in  minute  tubes  held  together  by  a  connective  tissue 
which  yields  gelatin.  In  the  case  of  most  vegetable  foods,  on  the 
other  hand,  the  chief  nutritive  ingredient  (starch)  is  contained  in  a 
vast  number  of  minute  compartments,  more  or  less  cubical  in  shape, 
and  collectively  known  as  '  cells.'  The  walls  of  these  and  the 
framework  which  holds  all  the  cells  together  are  composed  of 
a  substance  known  as  cellulose,  the  most  familiar  form  of  which 
is  paper. 

Now,  cellulose  also  belongs  to  the  carbohydrate  group,  but  it  is 
especially  characterized  by  its  extraordinary  insolubility.  Neither 
cold  nor  hot  water  has  any  effect  upon  it,  and  in  order  seriously  to 
influence  it  one  must  boil  it  with  a  dilute  acid.  In  its  old  age  cellu- 
lose gets  infiltrated  with  resinous  matter  and  becomes  wood  ;  it  is 
then  past  the  stage  of  being  much  affected,  even  by  acids.  The 
presence  of  cellulose  in  nearly  all  forms  of  vegetable  food  is  a  fact 
of  great  practical  importance  when  one  considers  that  it  encloses  the 
starch  grains  in  the  vegetable  cell,  much  in  the  same  way  as  a  sheet 


STARCH  AND  CELLULOSE  163 

of  brown  paper  encloses  a  parcel  of  oranges,  and  when  one  remembers 
its  peculiar  insolubility  it  becomes  obvious  at  once  that  this  wall  of 
cellulose  must  present  a  great  obstacle  to  that  penetration  of  the 
nutritive  ingredients  by  the  digestive  juices  which  is  of  the  first 
importance  for  the  proper  carrying  out  of  digestion. 

In  addition  to  starch  and  cellulose,  there  is  another  and  peculiar 
group  of  carbohydrates  met  with  in  vegetable  foods,  the  members 
of  which  are  spoJcen  of  by  some  writers  as  pectin  bodies,  while 
others  class  them  together  under  the  general  term  '  pectose.' 
These  are  the  substances  which  give  to  fruits  their  power  of  form- 
ing jellies  when  boiled,  and  little  is  known  of  their  exact  chemical 
nature,  but  they  appear  to  be  converted  into  a  special  kind  of  sugar 
when  digested  (pentose),  which  is  at  least  partly  assimilable  by  the 
body.* 

The  last  group  of  carbohydrates  which  occur  in  vegetable  foods 
are  the  sugars  of  which  brief  mention  has  already  been  made.  Their 
importance  as  foods  is  such  as  to  merit  a  more  detailed  consideration 
later  (see  Chap.  XV.). 

The  nitrogenous  substances  met  with  in  vegetable  foods  may  be 
divided,  as  in  the  case  of  meat,  into  those  which  are  proteins  and 
those  which  are  not.  The  vegetable  proteins  belong  mainly  to  the 
globulin  class.  These  are  easily  dissolved  by  water  containing  a 
httle  salt,  and  may  be  lost  to  an  appreciable  extent  from  vegetables 
which  are  left  soaking  in  such  a  mixture.  It  should  be  mentioned, 
also,  that  vegetable  foods  contain  less  of  the  substances  known  as 
nucleo-proteins  than  one  meets  with  in  animal  tissues.  The  practical 
importance  of  this  will  be  pointed  out  when  we  come  to  consider  the 
dietetics  of  gout. 

Both  varieties  of  protein,  vegetable  as  well  as  animal,  are 
coagulated  by  heat,  and  both  are  rendered  less  digestible  thereby. 
The  broad  result  is  that  cooking  diminishes  the  digestibility 
of  animal  foods,  because  they  are  mainly  composed  of  protein, 
but  raises  the  digestibility  of  vegetable  foods  because  the  latter 
contain,  as  a  rule,  very  little  protein  along  with  much  starch, 
and  cooking,  as  we  have  seen,  renders  starch  much  more  easy  of 
digestion. 

1  Some  of  these  bodies  appear  to  be  of  the  nature  of  dextrins,  vshilst  others, 
perhaps,  stand  nearer  to  starch.  It  might  be  well  to  restrict  the  term  'pectins  ' 
to  the  former  group :  they  probably  bear  the  same  relation  to  the  pentoses,  or 
sugars  with  five  carbon  atoms,  that  dextrin  does  to  the  six-carbon-atom  sugar, 
dextrose.  The  other  group  may  be  spoken  of  as  pentosanes.  The  sugars  to 
which  they  give  rise  are  also  found  fn  many  ripe  fruits,  and  are  certainly  not  easily 
assimilated  by  the  cells  of  the  body,  and  are  apt  to  appear  in  the  urine  if  the  fruits 
containing  them  are  eaten  in  excess. 


i«4  FOOD  AND  DIETETICS 

Vegetable  foods  resemble  animal  foods  in  containing  a  large 
number  of  nitrogenous  substances  which  are  in  no  sense  proteins. 
None  of  these,  however,  corresponds  in  any  way  to  the  '  albu- 
minoids'  {e.g.,  gelatin)  met  with  so  abundantly  in  the  animal 
kingdom. 

On  the  other  hand,  extractives  are  well  represented.  Most  of 
these  belong  to  the  group  of  chemical  substances  called  '  amides.' 
Asparagin,  which  is  richly  present  in  the  potato,  is  one  of  the  best 
known.  Its  uses  as  an  ingredient  of  the  food  will  be  considered 
when  we  deal  with  the  potato. 

Of  the  fats  found  in  vegetable  foods  little  need  be  said.  They 
resemble  in  chemical  composition  the  animal  fats,  but  appear  to 
contain,  as  a  rule,  more  of  the  oily  constituent  (olein)  and  less  of  the 
more  solid  components  (stearin  and  palmitin)  than  the  fat  of  animals. 
Hence  they  tend  to  have  the  consistency  of  oils  rather  than  of  solid 
fats.  This,  however,  increases  rather  than  lessens  their  digestibility, 
while  their  nutritive  value  seems  to  be  fully  equal  to  that  of  the 
more  solid  animal  fats. 

The  remaining  chemical  constituents  of  vegetable  foods  are  water 
and  certain  mineral  salts.  There  is  an  extraordinary  amount  of  water 
present,  much  more  than  one  is  inclined  to  fancy.  Even  green  peas 
and  lentils,  which  are  the  richest  in  solid  constituents  of  the  commoner 
vegetable  foods,  contain  78  per  cent,  of  water,  while  in  green  vege- 
tables and  most  fruits  water  accounts  for  more  than  90  per  cent,  of 
the  weight  of  the  fresh  food.  This  means  that  a  cabbage  is  really  a 
more  watery  form  of  food  than  milk,  for  the  latter  only  contains  87 
per  cent,  of  water.  The  apparent  solidity  of  green  vegetables  is 
deceptive,  and  is  merely  due  to  the  framework  of  cellulose  which 
supports  them. 

This  wateriness  of  most  vegetable  foods  is  one  of  their  most 
essential  properties,  and  is  mainly  responsible  for  the  low  nutritive 
value  of  many  of  them  when  compared  with  the  largeness  of  their 
bulk.  Unfortunately,  also,  most  vegetable  foods  become  even  more 
watery  when  subjected  to  the  process  of  cooking ;  their  last  state  is 
thus  worse  than  their  first,  whereas  in  the  case  of  animal  foods  the 
contrary  is  the  case. 

Attempts  have  been  made,  and  with  a  large  amount  of  success,  to 
reduce  the  bulk  of  vegetable  foods  by  removing  the  water  which  they 
contain.  As  early  even  as  the  middle  of  last  century  a  patent  was 
taken  out,  by  a  certain  Mr.  Masson,  for  effecting  this  by  a  process 
of  drying.     His  method  enabled  him  to  put  up  70  pounds  weight  of 


ABSORPTION  OF  VEGETABLE  FOODS  165 

cabbage  in  a  tin  of  11  pounds.  In  recent  years  several  processes 
effecting  the  same  object  have  been  introduced,  with  the  result 
that  one  can  obtain  all  the  commoner  vegetable  foods  in  a 
remarkably  compact  form,  and  yet  without  the  sacrifice  of  any 
of  their  nutritive  ingredients  or  flavour.  The  conveniences  of 
this  in  the  case  of  military  transport  and  camping  expeditions 
are  obvious. 

The  mineral  constituents  of  vegetable  foods  are  numerous  and 
important.  Further  reference  will  be  made  to  them  when  the 
different  groups  of  vegetable  foods  are  dealt  with  separately,  but 
at  present  one  may  point  out  that  potash  is  in  most  of  them  more 
abundantly  represented  than  soda.  This  has  been  alleged  by  a 
distinguished  physiologist  (Bunge)  as  the  reason  why  herbivorous 
animals  have  a  craving  for  sodium  in  the  form  of  common  salt 
(sodium  chloride). 

A  large  proportion  of  the  bases  amongst  the  mineral  ingredients 
of  vegetable  foods  are  united  with  organic  acids,  and  these,  when 
burnt  up,  either  outside  or  inside  the  body,  yield  alkaline  salts.  The 
excretion  of  these  in  the  urine  causes  it  to  have  a  less  degree  of 
acidity  in  vegetable  than  animal  feeders,  and  is,  as  we  shall  see, 
turned  to  therapeutic  account  in  the  case  of  those  who  are  suffering 
from  stone  or  gravel. 


a.  Digestibility  and  Absorption  of  Vegetable  Foods. 

1.  In  the  Stomach. — As  a  class,  vegetable  foods  are  not  to  any 
large  extent  really  digested  in  the  stomach,  because  starch,  their 
chief  ingredient,  is  entirely  unaffected  by  the  gastric  juice.  Hence 
it  follows  that  it  is  only  those  vegetable  foods  which  are  particularly 
rich  in  protein,  such  as  the  pulses,  which  throw  upon  the  stomach 
any  large  share  of  the  chemical  part  of  their  digestion.  On  the  other 
hand,  the  manipulation  of  bulky  vegetable  food,  its  reduction  to  a 
state  of  fine  division,  and  the  passing  of  it  on  into  the  intestine,  all 
entail  upon  the  stomach  a  large  amount  of  mechanical  effort.  As  a 
consequence  of  this,  animal  food,  which  necessitates  for  its  digestion 
more  chemical  but  less  mechanical  work  on  the  part  of  the  stomach, 
is  really  better  borne  by  persons  of  enfeebled  digestive  power  than 
the  majority  of  vegetable  foods  are. 

2.  In  the  Intestine. — It  is  customary  to  state  that  vegetable  foods 
are   less   completely  digested   and   absorbed  in  the  intestine  than 


i66 


FOOD  AND  DIETETICS 


animal  foods.  Stated  in  such  general  terms,  the  proposition  cannot 
be  substantiated.  It  depends  entirely  on  the  form  of  vegetable  food. 
A  glance  at  the  table  will  show  that  the  foods  which  are  the  most 
completely  digested  and  absorbed  of  all  (white  bread,  macaroni, 
and  rice)  are  vegetable  foods,  while  meat  and  eggs  rank  distinctly 
after  these. 

RELATIVE  ABSORPTION  OF  SOME  ANIMAL  AND  VEGETABLE 

FOODS.* 


Pood. 


Dry  Substance 
not  Ahs.^rbed. 
White  bread     ..         ..     4  per  cent. 
Macaroni  ..         ••4 

Rice        ..         ..  ••4 

Meat 4^ 

Eggs 4i 

Maize     ..         ..         ••     7 


Food, 


Milk 

Peas        . .  . , 

Potatoes 

Black  bread  ..          • .    15 

Cabbage  ..          ••    15 

Turnips  . .  ,.          ..2c 


Dry  Substance 
not  Absorbed 
9  per  cent. 
9 


Two  factors  appear  to  determine  the  digestibility  of  vegetable 
foods  in  the  intestine.  The  first  is  their  bulk  ;  the  second  is  the 
amount  of  cellulose  which  they  contain.  If  the  bulk  be  small  and 
the  "proportion  of  cellulose  scanty,  digestion  is  very  complete. 
White  bread,  macaroni,  and  rice  fulfil  these  conditions,  hence  the 
small  proportion  of  them  which  escapes  absorption.  On  the  other 
hand,  if  the  food  be  bulky  and  full  of  cellulose,  digestion  and  absorp- 
tion are  much  less  perfect.  Unfortunately,  the  majority  of  vegetable 
foods  more  or  less  correspond  to  this  description,  and  hence  the 
proposition  as  originally  laid  down  is  true  of  the  majority  of  them, 
namely,  that  they  are  not  so  completely  digested  and  absorbed  as 
animal  foods  are. 

The  property  of  bulkiness  is  one  common  to  the  majority  of 
vegetable  foods.  As  already  indicated,  it  is  to  be  attributed 
in  a  great  measure  to  the  amount  of  water  and  starch  which 
they  contain.  Considering  that  upwards  of  four  -  fifths  of  the 
weight  of  all  green  vegetables  and  fruits  is  due  to  water,  and  that 
even  the  drier  forms,  such  as  split  peas,  take  up  about  three  times 
their  weight  of  water  in  the  process  of  cooking, ^  it  is  not  to  be 
wondered  at  that  vegetable  foods  must  be  bulky  out  of  all  proportion 
to  the  amount  of  nutriment  which  they  contain.  To  this  rule  bread 
is  almost  the  sole  exception,  containing  as  it  does  fifty-six  parts  of 
dry  matter  in  every  hundred.  Hence,  bread  must  of  necessity  enter 
largely  into  any  purely  vegetarian  diet  if  the  bulk  of  the  latter  is  to 

*  Compiled  from  the  figures  of  Voit,  Zeit.  j.  Biolog.,  1889,  xxv.  232. 

'  Half  a  pound  of  split  peas  boiled  to  a  thick  porridge  weighs  2  pounds. 


ABSORPTION  OF  VEGETABLE  FOODS 


167 


8  00 


ANIMAL 


1300 


MIXED 


be  kept  within  reasonable  limits.  Even  then  a  vegetable  diet 
remains  of  much  larger  volume  than  a  purely  animal  or  even  a 
mixed  diet.  The  diflference  is  graphically 
brought  out  in  Fig.  11,  where  the  bulk 
of  an  equivalent  amount  of  each  kind  of 
diet  is  exhibited  in  proper  relative  pro- 
portion.^ 

This  bulkiness  of  vegetable  food  inter- 
feres with  its  digestion  in  two  ways. 
First,  it  is  diflficult  for  the  digestive  juices 
thoroughly  to  penetrate  such  a  mass,  hence 
the  conversion  of  the  nutritive  constituents 
into  forms  suitable  for  absorption  is  apt  to 
be  inefficiently  carried  out  ;  secondly,  the 
large  bulk  of  food  stimulates  and  hastens 
the  movements  of  the  intestine,  and  the 
contents  of  the  latter  are  thus  hurried  on, 
and  less  time  allowed  for  absorption  to 
take  place.  It  is  to  compensate  for  this 
VEGETABLE  ^'j^q^  herbivorous  animals  have  a  much 
longer  intestine  than  the  carnivora. 
Fig.  II.— Relative  Bulks  The  other  great  obstacle  to  the  complete 
OF  AN  Animal,  a  Mixed,  digestion  and  absorption  of  vegetable  foods 
AND  A  Vegetable  Diet  (in   •     ,1      •    .      ,•       •     ^1  r       ,,   , 

Cubic  Centimetres).  ^^  '"®  mtestme  is  the  presence  or  cellulose. 

The  reasons  for  this  have  been  already  to 
some  extent  explained  (p.  162).  Cellulose  is  very  imperfectly 
attacked  by  the  digestive  apparatus  of  man  and  other  carnivorous 
animals.  Indeed,  only  while  it  is  still  very  young  and  tender  is  it 
capable  of  solution  to  any  extent. ^  In  this  condition  an  amount 
varying  from  4  up  to  60  per  cent,  or  so  of  the  cellulose  in  the  food 
may  disappear  in  the  course  of  digestion. ^  But  it  is  exceedingly 
doubtful  whether  even  this  amount  is  really  made  use  of  as  food. 
Part  at  least  of  it  seems  to  be  converted  by  the  action  of  bacteria 
into  marsh  gas  and  lost  to  the  body.* 

'  See  Voit,  Zeit.  f.  Biolog.,  1889,  xxv.  23a. 

'  Meyer,  Zeit.  f.  Biolog.  1871,  vii.  r. 

»  Atwater  has  constructed  a  table  (p.  168)  showing  the  degree  to  which  cellulose 
was  digested  and  absorbed  in  experiments  on  men.  Lorisch,  however,  finds  {2eit. 
/.  Physiol.  Chem.,  1908.  xlvii.  200)  that  healthy  persons  absorb  about  60  per  cent, 
of  cellulose.  In  cases  of  chronic  constipation  the  absorption  rises  to  80  per  cent., 
whilst  in  fermentative  indigestion  it  falls  to  20  per  cent.  He  thinks  that  its 
solution  must  be  brought  about  by  a  special  ferment  in  the  intestine,  and  not 
result  entirely  from  bacterial  action,  as  has  hitherto  been  supposed. 

■•  Hoppe  Seyler  (Schafer's  '  Textbook  of  Physiology,'  i.  470). 


1 68 


FOOD  AND  DIETETICS 


Cellulose,^  then,  influences  digestion  and  absorption  in  several 
ways.  It  is  not  only  almost  useless  for  purposes  of  nutrition  itself, 
but  prevents  the  access  of  the  digestive  juices  to  the  nutritive 
ingredients  which  it  encloses,  unless  it  has  been  thoroughly  broken 
up  in  the  preparation  of  the  food.  More  than  this,  being  itself  un- 
absorbed,  it  goes  to  swell  the  bulk  of  the  already  unwieldy  mass 
which  vegetable  food  forms  in  the  intestine,  and  takes  part  in  that 
stimulation  of  the  movements  of  the  bowel  which  is  an  additional 
difficulty  in  the  way  of  absorption.  It  is  for  this  reason  that  foods 
rich  in  cellulose,  such  as  brown  bread,  fruits,  and  green  vegetables, 


»  CELLULOSE  DIGESTED  IN 

EXPERIMENTS  WITH  MEN. 

Water- 

free 

Substance 

Cellulosb. 

Food  used  (Quantities  per  day  in  Grammes). 

Undi- 
ge.sted. 

in  Food. 

In  Food. 

In  Fseces. 

Grms, 

Grms. 

Grms. 

Per  cent. 

Potatoes,      1,700    grammes;     fat,     100 

grammes ;  beer,  500  c.c. ;  gluten,  200 

grammes  . . 

— 

5-6 

1-2 

220 

Potatoes,     1,700    grammes;      fat,     100 

grammes  ;  beer,  500  c.c. 

— 

4-8 

10 

21-1 

Celery,    cabbage,    carrots — total,     1,050 

grammes  . . 

139-0 

12-5 

4-7 

37'3 

Celery,   cabbage,    carrots — total,    883  "3 

grammes  . . 

117-8 

10-4 

5  5 

52-7 

Bread,  fruit,  dry  fruit,  oil — total,  1,802 

grammes  . . 

719-0 

i6-o 

9-2 

56-0 

Bread,  fruit,  dry  fruit,  oil — total,  1,764 "S 

grammes  . . 

692-5 

16-7 

6-3 

37-0 

Rice   and    barley,   salted    radish,    vege- 

tables— total,  2,150  grammes  . . 

523-8 

17-4 

4-2 

24-0 

Rice,  salted  radish,  vegetables,  etc.,  fish 

— total,  1,800  grammes 

6157 

4-6 

0-8 

17-5 

Rice,  salted  radish,  vegetables,  etc.,  meat 

— total,  1,500  grammes 

580-1 

6-0 

05 

8-6 

Wheat  and  rye  bread  (with  yeast),  i,ooo 

grammes  . . 

616-3 

4*3 

2-5 

63-1 

Wheat  and  rye  bread  (with  yeast),  900 

grammes  . . 

554-6 

3-9 

2-0 

50-1 

Wheat  and  rye  bread  (leavened),  1,000 

grammes  . . 

619-1 

4-7 

3-3 

70-0 

Wheat   and   rye   bread   (leavened),  900 

grammes  . . 

557-a 

4 '3 

1-5 

36-4 

Decorticated    (entire)    rye    bread   (with 

yeast),  1,000  grammes  .. 

647-3 

8-2 

3-7 

45-2 

Decorticated    (entire)    rye    bread    (with 

yeast),  900  grammes 

5S2-6 

7-4 

4-1 

55-9 

Decorticated  (entire)  wheat  bread  (with 

yeast),  1,000  grammes  .. 

640-8 

6-7 

37 

55-4 

Rye  bread  (with  yeast),  1,000  grammes 

623-0 

8-2 

4-9 

597 

Rye  bread  (with  yeast),  900  grammes  . . 

570-0 

7-6 

4-8 

63-9 

Wheat  bread  (with  yeast),  1,000  grammes 

640-2 

8-9 

4*2 

47-4 

Wheat  bread  (with  yeast),  900  grammes 

576-3 

8-1 

3-8 

46-6 

INFLUENCE  OF  CELLULOSE  169 

are  recognised  as  useful  in  the  diet  of  those  who  suffer  from  sluggish 
action  of  the  bowels.  Even  for  healthy  persons,  a  moderate  amount 
of  cellulose  in  the  food  is  a  useful  intestinal  stimulant.  Purely 
carnivorous  animals,  on  the  other  hand,  do  not  appear  to  require  it 
at  all,  whereas  for  the  herbivora,  owing  to  their  long  and  sluggish 
intestine,  its  presence  in  the  food  is  a  necessity  of  life. 

This  incompleteness  of  absorption,  which  is  the  characteristic  of 
most  vegetable  foods,  affects  in  different  degrees  their  different 
nutritive  constituents.  The  fats  appear  to  be  hardly  affected  by 
it.^  Cocoa-butter  is  as  well  absorbed  as  ordinary  butter,  and 
olive  oil  as  cod-liver  oil.  Starch  and  sugar  also  are  digested  and 
sucked  up  into  the  blood  almost  to  the  last  particle.  It  is  only 
when  considerable  quantities  of  green  vegetables  or  of  such  foods  as 
peas  and  beans  are  take.,  that  one  finds  any  undigested  starch 
grains  in  the  excreta  of  healthy  persons.^  It  would  appear,  in  fact, 
that  the  proteins  have  to  bear  almost  alone  the  brunt  of  the  defective 
absorption.  Why  the  proteins  of  vegetable  food  should  be  so  much 
less  completely  absorbed  than  the  other  ingredients,  it  is  somewhat 
difficult  to  say  ;  but  the  results  of  all  experimenters  are  at  one  in 
showing  that  a  relatively  larger  amount  of  nitrogen  is  excreted  by 
the  bowel  on  a  vegetable  than  on  an  animal  diet. 

In  the  table  a  number  of  such  experiments,  which  were  all  carried 
out  on  healthy  persons,  have  been  collected,  and  the  percentage  of 
protein  which  escaped  absorption  in  each  food  compared  with  that 
in  meat.  It  will  be  observed  that  all  the  vegetable  foods  exhibit  a 
much  greater  loss  of  protein  than  meat  does. 

RELATIVE  ABSORPTION  OF  PROTEIN  IN  VARIOUS  FOODS. 

Diet. 

Meat' 

Lentil  flour  (218  grammes  daily)* 
Dried  peas  (600         ,,             ..     )* 
Beans  (500  grammes)  K 
Flour  (17            ,,       )/ 
Potatoes  (3,000  grammes)'' 
Carrots  and  fat  (412  grammes,  dried)* 
Lentils  (250  grammes,  simply  soaked  and  boiled 
till  soft)» 40-0 


'  See  experiments  by  Bourot  and  Jean  and  by  Blumenfeld  iJahres-Ber.  iiber 
Thier-Chem.,  1896,  xxvi.  58,  and  1895,  p.  46),  also  Bendix  {Thaap.  Monaishe/U, 
1895,  ix.  345- 

^  See  Moeller,  Zeit.  f.  Biolog.,  1897,  p.  91. 

'  Rubner,  Zeit.  f.  Biolog.,  1879,  xv.  121,  125. 

*  Striimpell,  Deut.  Archiv.  f.  Klin.  Med.,  1876,  xvii.  108, 

*  Rubner,  Zeit  f.  Biolog.,  1S80,  xvi.  127,  128. 

*  Prausnitz,  ibid.,  1890,  xxvi.  227. 

'  Rubner,  ibid.,  1897,  x v.  147,  160.  "  Ibid.  •  Lot.  cit.  (2). 


Protein 

not  A  bsorbed. 

2*3  per  cent 

10-5 

i7'o         „ 

303         » 

32-0              H 

39 'O         „ 

XT©  FOOD  AND  DIETETICS 

In  a  number  of  prison  diets  of  an  exclusively  vegetable  nature,  b 
which  the  protein  ranged  from  io6  to  56  grammes,  or,  if  bread  were 
excluded  from  the  reckoning,  from  41  to  2  grammes  daily,  it  was 
found  1  that  on  an  average  from  25  to  47  per  cent,  escaped  ab- 
sorption. Schuster  also  observed, 2  in  Houses  of  Correction  where 
bread,  pulses,  potatoes,  and  green  vegetables  were  given,  and  only 
60  grammes  of  meat  three  times  in  the  week,  that,  of  the  104 
grammes  of  protein  supplied,  only  78  grammes  (72  per  cent.)  were 
absorbed,  but  that  in  prisons  where  116  grammes  of  meat  and  only 
three-fifths  as  much  vegetables  were  supplied,  87  per  cent,  was 
absorbed.  Some  later  observations,  however,  have  yielded  more 
favourable  results.  Thus,  in  the  case  of  a  girl  who  lived  upon  a 
diet  consisting  exclusively  of  fruit  and  nuts,  absorption  was  found  to 
be  practically  equal  to  that  which  obtains  on  a  mixed  diet,^  and  a 
study  of  two  individuals  who  lived  upon  fruits,  nuts,  and  vegetables 
gave  a  similar  result.*  It  is  true  that  there  was  a  somewhat  greater 
loss  of  nitrogen  from  the  bowel  in  these  cases  than  one  finds  on  a 
mixed  diet,  but  this  was  almost  balanced  by  a  lesser  excretion  of 
nitrogenous  constituents  in  the  urine. 

It  would  appear  that  the  mere  presence  of  a  large  amount  of 
starch  in  the  intestine  is  per  se  unfavourable  to  the  absorption  of 
protein.^  This  is  probably  to  be  attributed  to  the  fermentation  of 
part  of  the  starch,  and  the  production  of  acids  which  unduly  quicken 
the  intestinal  movements;  on  the  other  hand,  a  moderate  degree  of 
such  acid  production  ought  to  be  actually  favourable  to  the  absorp- 
tion of  protein,  by  restraining  the  growth  of  putrefactive  ge<:ms  in 
the  intestine,  which  would  speedily  break  up  the  proteins  of  the 
food  and  carry  them  past  the  stage  in  which  they  are  available  as 
foods.  Doubtless,  also,  the  effects  of  cooking  are  less  favourable  to 
the  digestion  of  protein  than  to  that  of  starch.  Under  the  influence 
of  heat  and  moisture,  the  starch  grains  swell  and  rupture  and  burst 
through  the  walls  of  cellulose  which  enclose  them,  but  under  similar 
circumstances  the  protein  in  the  vegetable  cells  is  coagulated  and 
shrinks  away  from  its  wall  of  cellulose,  so  that  the  latter  is  likely  to 
remain  unruptured.  There  are  some'  who  go  so  far  as  to  say  that 
the  large  amount  of  nitrogen  found  in  the  intestinal  excreta  on  a 
vegetable  diet  is  not  derived  from  unabsorbed  protein,  but  from  the 

^  Hofman,  'Die  Bedeutung  von  Fleischnahrung,'  Leipzig,  1880. 
^  Quoted  by  Munk,  Weyl's  '  Handbuch  der  Hygiene,'  iii.  116. 

*  U.S,  Dep't.  of  Agriculture,  Off.  of  Experiment  Stations,  Bull.  No.  107,  1901. 

*  Caspari  and  Glaesener,  Zeit.  /.  Dtat.  u.  Physik.  Iherap.,  1903.  vii.  475. 

*  Wicke  and  Weiske,  Zeit.  /.  Physiolog.  Chemie,  1895,  xxi.  42  and  1896,  xxii.  137. 

*  See  Prausnitz,  Zeit.  f.  Bwlog.,  1897,  xxxv.  287. 


ABSORPTION  OF  VEGETABLE  PROTEIN  171 

residue  of  the  digestive  juices.  On  this  view  of  the  facts  the 
vegetable  foods  must  require  a  larger  amount  of  the  digestive  juices 
for  their  solution  than  the  animal  foods  do.  Even  if  we  accept  this 
explanation  as  in  part,  at  least,  correct,  the  fact  remains  that 
relatively  more  nitrogen  is  lost  from  the  bowel  on  vegetable  than  on 
animal  food,  and  from  this,  as  we  shall  see  shortly,  various  practical 
consequences  can  be  deduced* 


3.  The  Nutritive  Value  of  Vegetable  Foods. 

There  is  reason  to  suppose  that  the  vegetable  proteins  are  not 
of  the  same  value  for  tissue-building  purposes  as  proteins  of  animal 
origin.  The  reason  is  that  the  protein  molecule  is  built  up  of  a 
number  of  fragments  composed  of  different  amido-acids.  When 
proteins  are  disintegrated  in  the  process  of  digestion,  these  frag- 
ments are  liberated,  and,  after  absorption,  are  regrouped  to  con- 
stitute the  appropriate  proteins  of  the  body  tissues.  But  the 
amido-acids  in  vegetable  proteins  are  not  present  in  the  same 
relative  proportions  as  those  found  in  animal  proteins,  and  con- 
sequently when  vegetable  protein  is  converted  into  body  protein 
there  is  apt  to  be  considerable  waste,  for  an  excess  of  the  vegetable 
protein  has  to  be  broken  up  in  order  to  provide  those  amido  bodies 
which  are  relatively  more  abundant  in  the  animal.  Thus  it  has 
been  found  by  Thomas  that  the  following  are  the  smallest  amounts  of 
different  food  proteins  required  to  protect  body  protein  from  '  loss ' :  ^ 


Meat  protein . . 
Milk  „  ., 
Rice  „  .. 
Potato   „      .. 


30  grammes. 

31  •> 
34  u 
38 


Bean  protein . . 
Bread     „ 
Maize     ., 


54  grammes. 
76 
102        ,. 


The  most  valuable  proteins  for  repair  purposes,  therefore,  are 
those  of  the  animal  class. 

On  the  other  hand,  as  far  as  fuel  value  is  concerned,  the  vegetable 
and  animal  proteins  appear  to  be  equal ;  or,  if  anything,  it  is  vegetable 
protein  which  yields  the  greater  amount  of  heat  on  combustion. 

As  regards  the  carboh)  drates  nothing  need  be  said.  Starch  and 
sugar  are  of  necessity  derived  almost  entirely  from  vegetable  sources, 
and  their  high  nutritive  value  is  beyond  dispute. 

As  regards  fat  also,  the  daily  experience  of  the  Southern  European 


*  See  Lusk, 
1914,  p.  20. 


'The  Fundamental  Basis  of  Nutrition.'     Yale  University  Press, 


172  FOOD  AND  DIETETICS 

countries  is  confirmed  by  scientific  experiments,  which  show  that 
vegetable  fats,  such  as  olive  oil  and  cocoa-butter,  are  as  valuable 
as  means  of  nourishment  as  the  fats  of  meat  or  milk.^ 

But  we  must  by  no  means  suppose,  even  if  the  chemical  con- 
stituents of  vegetable  food  were  equal  in  nutritive  value  to  the 
corresponding  constituents  of  animal  food,  that  therefore  vegetable 
food  as  a  whole  can  replace  meat,  and  vice  versa.  The  form  in  which 
the  nutritive  ingredients  are  presented  to  the  digestive  organs 
materially  affects  their  utility  as  foods.  A  glass  of  whisky  is 
chemically  the  same  whether  it  be  taken  '  neat '  or  diluted  with  a 
tumblerful  of  water,  but  the  effects  on  the  body  are  radically 
different. 

The  question,  therefore,  presents  itself:  Is  it  better  to  obtain  the 
nutritive  constituents  of  our  food  in  an  animal  or  a  vegetable  form  ? 
and  an  attempt  to  reply  to  this  question  raises  the  whole  problem  of 
vegetarianism.  With  that  problem  we  must  now  concern  ourselves 
for  a  short  space.* 

Vegetarianism  may  be  advocated  either  on  physiological  or  on 
economic  grounds. 

As  regards  the  physiological  argument,  it  may  be  pointed  out — 
what  is  apt  to  be  lost  sight  of — that  the  vegetarian  question  is  really 
a  question  of  protein,  and  of  that  alone.  The  carbohydrates  of  the 
diet  must  almost  perforce  be  derived  from  the  vegetable  kingdom, 
for  there  alone  are  they  to  be  found  in  any  quantity,  and  it  has 
already  been  pointed  out  that  the  fat  of  the  diet  may  be  obtained 
with  equal  physiological  advantage  from  either  an  animal  or  a 
vegetable  source. 

But  as  regards  proteins  it  is  different.  Even  were  a  given 
quantity  of  pure  vegetable  protein  fully  equal  in  nutritive  value 
to  a  similar  quantity  of  the  protein  of  flesh,  we  are  still  unable  to 
extract  the  vegetable  protein  in  a  state  of  purity  and  eat  it  by  itself, 
but  must  take  it  in  the  form  in  which  it  is  presented  to  us  by  Nature. 
The  real  question,  therefore,  is :  Shall  we  eat  our  protein  in  an 
animal  or  a  vegetable  form  ?  Now,  in  the  first  place,  it  will 
scarcely  be  denied  that  vegetable  foods  are  relatively  much  poorer 
in  protein  than  animal  foods  are.  Contrast  typical  examples  of 
both  kingdoms  after  the  removal  of  water,  for  that  is  the  only  fair 
method  of  comparison,  and  one  arrives  at  the  following  results : 

*  See  references  in  footnote,  p.  i6g. 

'■^  For  a  full  scientific  discussion  of  vegetarianism,  see  Ferdinand  Hueppe,  '  Der 
Moderne  Vegetarianismus  '  (Berlin,  1900)  ;  Albert  Albu,  '  Die  Vegetarische  Diat ' 
(Leipzig,  1902)  ;  and  Stachelin,  '  Untersuchungen  uber  Vegetarische  Diat,'  Zeit. 
f,  Btolugic,  1907,  xlix.  199. 


VEGETA  RIA  NISM  1 73 

100  parts  of  dried  lean  beef  contain     . .         . .  8g  parts  of  protein, 

,,       ,,  fat  beef  contain       ..         ••         ..  51       „  „ 

.,  pea  dour        27      „  „ 

,,       ,,  wheat  ..         ..         ••         ..  16      „  „ 

rice 7      „  „ 

The  comparison  shows  that  even  the  fattest  meat  is  far  richer  in 
protein  than  the  most  nitrogenous  forms  of  vegetable  food. 

Not  only  so :  what  protein  is  present  in  vegetable  food  has  its 
value  still  further  lowered  in  many  cases  by  the  defective  nature  of 
its  absorption  in  the  body.  The  truth  of  this  has  been  already 
sufficiently  demonstrated. 

It  must  be  obvious  from  all  this  that  vegetable  food,  unless  eaten 
in  large  quantities,  will  not  yield  a  sufficiency  of  protein  to  the  body. 
The  important  question  arises,  therefore  :  How  much  protein  does 
a  healthy  man  require  in  his  food  daily  ?  This  question  has  been 
discussed  in  an  earlier  chapter,  and  it  is  only  necessary  to  remind  the 
reader  that  the  amount  of  protein  which  is  required  daily  by  a 
healthy  man  doing  a  moderate  amount  of  bodily  work  has 
been  estimated  at  about  100  grammes.*  And  what  are  the 
consequences  of  living  upon  a  diet  which  contains  less  protein 
than  this  ?  To  this  question,  as  we  have  also  seen  (p.  23),  it  is  not 
easy  to  give  an  altogether  satisfactory  reply.  In  the  first  place  it 
must  be  admitted  that  such  a  large  amount  of  protein  is  by  no  means 
necessary  for  making  good  the  mere  daily  waste  of  protein  in  the 
body.  Very  much  less  will  suffice  for  that,  and  carefully-conducted 
experiments  have  shown  that  no  impairment  of  the  stock  of  protein 
in  the  body  is  incurred  even  if  the  amount  in  the  food  be  cut  down 
to  as  low  a  level  as  60  grammes  daily.  Even  if  it  be  objected 
to  such  experiments  that  this  minimum  consumption  of  protein 
has  only  been  maintained  for  very  limited  periods,  yet  it  may  be 
replied  that  the  minimum  reached  is  not  much  below  that  which 
forms  the  average  daily  consumption  per  individual  in  a  large 
number  of  healthy  races,  such,  for  example,  as  the  Japanese.^     The 

'  It  is  not  improbable  that  the  minimum  amount  of  protein  on  which  life  can 
be  healthily  maintained  varies  in  different  individuals,  and  that,  therefore,  the 
question,  How  much  protein  is  required  daily  ?  admits  of  no  categorical  reply. 
Perhaps  the  closest  approximation  to  a  solution  of  the  problem  which  the  present 
state  of  scientific  knowledge  admits  of  is  comprised  in  the  statement  that  of  the 
total  amount  of  energy  which  the  diet  contains  something  between  10  and  15  per 
cent,  should  be  supplied  in  the  form  of  protein.  Bornstein  [Zeit.  f.  Physik.  und 
Didt.  Therapie,  xvi.,  1912,  p.  24)  is  of  opinion  that  from  70  to  80  grammes  of 
protein  daily  are  sufficient  in  a  mixed  diet,  and  60  to  70  grammes  on  a  meat- 
free  diet. 

^  It  may  be  fairly  objected  to  this  statement  that  the  average  individual  in 
such  races  is  of  much  smaller  body-weight  than  the  ordinary  European. 


174  FOOD  AND  DIETETICS 

reply  of  scientific  experiment,  therefore,  as  far  as  it  can  be  applied 
to  the  problem  under  consideration,  would  be  that  it  is  undoubtedly 
possible  to  maintain  a  healthy  life  upon  such  a  daily  amount  of 
protein  as  is  contained  in  a  moderate  quantity  of  vegetable  food, 
and  the  accumulated  experience  of  vegetarian  races  fully  bears 
this  out. 

This,  however,  does  not  dispose  of  the  question.  There  is  such  a 
thing  as  degrees  of  health.  While  one  freely  admits  that  health  and 
a  large  measure  of  muscular  strength  may  be  maintained  upon  a 
minimum  daily  supply  of  protein,  yet  I  think  that  a  dispassionate 
survey  of  mankind  will  show  that  races  which  adopt  such  a  diet  are 
lacking  in  what,  for  want  of  a  better  word,  one  can  only  describe  as 
energy.  Now,  energy  is  not  to  be  confused  with  muscular  strength. 
A  grass-fed  cart-horse  is  strong ;  a  corn-fed  hunter  is  energetic. 
Energy  is  a  property  of  the  nervous  system  ;  strength,  of  the  muscles. 
Muscles  give  us  the  power  to  do  work ;  the  nervous  system  gives  us 
the  initiative  to  start  it.  Muscles  do  their  work  upon  carbohydrates, 
which  are  the  characteristic  nutritive  constituent  of  vegetable  foods  ; 
the  brain  appears  to  require  nitrogen,  which  can  only  be  obtained  in 
a  concentrated  form  from  animal  sources.  If  protein  food,  therefore, 
be  regarded  as  a  nervous  food,  a  diet  rich  in  it  will  make  for  intel- 
lectual capacity  and  bodily  energy,  and  it  is  not  without  reason  that 
the  more  energetic  races  of  the  world  have  been  meat-eaters. 

The  Scottish  peasants  are  often  adduced  as  an  example  of  a  high 
degree  of  energy  and  intellectual  capacity  produced  from  a  vegetable 
diet.  But  this  is  the  very  exception  which  proves  the  rule,  for  the 
Scottish  peasant  of  the  last  generation  was  not  only  fed  on  a  highly 
nitrogenous  form  of  vegetable  food — oatmeal — but  the  protein  of  this 
was  still  further  supplemented  by  the  addition  of  milk,  of  which 
2  to  3  Scots  pints  (each  equal  to  3^  imperial  pints)  used  to  be  allowed 
to  each  family  daily  in  the  form  of  wages. 

The  difference,  in  fact,  between  an  animal  fed  on  a  highly  nitro- 
genous diet  and  one  supplied  with  little  nitrogen  is  the  difference 
between  a  steam-engine  at  half-pressure  and  one  which  is  producing 
its  full  horse-power.  It  is  the  difference  between  a  tiger  pacing  its 
cage  and  a  cow  lying  upon  the  grass  ;  both  are  healthy,  but  the  type 
or  degree  of  health  is  very  different  in  the  two  cases. 

'  The  hunted  deer,'  says  Haughton,  '  will  outrun  the  leopard  in  a 
fair  and  open  chase,  because  the  work  supplied  to  its  muscles  by  the 
v'egetable  food  is  capable  of  being  given  out  continuously  for  a  long 


STRENGTH  VERSUS  ENERGY  175 

* 
period  of  time ;  but  in  a  sudden  rush  at  a  near  distance,  the  leopard 
will  infallibly  overtake  the  deer,  because  its  flesh  food  stores  up  in 
the  blood  a  reserve  of  force  capable  of  being  given  out  instantane- 
ously in  the  form  of  exceedingly  rapid  muscular  action,' 

Not  only,  I  think,  does  a  diet  rich  in  protein  make  for  physical 
and  mental  energy  :  it  seems  to  increase  also  one's  power  of  resisting 
disease  (see  also  p.  180). 

An  abundant  supply  of  protein  seems  to  be  necessary  if  the  blood 
and  muscles  are  to  be  kept  in  good  condition,  and  by  promoting 
oxidation  it  increases  vigour  and  diminishes  the  tendency  to  an 
undue  accumulation  of  fat.  The  nervous  system,  too,  seems  to 
require  a  plentiful  supply  of  protein  if  those  mysterious  influences 
which  emanate  from  the  brain  and  spinal  marrow  are  to  be 
maintained  with  sufficient  potency  to  enable  the  tissues  to  ward  off 
the  inroads  of  disease. 

To  growing  children  a  deficiency  of  protein  in  the  diet  is  specially 
disastrous,  for  the  lack  of  building  material  which  it  entails  may 
result  in  impaired  growth  and  development,  the  consequences  of 
which  may  last  throughout  life. 

For  the  same  reason  persons  who  habitually  live  on  a  minimum 
of  protein  are  apt  to  convalesce  but  slowly  after  an  acute  illness,  for 
once  their  tissues  are  broken  down,  they  have  no  ready  surplus  of 
building  material  out  of  which  to  repair  them. 

Everyone  knows  the  feeling  of  well-being  which  follows  a  meal 
containing  meat.  That  this  is  due  to  the  protein  in  meat,  and  not  to 
its  extractives,  is  shown  by  the  fact  that  whereas  the  addition  of  the 
extractives  of  meat  to  foods,  such  as  bread,  is  unable  to  produce 
this  feeling,  yet  such  vegetable  substances  as  oatmeal,  which  are 
rich  in  protein,  are  capable  of  exciting  it  in  a  considerable  degree. 
A  full  meal  of  nitrogenous  food  is  an  actual  stimulant  to  the  tissues 
of  the  body,  and  is  of  value  even  if  it  only  comes  at  long  intervals, 
for  its  good  effects  would  appear  to  be  not  altogether  of  a  transient 
nature.  This  stimulation  of  the  tissues  must  also  make  for  resisting 
power. 

Of  course,  there  is  another  side  to  all  this,  and  the  consumption 
of  an  excess  of  nitrogenous  food  is  not  free  from  dangers.  At 
the  present  time  there  is  no  great  likelihood  that  the  English- 
speaking  races,  at  least,  will  suffer  from  a  deficiency  of  nitrogen  in 
their  food.  The  danger,  indeed,  is  all  the  other  way,  in  the  direction 
of  a  too  liberal  consumption  of  meat.  It  is  for  insisting  upon  the 
disadvantages  of  such  a  course,  and  on  the  feasibility  of  living  upon 
a   di«t  from  which   meat   is  altogether  excluded,   that  we  in   this 


176  FOOD  AND  DIETETICS 

* 
country  owe  even  the  extremest  vegetarians  a  considerable  debt  of 
gratitude;  and  if  the  above  objections  to  living  upon  a  minimum 
of  protein  can  be  shown  to  be  groundless,  as  Chittenden  and  his 
followers  believe,  then  the  objections  to  a  purely  vegetarian  diet 
largely  disappear  also. 

Granted,  then,  that  the  consumption  of  only  a  moderate  quantity 
of  purely  vegetable  food  is  apt  to  mean  a  lack  of  protein  in  the  diet, 
with  all  its  attendant  risks,  we  have  next  to  ask.  How  may  this 
deficiency  be  supplemented  ?  The  reply  is  that  this  may  be  effected 
in  one  of  three  ways  : 

1.  The  mixed  feeder  solves  the  problem  by  adding  to  a  consider- 
able basis  of  vegetable  material  a  moderate  amount  of  food  obtained 
from  animal  sources.  Meat  and  fish  are  concentrated  forms  of 
protein  food,  and  by  their  use  he  is  able  to  supplement  the  com- 
paratively small  amount  of  nitrogen  contained  in  the  rest  of  his  diet. 

What  the  ideal  proportion  between  the  vegetable  and  animal 
constituents  of  a  mixed  diet  should  be  it  is  a  little  difficult  to  say. 
Voit  considers  that  35  per  cent,  of  the  total  protein  required  daily 
should  be  taken  in  an  animal  form.  This  would  be  represented  in 
an  ordinary  diet  by  7  ounces  of  meat  (two  moderate-sized  platefuls). 
If  the  proportion  of  animal  protein  is  habitually  three-fourths  of  the 
total,  it  is  considered  by  many  that  there  is  a  danger  of  producing 
disease,  especially  gout. 

Actual  observation  of  eighty-seven  dietaries  in  the  United  States 
showed  that,  of  the  total  food  consumed,  45  per  cent,  was  in  an 
animal,  and  55  per  cent,  in  a  vegetable,  form.  The  former  proportion 
is  probably  too  high,  and  in  all  likelihood  we  shall  not  be  far  wrong 
if  we  reckon  that  an  ordinary  diet  should  contain  one  part  of  raw 
animal  food  to  every  three  parts  of  uncooked  vegetable  material. 
This  relation  is  pretty  nearly  observed  in  the  relative  proportions  of 
meat  and  bread  in  an  ordinary  sandwich.  It  is  obvious,  however, 
that  the  exact  proportions  must  vary  somewhat  with  the  form  in 
which  the  vegetable  food  is  taken. 

2.  There  is  a  special  class  of  *  vegetarians '  who  supplement  the 
protein  of  their  diet  from  two  animal  sources  only — eggs  and  milk.^ 
That  these  are  both  well  adapted  to  supply  protein  we  have  already 
seen,  but  their  superiority  to  meat  and  fish  is  not  so  evident.  A  diet 
of  this  sort  has  been  investigated  by  Cramer. ^     It  consisted  of  whole- 

^  This  is  sometimes  called  the  '  V.  E.  M.'  diet,  from  its  consisting  of  vegetables, 
eggs  and  milk.  The  term  was  first  introduced  by  the  late  Professor  Jarrett,  ol 
Cambridge  (see  Newman's  '  Essays  on  Diet '). 

^  Zeit,  /.  Phystolog.  Ckemie,  1SS2,  vi.  346. 


METHODS  OF  SUPPLEMENTING  PROTEIN        177 


meal  bread,  potatoes  and  fruit,  with  the  addition  of  eggs  and  milk. 
The  consumer  was  a  so-called  vegetarian  of  eleven  years'  standing. 
The  diet  contained  altogether  only  74  grammes  of  protein,  of  which 
rather  more  than  one-third  was  derived  from  the  eggs  and  milk.  It 
was  therefore  deficient  in  protein  (according  to  the  ordinary  standard) 
to  start  with,  and  not  only  so,  but  fully  21  per  cent,  of  the  protein  was 
found  not  to  be  absorbed. 


BREAD. 
28i  ozs. 

2400    C   C 

1 

MILK. 
I'S  Quarts 

IJ500  CC 

PEAS. 
7  Ozs. 

6  70  CC 

EGOS. 

si  bGQS 

268CC 

2  35  Crms 

BEEr. 

Kb. 

200CC 

^__ 

„_ 

227  Crms. 

Fio.  n. — Bulk  amd  Weight  of  Different  Forms  or  Food  yikldino  thi 

Same  Quantity  of  Protein. 

A  moie  liberal  use  of  milk  might  have  remedied  the  defects  in  this 
diet,  and  it  would  then  be  open  to  no  physiological  objection,  except 
the  difficulty  (and  often  the  expense)  of  obtaining  a  sufficient  supply 
of  milk.     The  addition  of  cheese  would  also  be  an  advantage. 

There  is  no  doubt  that  this  modified  form  of  vegetarianism  has 
much  to  recommend  it,  and  it  often  agrees  better  with  gouty  persons 

13 


178  FOOD  AND  DiETETICS 

than  a  diet  into  which  meat  enters  in  any  large  amount.*  The  great 
development  in  the  manufacture  of  casein  products  in  recent  times 
has  made  the  adoption  of  such  a  diet  a  comparatively  simple  matter 
(see  also  p.  550). 

3.  To  the  consistent  vegetarian  the  only  available  method  of 
increasing  the  proportion  of  protein  in  his  diet  is  by  increasing  the 
total  amount  of  food  consumed,  and  especially  by  having  large 
recourse  to  those  vegetable  substances,  such  as  the  pulses,  which 
are  specially  rich  in  nitrogen. 

Let  us  suppose  that  dry  lentils  are  selected  as  the  protein-carrier. 
It  would  take  450  grammes  of  these  to  supply  the  total  protein 
required  daily,  and  this  quantity  must  be  further  increased  to 
500  grammes  in  order  to  allow  for  the  loss  of  10  per  cent,  of  protein 
from  defective  absorption,  and  when  cooked  into  a  thick  porridge 
the  total  weight  of  the  mass  would  be  2,000  grammes.  Now, 
this  is  a  very  formidable  figure  when  one  remembers  that  only 
600  grammes  of  cooked  meat  would  be  required  to  supply  the  same 
amount  of  protein. 

In  the  preceding  diagram  (Fig.  12)  the  bulk  and  weight  of  different 
forms  of  cooked  animal  and  vegetable  food  required  to  yield  the  same 
amount  of  protein  are  contrasted,  and  it  conclusively  demonstrates 
the  superiority  of  eggs  and  meat  as  compact  sources  of  nitrogen  even 
over  milk,  and  still  more  over  such  vegetable  foods  as  bread  and  peas. 

The  conclusion,  therefore,  seems  justified  even  on  a  priori  grounds, 
that,  if  one  attempts  to  obtain  the  usual  supply  of  protein  in  a  purely 
vegetable  form,  he  must  be  prepared  to  consume  a  rather  bulky 
diet.  Actual  observation  confirms  this.  Even  the  above-mentioned 
'  veg'etarian '  consumed  about  2,960  grammes  (about  6^  pounds)  of 
cooked  food  daily.  If  he  had  replaced  the  eggs  and  milk  in  his  diet 
by  vegetable  foods,  the  total  quantity  would  have  risen  to  nearly 
3,500  grammes.  Seeing  that  the  total  capacity  of  an  ordinary 
stomach  is  only  about  1,200  grammes^  (2|  pounds),  this  means  that 
the  stomach  must  be  filled  to  the  limit  of  its  capacity  thrice  in  the 
day.  And  yet  even  then  we  saw  that  only  74  grammes  of  protein 
would  be  ingested. 

The  causes  of  this  inevitable  bulkiness  of  a  purely  vegetable  diet 
have  already  been  dwelt  upon  and  have  been  shown  to  depend  on 
the  wateriness  of  vegetable  food,  especially  when  cooked,  and  on 
the   large   amount   of  indigestible   cellulose  which   it  contains,  to 

1  See  Haig's  '  Diet  and  Food,'  London,  1898. 

•  See  Hofman,  '  Die  Bedeutung  \on  Fleischnahrung.' 


BULK  IN  ESS  OF  VEGETABLE  DIET  179 

which  may  be  added  that  the  small  amount  of  protein  present  is 
diluted,  as  it  were,  by  a  disproportionate  quantity  of  starch.  Hence, 
in  order  to  get  a  sufficiency  of  protein  in  a  purely  vegetable  diet,  one 
is  obliged  to  consume  much  more  starch  than  is  really  required. 
The  physiological  effects  of  this  excessive  bulk  now  call  for  some 
consideration. 

One  of  the  first  results  of  the  habitual  ingestion  of  a  bulky  diet  is 
that  the  stomach  and  bowels  become  somewhat  distended.  Examples 
of  this  are  found  in  the  disproportionate  abdominal  development  of 
cattle  and  other  herbivora,  and  in  the  so-called  '  potato- belly  '  of  the 
Irish  peasant.  This  distension  has  the  effect  of  increasing  the 
capacity  of  the  stomach  so  that  more  food  can  be  taken.  Indeed, 
until  this  increase  in  capacity  has  taken  place  there  is  difficulty 
in  consuming  a  sufficiency  of  purely  vegetable  food  to  meet  the 
demands  of  the  body.  For  this  reason  the  adoption  of  a  vegetable 
diet  is  useful  in  some  forms  of  obesity,  especially  when  complicated 
by  habitual  constipation.  The  treatment  involves  a  species  of  fraud 
upon  the  body,  the  distension  of  the  stomach  producing  a  feeling  of 
satiety  before  a  sufficiency  of  nutriment  has  really  been  taken  in. 
Unfortunately,  the  increase  in  capacity  of  the  abdominal  organs,  by 
which  the  greater  bulk  of  a  vegetable  diet  is  compensated  for,  does 
not  seen  to  be  accompanied  by  an  increased  power  of  digestion  and 
absorption.  Observations  made  upon  vegetarians  of  several  years' 
standing  by  Voit^  and  by  Cramer  2  showed  that  the  amount  of  food 
which  escaped  digestion  in  these  subjects  was  quite  as  great  as  one 
finds  it  to  be  in  those  who  have  but  recently  adopted  that  form  of 
diet.  Indeed,  one  of  the  results  most  commonly  observed  to  follow 
the  habitual  use  of  purely  vegetable  food  is  an  enfeeblement  of  the 
digestive  organs  and  a  tendency  to  chronic  diarrhoea.  The  reason 
for  this  is,  perhaps,  that  the  very  bulkiness  of  vegetable  food,  and 
its  tendency  to  undergo  acid  fermentation,  causes  it  to  be  hurried 
through  the  small  intestine  into  the  larger  bowel,  where  absorption 
is  much  less  active.  Thus,  one  finds  that  whereas  the  average 
amount  of  material  evacuated  daily  from  the  large  bowel  on  an 
animal  diet  amounts  to  120  grammes,  it  reaches  333  grammes  in 
the  case  of  a  purely  vegetable  feeder.^ 

The  very  necessity  for   the   manipulation  by  the  stomach  and 

bowels  of  such  a  large  mass  of  material  constitutes  another  of  the 

disadvantages  of  a  purely  vegetable  diet.     For  such  manipulation 

»  Voit,  Zeit.f.  Biolog.,  1889,  xxv.  232. 

'  Cramer,  Zeit.  f.  Physiolog.  Chemie,  1SS2,  vi.  346. 

•  Voit,  Zeit.f.  Biolog.,  1889,  xxv.  232. 


«8o  FOOD  AND  DIETETICS 

involves  greater  muscular  effort  on  the  part  of  the  stomach  and 
intestinal  walls,  and  that  implies  a  large  expenditure  of  blood  and 
of  nervous  energy.  There  is  thus  less  of  these  left  for  other  purposes, 
and  especially  for  the  use  of  the  brain,  hence  the  feeling  of  lassitude 
always  experienced  after  a  heavy  meal.  This  prostitution  of  nervous 
energy,  from  higher  purposes  to  the  mere  manipulation  of  food  which 
vegetarianism  involves,  is  another  reason  for  regarding  that  mode  of 
life  as  a  retrogression  in  civiUzation.  The  more  concentrated  (within 
reasonable  limits)  we  can  manage  to  make  our  food,  the  more  easily 
is  it  appropriated  by  the  body,  and  the  greater  is  the  amount  of 
energy  which  we  have  to  spare  for  our  intellectual  and  other  needs. 

It  must  be  added,  lastly,  that  the  wateriness,  which  is  such  a 
pronounced  characteristic  of  vegetable  food,  is  itself  a  disadvantage. 
Observation  even  shows^  that  it  does  not,  as  is  often  maintained, 
diminish  the  amount  of  water  which  is  drunk.  On  the  other  hand, 
the  fluid  in  the  food  is  absorbed  into  the  blood  and  retained  in  the 
body,  rendering  its  fluids  more  dilute  and  its  tissues  more  watery. 
It  is  probable  that  this  accounts  for  the  '  soft '  condition  and 
flabbiness  of  those  who  habitually  consume  large  quantities  of  the 
more  watery  forms  of  vegetable  food.  It  is  doubtless  also  an 
important  factor  in  producing  the  low  resisting  power  which  is 
characteristic  of  such  persons.  That  this  low  resistance  to  disease, 
to  which  reference  has  so  often  been  made,  is  no  mere  bogey  of  the 
scientific  imagination  is  shown  by  the  history  of  the  epidemics 
which  from  time  to  time  break  out  amongst  those  who  are  com- 
pulsorily  maintained  on  an  entirely  vegetable  diet. 

In  concluding  this  subject,  it  should  be  pointed  out  that  the  dis- 
advantages of  a  purely  vegetable  diet  aflfect  the  outdoor  laoourer 
much  less  than  one  engaged  in  more  sedentary  pursuits.  The 
labourer  actually  requires  a  large  amount  of  carbohydrate  to  enable 
him  to  perform  his  muscular  work,  and  in  eating  large  quantities  of 
vegetable  food  for  this  purpose  he  is  almost  sure  to  get  as  much 
protein  as  he  requires  also.  The  free  action  of  the  skin,  too,  which 
his  work  insures  carries  off  from  the  body  the  excess  of  water  which 
his  diet  contains,  whilst  his  active  work  in  the  open  air  induces  an 
appetite  for  large  meals. 

With  the  sedentary  worker,  however,  the  case  is  different.  He 
requires  much  less  carbohydrate  than  the  labourer,  while  his  demand 
for  protein  still  remains  considerable  ;  and  in  endeavouring  to  obtain 
from  purely  vegetable  sources  a  sufficiency  of  the  latter  ingredient 

»  See  Meyer,  Zeit.  f.  Biolog.,  1871,  vii.  i,  and  Rutgers,  ibid.,  1888,  xxiv.  351. 


DISADVANTAGES  OF  VEGETARIANISM  i8i 

he  inevitably  overburdens  his  diet  with  an  excess  of  the  former, 
which  his  comparatively  feeble  digestion  is  unable  to  master,  while 
he  has  no  ready  means  of  getting  rid  of  the  surplus  water  which  it 
contains.  For  this  reason  the  sedentary  man  is  much  less  likely  to 
be  a  successful  example  of  vegetarianism  than  one  who  leads  a  more 
active  life."'   General  experience,  I  think,  bears  this  out. 

4.  Relative  Economy  of  Vegetable  Food. 

When  the  relative  cost  of  animal  and  vegetable  food  comes  to  be 
considered,  the  advocate  of  vegetarianism  is  on  much  firmer  ground. 
There  can  be  no  doubt  that  vegetable  food  is  much  the  cheapest. 
This  is  shown  in  the  diagram  to  which  attention  has  already  been 
directed  (Plate  III.),  and  which  exhibits  the  number  of  Calories 
obtained  from  a  shilling's  worth  of  diflferent  forms  of  food.  One  sees 
that  a  given  sum  yields  a  far  larger  amount  of  fuel  for  the  body  when 
spent  on  bread,  peas,  or  potatoes,  than  when  invested  in  eggs,  fish,  or 
beef,  or  even  in  such  comparatively  cheap  animal  foods  as  cheese 
and  milk. 

This  superiority  of  vegetable  food  appUes  not  merely  to  the  carbo- 
hydrates and  fats,  which  are  its  fuel  constituents,  but  to  proteins  as 
well.  The  following  table  shows  the  cost  of  1  pound  of  protein 
when  purchased  in  different  forms  : 


X  pound  protein  in  peas  costs     . . 

7d. 

„            „          oatmeal  costs 

7i^ 

„             „          bread          ,, 

..     IS.  6d. 

»       _    „          milk 

..       2S.   2d. 

beef 

..     2s.  8d. 

On  an  average,  therefore,  one  will  get  about  four  times  as  much 
vegetable  as  animal  protein  for  a  given  sum. 

A  consideration  of  the  respective  methods  by  which  plants  and 
animals  derive  the  raw  material  for  building  up  their  tissues  will 
prove  that  the  former  must  necessarily  be  cheaper  sources  of  food- 
supply  than  the  latter. 

The  atmosphere  and  the  soil  are  the  primary  sources  of  all  food. 
The  former  contains  carbon  in  the  form  of  carbonic  acid  gas  along 
with  water  vapour.  The  latter  contains  water  and  nitrogen  in  the 
form  of  nitrates.  Now,  animals  are  unable  to  make  use  of  carbon 
and  nitrogen  in  these  simple  forms,  but  plants  can.  The  plant, 
aided  by  the  light  and  heat  of  the  sun,  and  by  water,  builds  up  the 
carbon  of  the  carbonic   acid  gas   into  carbohydrates.      These  are 

1  The  defective  appetite  of  many  town-dwellers  is  a  great  obstacle  to  their 
successful  adoption  of  vegetarianism.  The  fact  that  meat  adds  to  the  '  tastiness ' 
of  the  diet  is  one  of  its  great  advantages  as  a  food,  and  it  is  for  this  reason  that  it 
is  unconsciously  sought  after.  (See  also  Rubner,  '  Volksernahrungs  Fragen,' 
p.  86,  ct  itq.) 


l82 


FOOD  AND  DIETETICS 


eaten  by  animals,  and  broken  up  by  them  into  carbonic  acid  gas  and 
water,  and  returned  through  the  lungs  in  that  form  to  the  atmosphere 
once  again  (see  Fig.  13).  The  plant  also  lays  hold  of  the  nitrates  in 
the  soil,  and  works  up  the  nitrogen  which  they  contain  along  with  some 


BlPIRED 


-ATMOSP*** 
Fig.  13. — Carbon  Food  Cycle. 

of  the  carbon  derived  from  the  atmosphere  into  complex  vegetable 
proteins  (Fig.  14).     These  also  are  consumed  by  animals,  and  after 


'"-  t  ROO 


Fig    14. — Nitrogen  Food  Cvclb. 

a  brief  life  as  the  proteins  of  muscle  and  other  tissues,  are  eliminated 
through  the  kidneys  in  the  form  of  urea.  By  the  action  of  bacteria, 
the  urea  is  further  broken  up  into  compounds  of  ammonia,  and  these 


NATURAL  FOOD  CYCLE  183 

in  their  turn  are  taken  in  hand  by  another  set  of  bacteria,  and  the 
nitrogen  which  they  contain  converted  into  nitrates  once  more. 

Not  all  of  the  nitrogen,  however,  is  so  fortunate.  Part  of  it  is 
split  off,  and  goes  to  join  the  immense  mass  of  free  nitrogen  contained 
in  the  atmosphere.  There  is,  then,  a  certain  loss  of  nitrates  from  the 
soil  when  the  latter  produces  vegetables  which  are  used  for  animal 
food.  The  loss  would  be  greater  than  it  actually  is  were  it  not 
for  the  existence  of  another  kind  of  bacteria,  whose  acquaintance 
scientific  men  have  but  recently  made.  These  establish  themselves 
upon  the  roots  of  certain  plants,  especially  the  pulses,  and  perform 
the  kindly  office  of  laying  hold  of  some  of  the  free  nitrogen  in  the  air 
and  fettering  it  in  the  form  of  nitrates.  Thus  they  enrich  the  soil 
and  feed  the  plant  on  whose  roots  they  live.  In  this  way  the  nitrogen 
food-cycle  of  the  world  is  completed.^ 

It  is  owing  to  this  constant  loss  on  the  part  of  the  soil  that  farmers 
are  in  the  habit  of  using  nitrates  as  a  manure  for  fields  from  which 
heavy  crops  of  cereals  are  continually  being  taken.  In  an  address 
by  Professor  Crookes  before  the  British  Association  a  few  years  ago 
he  pointed  out  that  the  available  supply  of  nitrates  is  running  short, 
and  predicted  that  dire  results  would  follow  upon  its  complete 
exhaustion. 

One  may  now  naturally  ask  :  Would  it  not  be  possible  for  science 
to  step  in,  and  itself  work  up  the  primitive  forms  of  food  into  those 
complex  forms  which  animals  require,  without  the  aid  of  plants  ? 
In  the  case  of  carbohydrates  this  has  already  been  achieved,  for 
sugar  can  be  built  up  out  of  its  elements  by  the  chemist  as  well  as 
by  the  plant.  It  is  in  the  case  of  the  proteins,  however,  which  are 
such  expensive  forms  of  food,  that  an  artificial  method  is  most  to  be 
desired.  But  even  with  respect  to  them  recent  research  is  stated  to 
have  been  crowned  with  success,  and  a  form  of  protein  produced 
which  is  identical  with  the  same  article  as  manufactured  by  Nature. 
It  is  not  likely,  however,  that  these  chemical  processes  can  be  carried 
out  on  a  commercial  scale.  Certainly  not  for  a  very  long  time  to 
come.  And  yet,  were  it  possible  to  fix  directly  the  free  nitrogen 
which  is  waiting  in  unlimited  quantity  in  the  atmosphere,  the  problem 
would  be  half-way  to  solution.  In  his  address  Professor  Crookes 
indicated  a  method  which  gives  reason  to  hope  that  this  may  yet  be 
done,  and  the  nitrogen  of  the  air  be  converted  into  nitrates  in  the 

'  The  reader  will  find  a  much  fuller  account  of  Nature's  chemical  food-cycle, 
and  the  part  played  in  it  by  bacteria,  in  '  The  Story  of  Germ  Life,'  by  H.  W. 
Conn  (London  :  George  Newnes,  Lim.),  chap.  iv. 


i84  FOOD  AND  DIETETICS 

same  way  as  by  the  action  of  root  bacteria.  Though  such  compounds 
are  of  no  direct  use  as  food  to  man,  yet  they  could  be  used  to  pre- 
pare the  soil  for  abundant  crops  of  grain.  Notwithstanding  all  these 
scientific  conquests,  accomplished  or  imminent,  those  who  do  not 
look  forward  to  the  day  when  foods  will  be  swallowed  in  the  form  of 
compressed  tablets  need  not  be  filled  with  despair.  It  by  no  means 
follows  because  an  artificial  product  is  identical  with  a  natural  one  in 
composition  that  therefore  it  can  replace  the  latter  as  food.  The 
analyst  may  pronounce  two  compounds  the  same,  but  the  living  body 
can  often  detect  subtle  differences  which  may  lead  it  to  make  use  of 
the  one  and  reject  the  other.  That,  at  least,  has  been  the  experience 
with  such  scientific  preparations  as  •  artificial  milk.' 

The  differences  in  the  mode  of  feeding  of  animals  and  plants 
respectively,  which  have  been  above  described,  are  well  summed  up 
in  the  saying  of  an  eminent  French  physiologist,  that  in  the  main 
animals  are  analytical,  and  plants  are  synthetical,  feeders.  And  seeing 
that  this  is  the  case,  seeing  that  animals  must  have  complex  com- 
pounds as  their  nutriment,  and  that  these  can  only  be  derived  either 
from  vegetables  or  from  the  flesh  of  other  animals,  it  follows  that 
the  former  must  be  a  much  cheaper  source  of  supply  than  the  latter. 
The  difference  is  exactly  the  same  as  between  dealing  with  a 
manufacturer  direct  and  through  the  medium  of  a  middle-man.  In 
converting  vegetable  compounds  into  flesh  an  animal  takes  toll  of 
them.  It  has  its  commission,  which  must  be  paid  by  the  individual 
who  consumes  the  flesh  and  by  the  community.  That  the  com- 
mission amounts  to  a  considerable  percentage  of  the  original  vegetable 
food  is  not  open  to  dispute.  '  It  is  not  extravagant  to  say,'  writes 
one  author,  '  that  every  acre  well  cultivated  would  feed  seven  times 
as  many  men  by  its  crops  as  could  be  fed  on  the  flesh  of  cattle  who 
do  but  graze  on  its  spontaneous  grasses  ;'^  and  the  same  writer  asserts 
that  it  has  been  found  in  a  vast  pig  butchery  at  Cincinnati  that  the 
oatmeal  used  in  fattening  the  pigs  would  have  gone  nearly  four  times 
as  far  as  the  pork  produced  went  in  feeding  mankind. ^  Another 
investigator  has  calculated  that  2^  acres  devoted  to  the  production 
of  mutton  will  support  one  man  a  year,  whilst  the  wheat  grown  on 
the  same  area  would  support  sixteen  men.^  Without  committing 
ourselves  to  the  literal  correctness  of  such  calculations,  we  may  yet 
believe  that  they  are  a  close  approximation  to  the  truth,  and  the 
economic  questions  which  they  suggest  are  of  far-reaching  national 

1  Newman.  'Essays  on  Diet,'  p.  4.  '  Ibid.,  p.  5. 

*  Hunter,  '  Dietetic  Reformer.' 


CHEAPNESS  OF  VEGETABLE  FOODS  185 

importance.  But  however  this  may  be  from  the  point  of  view  of  a 
nation  as  a  whole,  individuals  in  civilized  countries  are  always  found 
to  be  willing,  when  they  are  able,  to  pay  for  animal  food  the  high 
price  demanded  for  it,  by  reason  of  the  imperious  necessity  of 
obtaining  a  concentrated  form  of  nitrogenous  food.  From  the 
individual  point  of  view,  too,  it  must  be  remembered  that  there  is 
an  offset  to  the  comparative  cheapness  of  vegetable  food  in  the  larger 
amount  of  cooking  which  such  a  diet  entails.  One  scientific  writer,^ 
who  inquired  into  this  point  in  his  own  case,  found  that  a  mixed 
diet  cost  him  2s.  y^d.  per  diem,  while  a  purely  vegetable  diet  cost 
2s.  3d. ;  but  the  former  required  only  eighteen  and  a  half  hours' 
cooking  in  the  week,  the  latter  sixty-three  hours.  Assuming  that  the 
fuel  cost  ^d.  per  hour,  this  would  mean  that  the  cost  of  the  mixed 
diet,  plus  cooking,  was  igs.  i^d.  per  week,  as  compared  with  i8s.  4d. 
for  the  vegetable  diet — a  difference  which  is  very  slight.  If  these 
figures  be  at  all  correct,  it  is  not  true  to  say,  as  some  have  done, 
that  the  abandonment  of  meat  is  equivalent  for  a  working  man  to 
a  rise  of  5s.  a  week  in  his  wages. 

In  conclusion  it  may  be  well  to  summarize  the  main  points  in  the 
argument  which  has  been  pursued  in  this  chapter : 

1.  Vegetable  foods  are  rich  in  carbohydrates,  and,  with  a  few 
exceptions,  comparatively  poor  in  protein  and  fat.  They  are  also 
bulky,  partly  from  their  richness  in  starch,  but  also  from  the  presence 
of  cellulose  and  a  large  amount  of  water.  Even  if  compact  in  their 
raw  state,  they  tend  to  take  up  much  water  and  to  become  bulky  on 
cooking. 

2.  Animal  foods  are  rich  in  protein  and  fat,  but,  with  the  exception 
of  milk,  poor  in  carbohydrates.  They  are  compact  in  form  (again 
with  the  exception  of  milk),  and  tend  to  become  more  so  on  cooking. 

3.  Vegetable  foods  are  less  digestible  in  the  stomach,  and  on  the 
whole  less  completely  absorbed  than  animal  foods,  partly  by  reason 
of  their  bulk,  partly  because  of  the  indigestible  coating  of  cellulose 
which  invests  their  nutritive  constituents,  and  in  part  also  from  their 
tendency  to  undergo  fermentation  in  the  intestine,  with  the  produc- 
tion of  acids  which  hasten  on  peristalsis.  Their  protein  constituents 
suffer  more  from  defective  absorption  than  any  other  ingredient. 

4.  Both  from  chemical  composition  and  from  defective  absorption 
a  purely  vegetable  diet  is  apt  to  be  deficient  in  protein,  and  the 
question  of  vegetarianism  becomes  a  question  of  whether  it  is 
advisable  to  live  upon  a  protein-minimum  or  not. 

»  Rutgers,  Zeit. /.  Biolog.,  18S8.  xxiv.  351. 


1 86  FOOD  AND  DIETETICS 

5.  The  consistent  vegetarian  must  either  live  upon  a  diet  which  is 
relatively  poor  in  protein  or  else  consume  an  excessive  bulk  of  food. 

6.  The  adoption  of  the  former  of  these  courses,  there  is  reason  to 
believe,  tends  to  diminish  energy  and  the  power  of  resisting  disease ; 
the  latter  is  apt  to  lead  to  derangement  of  the  stomach  and  bowels. 

7.  Both  of  these  results  may  be  avoided  by  supplementing  the 
vegetable  part  df  the  diet  by  animal  substances  rich  in  protein,  but 
two-thirds  of  the  total  protein  can  safely  be  taken  in  the  vegetable 
form. 

8.  Either  meat,  fish,  eggs,  milk  or  cheese  may  be  used  as  the 
protein-carrier,  but  for  healthy  persons  the  moderate  use  of  the  first 
two  has  certain  advantages.  For  the  gouty,  perhaps  milk  and  cheese 
are  more  to  be  recommended,  while  skim  or  butter  milk,  salt  fish, 
and  the  cheaper  kinds  of  cheese  are  undoubtedly  the  most  economical. 

9.  Vegetable  foods  have  certainly  the  advantage  of  being  cheaper, 
both  as  sources  of  building  material  and  energy,  than  the  animal 
foods  are,  and  vegetarianism  may  therefore  be  recommended  on 
grounds  of  economy,  both  national  and  individual.  The  reasons  for 
the  inevitable  costliness  of  foods  of  animal  origin  have  been  pointed 
out ;  the  cost  of  cooking,  however,  must  not  be  lost  sight  of  in  this 
connection,  and  modifies  somewhat  the  above  considerations. 

10.  It  may  finally  be  added,  though  these  points  were  not  dwelt 
upon,  that  vegetable  foods  are  less  highly  flavoured  than  some 
animal  foods,  such  as  meat,  but  have  the  advantage  of  not  being 
liable  to  undergo  putrefaction,  and  of  rarely  producing  disease. 

The  therapeutic  uses  of  a  vegetable  diet  will  be  described  in  anothei 
chapter  (p.  550). 


ti87l 


CHAPTER  XI 

THE  CEREALS  :  WHEAT— BREAD 

In  the  present  chapter  we  begin  the  study  of  the  vegetable  foods  in 
detail.  In  classifying  these,  it  is  better  to  be  guided  by  practical 
convenience  rather  than  by  strict  botanical  considerations,  and  we 
may  accordingly  group  them  under  the  following  heads  : 

1.  The  cereals,  e.g.,  wheat,  oats,  maize. 

2.  The  pulses,  e.g.,  peas,  beans,  lentils. 

3.  The  roots  and  tubers,  e.g.,  carrots,  turnips,  potatoes. 

4.  Green  vegetables,  e.g.,  the  cabbage. 

5.  Fruits  and  nuts,  e.g.,  the  apple  and  walnut. 

6.  Fungi  and  algae,  e.g.,  mushrooms  and  Irish  and  Iceland  moss. 
In  a  separate  chapter  we  shall  devote  some  special  attention  to 

the  different  forms  in  which  sugar  and  spices  enter  into  the  diet. 

The  Cereals. 

From  the  botanist's  point  of  view,  the  cereals  belong  to  the  tribe 
of  grasses.  The  ©nly  part  of  them  made  use  of  as  human  food  is 
the  fruit  or  seed.  In  all  grasses  there  is  laid  up  in  the  seed  a  store- 
house of  nourishment  for  the  young  plant  during  the  early  days  of 
its  career.  It  is  interesting  to  note  that  the  effect  of  cultivation  is 
to  encourage  the  '  foresight '  of  the  parent  plant  in  providing  for  its 
young,  so  that  in  the  cultivated  grasses  {i.e.,  the  cereals)  this  store- 
house becomes  very  considerable,  and  by  robbing  the  young  plant  of 
it  we  tap  an  abundant  source  of  food-supply.  In  all  of  them  the 
different  nutritive  ingredients — proteins,  carbohydrates,  fat,  and 
mineral  matter — are  represented,  along  with  a  certain  proportion  of 
water,  which,  however,  in  the  ripe  state  does  not  amount  to  more 
than  10  to  12  per  cent,  of  the  whole  grain. 

The  proteins  vary  considerably  in  kind  in  the  different  cereals,  and 
their  value  as  tissue-formers  varies  also  (see  p.  171).    They  average, 


i88  FOOD  AND  DIETETICS 

like  the  water,  about  lo  to  12  per  cent.  In  addition  to  the  proteins, 
small  quantities  of  other  nitrogenous  substances  {e.g.,  amides)  are 
present,  the  amount  of  which  varies  in  different  cereals.  They  are 
always  more  abundant  in  the  growing  plant  than  in  the  mature 
condition. 

The  chief  carbohydrate  present  is  starch.  This  makes  up  from 
65  to  70  per  cent,  of  the  entire  grain.  Small  quantities  of  sugar  are 
also  met  with,  but  cellulose  is  not  abundant  except  in  the  outer 
protective  covering.  This  fact  is  of  considerable  advantage  as  far 
as  the  digestibility  of  the  cereals  is  concerned. 

The  proportion  of  fat  varies  very  notably  in  different  members  of 
the  group.  It  is  interesting  to  note  that  it  tends  to  be  most 
abundant  in  those  cereals  which  grow  in  northerly  latitudes,  e.g., 
oats,  whereas  in  the  cereals  of  tropical  growth,  e.g.,  rice,  it  is  almost 
absent.  In  this  the  cereals  seem  to  follow  a  general  law,  for  just  as 
the  young  whale  is  provided  by  Nature  with  a  milk  specially  rich  in 
fat,  so  the  young  cereal  which  has  to  grow  up  in  a  cold  atmosphere 
is  supplied  with  an  abundant  store  of  oil. 

The  mineral  matter  amounts  to  about  2  per  cent,  of  the  grain, 
lime  and  phosphoric  acid  being  most  abundantly  represented,  while 
the  organic  salts  are  almost  absent.  In  this  respect  the  cereals 
resemble  the  animal  rather  than  the  vegetable  foods. 

Summing  up  this  rapid  review,  the  general  composition  of  the 
cereals  may  be  said  to  be  something  as  follows : 

Water  ..         10    to  12  per  cent. 

Proteins         ..  ..  ..         ..     10     ,,  12         „ 

Carbohydrates  ..  ..         ••     65     ,,  75         „ 

Fat i  „     8         „ 

Mineral  matter         2        ., 


COMPOSITION  OF  CEREALS.' 


Wheat         

Oats  

,,     (hulled) 
Barley 

Rye 

Maize 

Rice      (in      the      husk  = 

*  paddy  ') 
Rice  (husk  removed) 

,,      (polished) 

Millet  

Buckwheat . . 


Water. 

Protein. 

Fat. 

Carbo- 
hydrates. 

Cellu- 
lose. 

120 

ii-o 

17 

71-2 

22 

100 

109 

45 

59- 1 

12  0 

6-9 

13  0 

81 

68  6 

I'3 

123 

lOI 

19 

695 

3-8 

no 

10  2 

23 

723 

21 

12-5 

97 

54 

689 

20 

105 

6-8 

1-6 

68-1 

90 

12  0 

72 

20 

768 

10 

124 

6-9 

04 

79-4 

04 

12-3 

10-4 

39 

683 

29 

130 

102 

22 

6i-3 

ii-i 

Mineral 
Matter. 

1-9 

35 
21 

«4 
21 

1-5 

40 
10 
05 
22 
22 


1  The  table  represents  the  composition  of  the  cereals  in  their  crude  form.     The 
figures  are  compiled  from  a  vast  number  of  analyses,  the  data  contained  in  the 


GENERAL  COMPOSITION  OF  CEREALS 


i8g 


COMPOSITION  OF  PRODUCTS  DERIVED  FROM  CEREALS. 


Water. 

Protein. 

Fat. 

Carbo- 
hydrates. 

Cellulose. 

Mineral 
Matter.  ' 

Wheat  meal 

I2-I 

129 

19 

70-3 

16 

12 

Fine  wheat  flour 

130 

95 

08 

753 

07 

07 

Oatmeal  . .          ..          .. 

7-2 

14-2 

7-3 

659 

35 

1-9 

Rolled  oats 

72 

154 

72 

64-8 

35 

19 

Barley  meal 

ii-g 

100 

2  2 

715 

1-8 

26 

Pearl  barley 

127 

74 

12 

767 

08 

12 

Coarse  rye  flour 

ir-4 

153 

21 

667 

23 

22 

Finest 

II-2 

67 

09 

800 

0-8 

04 

Corn  meal 

II-4 

8-5 

4-6 

72-8 

14 

13 

(fine) 

125 

6-8 

13 

78  0 

08 

0-6 

Buckwheat  flour 

140 

71 

12 

759 

06 

12 

Rizine  (flaked  rice) 

117 

79 

0-5 

795 

04 

The  exact  proportion  of  these  constituents  contained  in  each 
cereal  is  represented  in  the  tables,  and  in  order  of  their  relative 
richness  in  each  the  members  of  the  group  may  be  arranged  thus : 


Oats. 

Wheat. 

Millet. 
Buckwheat. 
Rye. 
Barley. 

Maize. 

Rice. 


Fat. 


Oats. 

Maize. 

Millet. 

Buckwheat. 
Rye. 

Wheat. 

Barley. 


Carbohydrates. 

Mineral  Matter. 

Rice. 

Barley. 

Rye. 

Wheat. 

Millet. 
Buckwheat. 

Barley. 
Maize. 
Millet. 

Oats. 
Rye. 

Wheat. 

Buckwheat. 

Maize. 

Oats. 

Rice. 

The  great  preponderance  of  carbohydrates  in  all  cereals  indicates 
that  they  should  not  be  eaten  alone,  but  along  with  other  foods 
richer  in  fat  and  protein.  This  we  have  instinctively  learned  to  do, 
and  accordingly  we  make  puddings  with  eggs  and  milk,  and  eat 
bread  with  cheese  or  spread  it  with  butter.  All  cereals  are  rather 
deficient  in  building  material,  except,  perhaps,  oats,  and  none  of 
them  can  be  regarded  as  an  important  source  of  fat.  As  a  group 
they  are  extremely  well  absorbed,  ranking  in  that  respect  next  to, 


report  on  the  composition  of  the  cereals  exhibited  at  the  Columbian  Exposition 
being  freely  used  (United  States  Bulletin  45).  The  protein  has  been  calculated 
from  the  nitrogen,  using  the  factor  57  for  all  except  barley,  maize  and  buckwheat, 
where  the  factor  6  was  employed. 


igo 


FOOD  AND  DIETETICS 


and  in  some  cases  even  above,  the  animal  foods,  and  this  fact,  com- 
bined with  their  compactness  and  richness  in  nutrients,  places  them 
in  the  front  rank  of  human  foods. 


-BRAM. 


-ENDOSPERM 


Wheat. 

In  this  country  wheat  is  by  far  the  most  important  of  cereal 
foods.  We  are  said  to  consume  6  bushels  of  it  per  head  of  the 
population  every  year.  A  food  which  is  so  largely  used  merits  a 
detailed  study. 

If  a  grain  of  wheat  be  cut  into  thin  sfices  and  examined  under  a 
microscope,  it  will  be  found  to  consist 
of  the  following  parts  (Fig.  15) : 

1.  The  germ,  or  embryo.  This  is 
simply  the  young  plant.  It  repre- 
sents about  i^  per  cent,  of  the  whole 
grain. 

2.  The  kernel,  or  endosperm.  This 
consists  of  two  large  masses  of  nutri- 
tive material  for  the  use  of  the  em- 
bryo. It  makes  up  85  per  cent,  of 
the  grain. 

3.  The  bran — an  outer  envelope 
mainly  composed  of  cellulose  im- 
pregnated with  mineral  matter,  and 
designed  as  a  protective  covering  to 
the  grain,  of  which  it  makes  up  about 
13^  per  cent. 

The  chemical  composition  of  the 
whole  grain  and  of  its  three  com- 
ponents is  shown  in  the  following 
table,  constructed  chiefly  from  ana- 
lyses by  Professor  Church.  It  will  be  noticed  that  the  germ  is 
characterized  by  its  richness  in  protein  and  fat,  the  endosperm  by 
an  abundance  of  starch,  and  the  bran  by  a  preponderance  of  mineral 
matter  and  cellulose.  It  should  be  added  that  the  germ  is  further 
peculiar  in  that  both  its  protein  and  its  carbohydrates  are  chiefly 
present  in  a  soluble  form. 


-GERM. 


Fig.    15. — Lo.NGiTUDiNAL    Section 

THROUGH      A      GrAIN      OF      WhEAT 

(Low  Power  View). 


STRUCTURE  OF  A   WHEAT-GRAIN 


191 


COMPOSITION  OF  THE  DIFFERENT  PARTS  OF  A  WHEAT  GRAIN.' 


Bran 

(n-s 

per  cent.)- 

Endosperm 
(8s  per  cent.). 

Germ 
(1-5  per  cent.). 

Whole  Grain 

(1000 

per  Cent.). 

Water         

Nitrogenous  matter        ,. 

Fat 

Starch  and  sugar            , . 

Cellulose 

Mineral  matter     . .         . . 

125 
16-4 

35 
43  6 
180 

60 

130 

10-5 
08 

743 
07 
07 

125 

357- 
13  I 

3i'2* 
18 

57 

145 

II  0 

1-2 

690 

2-6 

17 

If  the  section  of  wheat  be  more  highly  magnified,  the  structure 
of  its  various  components  can  be  made  out  in  greater  detail.     One 


Fig.  16 — Section  through  Part  of  a  Wheat  Grain  (more  highly 
magnified). 

a.  Honeycomb  of  cellulose  ;  b,  starch  grains  ;  c,  particles  of  gluten. 

can  then  see  (Fig.  16)  that  the  endosperm  consists  of  a  delicate 
honeycomb  of  cellulose,  the  cavities  of  which  are  crammed  full  of 
starch  grains,  the  interstices  being  filled  up  by  smaller  particles 
consisting  of  a  protein  or  mixture  of  proteins  called  gluten.     The 

'  The  first  three  analyses  are  by  Professor  Church. 

^  The  germ  contains  6-44  per  cent,  of  nitrogen,  of  which  oSo  gramme  is  in  the 
form  of  amides  (Frankfurt,  Landtmrtk.  versuchs  Stat.,  1896,  xlvii.  449). 
*  Most  of  this  is  in  a  soluble  form. 


iga  FOOD  AND  DIETETICS 

gluten  granules  are  most  abundant  in  the  outer  zones  of  the  endo- 
sperm. 

The  relative  proportions  of  starch  and  gluten  differ  in  different 
kinds  of  wheat.  Generally  speaking,  it  may  be  said  that  those 
grains  which  look  hard,  translucent,  and  horny  on  section,  are  rich 
in  gluten  and  poor  in  starch  ;  while  for  the  grains  which  are  soft, 
opaque,  and  floury  on  section,  the  reverse  holds  good. 

The  bran  is  found  to  consist  of  three  distinct  layers  : 

1.  An  outer  layer  consisting  entirely  of  fibres  of  cellulose  impreg- 
nated with  mineral  matter.  This  is  the  layer  which  is  removed  in 
the  decortication  of  wheat. 

2.  A  middle  layer  consisting  chiefly  of  small  cells  full  of  pigment, 
which  give  to  the  bran  its  brown  colour.  This  layer  is  much  poorer 
in  cellulose  than  the  first. 

3.  An  inner  layer  consisting  of  a  single  row  of  large  cells  full  of 
a  granular  matter,  which  is  a  protein  termed  aleurone.  This  layer  is 
sometimes  also  called  the  '  cerealin  '  layer.  It  contains  least  cellu- 
lose of  all. 

The  germ  consists  of  a  mass  of  small  cells  rich  in  protein  and  fat, 
but  its  more  minute  structure  does  not  concern  us  just  now. 

The  wheat  grain  may  be  used  as  a  food  in  its  entirety.  Soaked 
in  water  till  it  swelled  up  and  burst,  and  then  boiled  in  milk,  with 
the  addition  of  sugar  and  other  ingredients,  it  formed  the  old  and 
very  nourishing  dish  called  frumenty,  which  is  now,  however,  but 
seldom  seen  on  the  table. 

Far  more  commonly  it  is  reduced  before  eating  to  a  state  of  meal 
or  flour  by  the  process  of  grinding  or  milling.  Now,  it  is  an  exceed- 
ingly difficult  matter,  owing  to  its  toughness,  to  reduce  the  bran  of 
wheat  to  a  powder  by  grinding.  It  can  be  done,  but  the  trouble 
and  expense  entailed  are  so  great  that  one  of  the  miller's  first  objects 
is  to  remove  it  altogether.  In  the  old  method  of  stone  grinding  the 
bran  was  removed,  but  the  germ  was  left,  the  meal  or  flour  con- 
sisting of  the  products  of  the  germ  and  endosperm  together.  In  the 
elaborate  processes  of  modem  roller  milling,  however,  the  germ  also 
is  removed,  but  for  a  different  reason  from  the  bran.  It  is  found 
that  the  oil  which  is  contained  so  abundantly  in  the  germ  is  apt  to 
become  rancid,  so  spoiling  the  flour,  while  the  soluble  proteins  which 
are  present  in  that  part  of  the  grain  are  apt  to  act  upon  the  starch 
of  the  flour,  converting  part  of  it  into  soluble  forms  (dextrin  and 
sugar),  which  darken  in  colour  in  the  oven  and  detract  from  the 
appearance  of  the  bread.  So  the  germ  is  got  rid  of  also,  its  removal 
being  facilitated  by  the  fact  that  its  toughness  causes  it  to  become 


BRAN— MILLING  193 

flattened  out  in  the  process  of  milling,  while  the  more  brittle  endo- 
sperm is  reduced  to  a  fine  powder,  which  can  be  separated  by  sifting. 

Hence  it  comes  about  that  in  the  process  of  milling,  to  which  the 
whole  grain  is  subjected,  its  different  parts  are  broken  up,  various 
mill-products  being  produced.  The  outer  coat  yields  '  bran,'  '  fine 
pollards,'  *  sharps '  and  '  middlings,'  which  represent  different 
fragments  of  it  from  without  inwards,  the  germ  is  removed  as 
'  offal,'  while  the  '  flour  *  is  derived  solely  from  the  endosperm. 

To  the  whole  of  the  flour  so  derived  the  term  '  straight-run '  or 

*  straight-grade  '  is  applied,  and  the  yield  of  it  is  about  70  per  cent. 
of  the  weight  of  the  original  grain.  By  mechanical  processes  this 
can  be  further  divided  into  a  small  quantity  of  patents,  and  a  large 
quantity  of  '  bakers  '  or  '  households.'  The  former  is  derived  from 
the  central  part  of  the  endosperm,  and  if  prepared  from  ordinary 
wheat  is  consequently  rather  poor  in  protein,  but  very  rich  in  starch. 
Some  '  strong  '  wheats,  however,  e.g.,  Hungarian,  yield  a  *  patents' 
which  is  still  rich  in  gluten  ;  it  is  from  such  flour  that  genuine 
Vienna  bread  is  made.*  Owing  to  its  purity  of  colour,  '  patents'  is 
usually  reserved  for  the  preparation  of  fancy  breads  and  pastry. 

'Households'  flour  is  further  subdivided  into  (i)  second  patents,  or 

*  whites  ' ;  (2)  first  households  ;  (3)  second  households,  or  *  seconds.' 
The  first  of  these  is  derived  from  the  part  of  the  endosperm  nearest 
to  that  which  produces  '  patents  ';  the  last  emanates  from  the  outer 
layers,  just  under  the  bran ;  while  the  first  households  comes  from 
the  intermediate  part  of  the  endosperm.  Of  these  varieties, 
'  seconds '  is  richest  in  protein  (gluten),  '  whites  '  in  starch. 

Ordinary  bread  is  usually  made  from  a  mixture  of  '  whites '  and 

*  households,'  derived,  most  commonly,  from  a  blend  of  different 
wheats. 

A  blend  is  used  because  wheats  differ  in  composition,  some  being 
rich  in  gluten  and  poor  in  water  (*  strong '  wheats),  while  others  are 
more  starchy  and  contain  more  moisture.  Indian  wheat,  which 
has  only  about  8  per  cent,  of  water,  is  an  example  of  the  first  sort ; 
most  English  wheats  (14  per  cent,  moisture)  belong  to  the  second. 
The  '  strong '  wheats  take  up  most  water  on  baking,  and  hence  yield 
most  loaves.  This  is  the  explanation  of  the  apparent  paradox,  that 
the  larger  the  bulk  of  a  sack  of  wheat,  the  smaller  is  the  quantity  of 
bread  it  is  capable  of  yielding.  Another  advantage  of  blending  is 
that  the  deficiencies  of  one  kind  of  gluten  are  made  up  for  by  the 
excesses  of  another ;  for  gluten  is  a  composite  substance,  and  some 

^  British  wheat  seldom  contains  more  than  loper  sent,  of  gluten,  whilein  Eastern 
Europe  and  in  the  Western  States  of  America  the  proportion  may  be  over  20  per 
cent.     Hungarian  wheat  is  the  finest  and  '  strongest '  which  the  world  produces. 

13 


194  FOOD  AND  DIETETICS 

wheats  are  richer  in  some  of  its  constituents,  other  wheats  in  others, 
and  by  suitable  blending  a  flour  can  be  produced  which  is  not  only 
'  strong,'  but  has  also  a  good  colour  and  flavour. 

«  Seconds  '  flour  yields  a  bread  which  is  richer  in  protein  than  the 
product  of  most  blends  ;  but  the  loaf  is  apt  to  be  rather  dark  in 
colour,  and  on  that  account  not  highly  appreciated  by  the  public. 

An  analysis  has  been  made  by  Church''  of  some  of  these  mill- 
products  of  wheat,  which  brings  out  the  difference  in  the  proportion 
of  protein  they  contain,  to  which  reference  has  been  made  above. 
The  following  are  the  figures  : 

Protein.  Per  cent.  N.  Per  cent.  Fat. 

Wholewheat         169  2'02 

Flour  ('patents ') I'62  1-4 

„      ('seconds')..  ..         ..         ..     196  1'82 

Bran  214  275 

'Fine  sharps'        2-60  3*50 

It  should  be  added  that  a  considerable  proportion  of  the  nitrogen 
of '  sharps '  is  not  in  a  protein  form. 

The  following  table  shows  the  relative  composition  of  various 
milling  products  obtained  in  America^: 

Analyses  of  Whbat  and  the  Products  of  Roller  Milling. 


Wheat  as  it  enters  the  mill  . . 

First  break 

Sixth  break       ..  .. 

Bran 

Tailings  from  reduction  No.  5 

Second  perm 

Entire-wheat  flour 

Graham  flour    . . 

Patent  roller  process  flour  : 

Bakers'  grade 

Family  and  straight  grade 

High  grade . . 

Low  grade  . . 


Water. 


Per  cent. 

Q-66 

8-23 

7*66 

lo-gi 

1212 

11-4 
"■3 

11-9 
12-8 

I2'4 
12"0 


Protein. 


Per  cent. 
14-18 
14-18 
16-28 
16-28 
16-63 
33"25 
13-8 
133 

13*3 
10-8 
11-2 

140 


Fat. 


Percent. 
2-6l 

2-68 

5*34 

5  "03 

3-85 

I5'6l 

19 

2-2 

I-I 

I'D 

1-9 


Carbohydrates. 


Starch, 
etc 


Percent. 
69-94 

59*42 
56-21 

63*93 
35'I9 
71 -o 

70*5 

72-0 

74  "6 

747 
70-4 


Crude 
Fibre. 


Per  cent. 
170 
1*62 

5 '60 

5-98 
1-18 

175 

09 

0-6 

07 
0*2 
0-2 

0-8 


Ask 


Per  cent. 
1-91 
173 
5-68 

5  59 
229 

5  45 

i-o 

1-8 

0-6 
05 
o"5 
0-9 


Now,  in  rejecting  the  germ  and  the  bran  the  miller  undoubtedly 
discards  some  of  the  most  useful  chemical  constituents  of  the  wheat, 

*  It  is  very  desirable  that  the  semolina,  as  well  as  the  germ,  should  be  retained 
in  'seconds'  flour.  This  was  done  by  the  old  system  of  stone-milling  ;  but  when 
roller-mills  are  used  most  of  the  semolina  goes  into  the  '  patents  '  flour,  and  the 
ordinary  '  seconds  '  is  thereby  impoverished. 

•  '  Food  Grains  of  India,'  p.  95. 

'  United  States  Department  of  Agriculture,  Division  of  Chemistry,  Bull.  13, 
pp,  1226-1238,  and  Office  of  Experiment  Stations,  Bull.  28  (rev.  ed.),  pp.  57,  58. 


'HO VIS'  AND  'FRAME  FOOD'  PROCESSES        195 

£or  with  the  germ  protein  and  fat  are  lost,  and  with  the  bran  mineral 
matter  and  the  protein  contained  in  its  layer  of  aleurone  cells. 

The  recognition  of  this  waste  has  led  to  the  devising  of  two  patent 
processes  to  prevent  it.  The  first  of  these  deals  with  the  germ 
(Smith's  patent).  In  this  process  the  separated  germ  is  partially 
cooked  by  means  of  superheated  steam.  This  kills  the  ferment 
contained  in  the  soluble  proteins,  which,  as  we  have  seen,  acts  upon 
the  starch  of  the  flour.  The  steam  also  sterilizes  the  fat  of  the  germ, 
preventing  it  from  becoming  rancid,  and  so  spoiling  the  taste  of  the 
flour.  The  germ  so  treated  is  ground  to  a  fine  meal,  and  of  this 
one  part  is  added  to  three  of  ordinary  flour,  the  mixture  consituting 
'  Hovis '  flour.  It  is,  as  one  would  expect,  much  richer  in  protein 
and  fat  than  ordinary  flour  (see  table  below).  Since  the  discovery  of 
this  method  of  treating  the  germ,  many  similar  processes  have  been 
introduced,  and  *  germ  breads  '  are  now  of  frequent  occurrence  in  the 
market.  The  invention  of  them  marks  a  decided  advance  in  our 
methods  of  bread-making.^ 

The  second  patent  process  to  which  reference  has  been  made 
deals  with  the  bran.  It  is  the  '  Frame  Food '  process.  The  bran  is 
boiled  with  water  under  high  pressure,  the  result  of  which  is  to 
break  down  most  of  its  cellulose  and  to  extract  from  it  most  of  its 
mineral  constituents  and  part  of  its  nitrogen.  A  proportion  of  carbo- 
hydrate is  also  removed  in  a  soluble  form.  The  watery  extract  is 
filtered  and  evaporated  under  diminished  pressure  to  dryness.  In 
this  form  it  constitutes  *  Frame  Food  Extract.'  It  is  rich  in  mineral 
matter  and  nitrogen,  although  much  of  the  latter  is  probably  not 
present  in  a  protein  form.  The  extract  so  prepared  forms  the  basis 
of  various  preparations  manufactured  by  the  Frame  Food  Company, 
to  some  of  wl.ich  reference  will  be  made  later. 

The  following  table  shows  the  comparative  composition  of  the 
different  preparations  of  wheat  of  which  we  have  been  speaking  : 


Wheat- 
meal. 

Medium 

Flour 
(House- 
holds). 

Finest 

Flour 

(Patenu). 

Hovis 

Flour. 

Frame 

Food 

Extract. 

Water 

Nitrogenous  matter^ 

Fat            

Carbohydrates  (including 

cellulose) 
Ash            

I2-I 

142 

19 

70  6 
12 

12-3 

107 

II 

75-4 
0-5 

13-8 
7-9 
14 

764 
05 

I2'2 

15-5 

32 

700 
23 

98 

165 

ID 

639 

8-8 

1  A  liquid  extract  of  the  germ  which  contains  its  ferments  has  recently  been 
introduced  under  the  name  of  '  Eurissa."  It  has  much  the  same  uses  in  bread- 
making  as  malt-extracts  (see  p.  204).  '^  N  x  6"25. 


196  FOOD  AND  DIETETICS 

Cookery  of  Flour — Bread. 

In  order  to  make  flour  available  as  food,  it  must  be  cooked  in 
some  way  or  another.  The  simplest  method  is  to  mix  the  flour  with 
water  and  bake  it.  It  is  in  this  way  that  sliip's  biscuit  is  manu- 
factured. The  product,  however,  is  of  an  almost  flinty  hardness, 
and  not  easy  of  mastication.  Hence  the  problem  early  arose,  how 
to  cook  the  flour  in  such  a  way  that  it  would  be  light  and  easy  of 
digestion.  The  problem  was  solved  by  causing  gas  to  develop  in 
the  mixture  of  flour  and  water,  so  converting  the  latter  into  a  kind 
of  sponge,  which  was  subsequently  baked,  and  into  which  the 
digestive  juices  can  easily  penetrate.  In  other  words,  man  learnt  to 
make  bread.  Now,  the  making  of  bread  from  flour  is  only  possible 
because  the  latter  contains  gluten.  Gluten  is  a  protein,  or  mixture 
of  proteins,  which  has  the  peculiar  property  of  becoming  viscid 
when  mixed  with  water.  If  the  viscid  mass  is  then  blown  up  with 
gas,  it  has  sufficient  cohesion  to  remain  in  the  form  of  a  sponge  or 
honeycomb,  instead  of  collapsing  again,  as  it  otherwise  would  do,  and 
allowing  the  gas  to  escape.  Most  other  cereals,  such  as  barley,  rice, 
and  oatmeal,  do  not  contain  gluten,  but  other  forms  of  protein, 
which  do  not  become  viscid  when  moistened,  and  consequently  out 
of  these  bread  cannot  be  made. 

The  next  question  is.  How  is  the  gas,  which  is  to  be  used  to  blow 

up  the  dough,  produced  ?     The  reply  is  that  the  earliest  method  of 

producing  the  gas,  and  that  which  is  still  by  far  the  most  widely  used, 

was  by  fermentation.     There  are  certain  very  minute  plants,  called 

yeasts,  which  are  capable  of  breaking  up  sugar  in  such  a  way  as  to 

produce  from  it  carbonic  acid  gas  and  alcohol.     This  process  is  one 

of  '  fermentation  '  and  may  be  represented  by  the  following  chemical 

formula  : 

CjHjoOg        -  2CO5  +      2C2HgO. 

(i  molecule    yields    2  molecules    and   2  molecules 

of  sugar)  of  carbonic  of  alcohol. 

acid  gas 

The  yeast  is  used  to  manufacture  gas  out  of  the  sugar  contained  In 
the  dough.  But  where  does  the  yeast  come  from  ?  In  the  old  days — 
and  leaven  bread  was  known  to  the  Egyptians  in  the  time  of  Moses — 
it  simply  came  from  the  air.  Yeast  cells  appear  to  be  floating  about 
in  the  atmosphere,  and  when  they  meet  with  any  soil  on  which  they 
can  grow  they  start  there  and  produce  fermentation.  If  dough, 
therefore,  be  left  exposed  to  the  air,  yeast  cells  will  ultimately  find 
their  way  into  it,  and  start  to  grow  and  multiply,  and  produce  gas  in 
the  dough.     But  other  minute  plants,  bacteria,  get  into  the  dough 


BREAD-MAKING  I97 

at  the  same  time,  and  these  produce  acids  in  it  (especially  acetic  and 
lactic  acids),^  so  that  the  dough  not  only  ferments,  but  becomes  sour. 
It  was  this  sour  fermenting  dough  that  was  first  used  for  making 
bread.  It  was  called  leaven.  A  little  of  it  was  added  to  fresh 
dough,  and  the  yeast  which  it  contained  started  to  grow  with  great 
rapidity  through  the  fresh  dough  till  it  was  all  '  leavened,'  and 
filled  with  bubbles  of  gas.  Most  of  this  dough  was  then  baked,  but 
a  small  part  was  set  aside  as  the  *  leaven '  to  be  used  in  starting 
fermentation  in  a  fresh  batch  of  bread.  The  presence  of  the  acids 
in  this  leavened  bread  causes  it  to  have  a  sour  taste,  and  for  this 
reason  the  process  is  now  but  rarely  used.  The  black  sour  bread 
(pumpernickel)  met  with  in  North  Germany  is  still  made  by  a 
process  of  leavening. 

The  next  advance  upon  this  process,  which  must  have  been  intro- 
duced after  beer  was  known,  was  to  use  pure  yeast  obtained  from 
the  brewer,  and  thus  to  get  the  production  of  gas  in  the  dough  with- 
out the  development  of  acids.  In  more  recent  years  brewer's  yeast 
has  been  gradually  displaced  by  *  compressed '  or  *  German '  yeast, 
which  is  more  convenient  and  keeps  better.  It  consists  of  pure 
yeast  grown  in  a  special  way  and  purified  by  repeated  washing, 
after  which  it  is  compressed  into  cakes. 

In  using  yeast  to  make  bread,  the  first  thing  the  baker  has  to  do 
is  to  get  his  yeast  to  increase  and  multiply.  This  has  two  advan- 
tages :  it  enables  an  originally  small  quantity  of  yeast  to  suffice  for 
a  whole  sack  of  flour,  and  it  produces  a  more  active  yeast,  for  the 
young  cells  are  more  energetic  than  those  which  are  older.  This 
stage  of  bread-making  is  called  the  preparation  of  the  ferment. 
About  8  pounds  or  so  of  good  potatoes  are  taken  and,  after  being 
peeled,  are  boiled  down  to  a  thin  sort  of  gruel ;  2  pounds  of  flour 
are  added,  and  then  the  yeast  and  the  mixture  is  stirred  up  and  kept 
at  a  temperature  of  85°  F.  or  thereabouts.  The  yeast  derives 
abundant  nourishment  from  the  flour,  and  grows  and  multiplies  very 
fast.  The  nitrogenous  matter  of  the  flour  also  acts  upon  the  large 
starch  grains  of  the  potato,  converting  them  in  part  into  sugar, 
which  is  straightway  attacked  by  the  yeast.  After  about  five  hours 
or  so  the  process  comes  to  a  standstill,  but  the  whole  ferment  is  now 
swarming  with  young  and  active  yeast  cells.  A  quarter  or  a  third  of 
a  sack  of  flour  is  now  taken  and  thoroughly  mixed  with  the  ferment 
and  some  water   in   a   trough.     A   small   quantity  of  salt — about 

1  For  a  more  complete  description  of  the  changes  which  take  place  in  dough 
under  fermentation,  see  Weyl's  '  Handb.  d.  Hygiene.'  iii.  247. 


1 98  FOOD  AND  DIETETICS 

1^  ounce  for  each  quartern  loaf — is  usually,  but  not  always,  added. 
The  salt  acts  as  a  check  on  the  fermentation.  This  mixture  is 
spoken  of  technically  as  the  sponge.  The  young  yeast  cells  now  act 
upon  the  sugar  produced  from  the  flour,  and  alcohol  and  carbonic 
acid  gas  are  liberated  all  through  the  sponge.  The  gas  blows  the 
latter  up,  and  after  the  lapse  of  about  five  hours  the  top  breaks  and 
some  of  the  gas  escapes.  After  another  hour  has  elapsed  it  again 
breaks,  and  when  this  has  happened  the  rest  of  the  sack  of  flour  is 
added  along  with  some  more  water.  In  all  about  60  quarts  of  water 
are  used  for  every  sack  of  flour.  This  constitutes  the  dough.  It  is 
thoroughly  mixed  by  machinery,  and  then  left  for  an  hour  to  '  rise.' 
At  the  end  of  that  time  it  is  weighed  and  placed  in  the  oven  for  one 
and  a  half  hours  at  a  temperature  of  about  450°  F.  This  treatment 
causes  the  gas  in  the  dough  to  expand  and  blow  the  latter  up  so  that  it 
becomes  full  of  little  cavities.  The  heat  also  hardens  and  coagu- 
lates the  proteins  of  the  floor  in  the  outer  part  of  the  loaf,  where  the 
temperature  is  highest.  Some  of  the  starch  is  converted  into  soluble 
starch  and  dextrin,  and  forms  the  crust.  It  is  to  the  dextrin  that 
the  crust  owes  its  glazed  appearance.  Altogether  about  8  per  cent.^ 
of  the  starch  in  the  loaf  is  thus  converted.  Some  caramel  also  is 
formed,  and  helps  to  give  the  crust  its  flavour  and  dark  colour. 
When  these  changes  have  taken  place  the  dough  has  passed  into  the 
form  of  bread.  Six  bushels  of  wheat  go  to  make  a  sack  of  flour 
(280  pounds),  which  yields  under  the  above  method  of  treatment 
about  ninety-six  quartern  loaves.  In  other  words,  i  pound  of  bread 
can  be  obtained  from  about  §  pound  of  flour,  33  per  cent,  of  water 
being  taken  up  in  the  dough. 

It  must  not  be  supposed  that  the  method  of  bread-making  is 
everywhere  precisely  identical.  The  above  is  the  process  as  prac- 
tised in  London,  but  the  details  vary  somewhat  in  different  localities. 
Thus,  some  bakers  add  the  ferment  to  the  whole  of  the  flour  right 
away.  Others  omit  the  ferment  stage,  and  begin  by  making  a 
'  sponge,'  which  is  afterwards  added  to  the  dough. 

Scotch  bakers  prepare  first  a  '  barm,'  which  is  a  mixture  of  malted 
flour,  sugar  and  hops,  and  from  this  make  their  '  sponge.'^  They 
also  add  more  salt  than  is  usual  here  ;  hence  the  more  marked 
flavour  of  Scotch  bread. 

Now,  it  will  be  obvious  that  any  process  of  making  bread  by 
fermentation  necessarily  implies  a  certain  amoimt  of  waste.     Some 

*  Bull.  67,  United  Sutes  Department  of  Agriculture,  1899. 

•  See  '  Practical  Bread-making,'  by  F.  T.  Vine;  London,  1897. 


LOSSES  IN  BAKING  199 

at  least,  of  the  starch  in  the  flour  is  lost  by  being  split  up  first  into 
sugar,  and  then  into  alcohol  and  carbonic  acid  gas.  The  gas  is  of 
no  use  from  a  nutritive  point  of  view,  and  the  alcohol  is  mostly 
driven  off  by  the  heat  of  the  oven.  It  has  been  calculated  by 
Graham^  that  300,000  gallons  of  alcohol  are  annually  lost  in  this  way 
in  the  ovens  of  London  alone.  A  patent  was  taken  out  more  than 
fifty  years  ago  for  collecting  this  alcohol,  but  the  process  did  not 
pay  in  practice.  A  small  quantity  of  this  alcohol  does  remain  in 
the  bread,  perhaps  about  16  grains  in  each  loaf.  In  a  paper  in  the 
Chemical  News  (1873)  it  was  computed  that  forty  2-pound  loaves 
contain  as  much  alcohol  as  a  bottle  of  ordinary  port.  Bolas  found 
o*22  to  0*40  per  cent,  alcohol  in  new  bread. 

Jago^  states  that  in  all  about  1*3  per  cent,  of  the  nutritive 
ingredients  used  in  bread-making  are  lost  in  the  course  of  the 
operations.  Very  exact  observations  on  this  point  have  been  made 
in  a  bakery  at  Pittsburg.  It  was  found  that  1-3  per  cent,  of  the 
proteins,  71*2  per  cent,  of  the  fats,  and  3*2  per  cent,  of  the  carbo- 
hydrates in  the  ingredients  disappeared  in  the  process  of  baking. 
The  total  loss  of  nutritive  material,  reckoned  in  Calories,  was  about 
5  per  cent.  The  very  great  loss  of  fat  is  striking,  and  has  been 
confirmed  by  observations  made  at  New  Brunswick.^  in  which  the 
fat  in  the  original  flour  had  diminished  nearly  60  per  cent,  by  the 
time  the  bread  was  completed.  It  would  appear  that  the  fat  is 
volatilized  by  the  heat  of  the  oven. 

Fully  fifty  years  ago  experiments  were  made  in  Glasgow  by 
Dr.  Dundas  Thomson,  which  showed  that  a  sack  of  flour  would 
yield  107  loaves  of  unfermented  bread,  and  only  100  loaves  of 
fermented  bread.'* 

The  consideration  of  this  inevitable  waste  has  led  to  attempts  to 
convert  dough  into  a  porous  form  by  other  methods  than  that  of 
fermentation.  One  of  these  is  the  method  of  Dauglish.  In  this 
process  the  gas  is  prepared  from  chemical  substances.  Water  is 
saturated  with  it,  and  is  mixed  with  the  flour  under  pressure  in 
air-tight  chambers.  The  pressure  in  these  is  then  lowered  by 
opening  a  trap,  and  the  dough  is  forced  out  and  blown  up  by  the 
expanding  gas.  It  is  next  cut  into  loaves,  and  the  rest  of  the  baking 
is  quickly  completed  in  the  usual  way.     The  product  is  known  as 

*  '  Chemistry  of  Bread-making,'  Cantor  Lectures,  1879. 
'  Jago,  '  Science  and  Art  of  Bread-making.' 

»  Voorhees,  United  States  Department  of  Agriculture,  Office  of  Experiment 
Stations,  Bull.  53;  see  also  ibid..  Bull.  67. 

*  'The  Food  of  Animals,'  p.  183;  London,  1846. 


200  FOOD  AND  DIETETICS 

aerated  bread.  It  is  quite  as  porous  as  that  produced  by  fermenta- 
tion, but  is  found  by  some  people  to  have  a  rather  '  raw  '  and  insipid 
taste.  This  is  apparently  to  be  attributed  to  the  absence  of  certain 
bye-products  which  yeast  produces  in  the  course  of  its  growth. 
Hence,  the  bread  has  not  met  with  universal  favour,  in  spite  of  its 
more  economical  mode  of  production.  The  process  would  appear 
to  be  specially  suited  for  the  making  of  wholemeal  bread,  for  it 
deprives  the  proteins  of  the  bran  of  the  opportunity  of  converting 
some  of  the  starch  of  the  flour  into  soluble  forms,  to  which  soluble 
substances  much  of  the  moistness  and  heaviness  of  ordinary  whole- 
meal bread  is  to  be  attributed. 

Results  similar  to  the  above  are  also  obtained  by  the  use  of 
baking-powders.  These  consist  of  mixtures  of  various  chemical 
substances,  which  have  this  in  common,  that  when  moistened  the 
ingredients  of  the  powder  act  upon  one  another,  carbonic  acid  being 
given  off.  If,  therefore,  the  powder  has  been  thoroughly  mixed 
with  the  flour,  and  water  be  added,  the  gas  will  be  Hberated  all 
through  the  resulting  dough,  and  the  latter  will  be  thoroughly 
aerated.  A  Lancet  Commission,  which  inquired  into  the  composition 
of  these  powders  some  years  ago,*  reported  that  the  majority  of 
them  were  pure,  consisting  of  a  mixture  either  of  tartaric  acid  or 
bitartrate  of  potash  with  bicarbonate  of  soda.  A  few  of  them, 
however,  contained  alum,  and  these  leave  some  alumina,  or,  more 
probably,  hydrated  oxide  of  aluminium,  in  the  bread. ^  The 
tartaric  acid  powders  are  the  most  efficient,  for  they  give  off 
twenty-five  times  their  volume  of  gas  ;  the  cream  of  tartar 
powders  yield  only  thirteen  volumes,  and  alum  powders  not  more 
than  seven  to  eleven.  In  all  of  these  powders  the  soda  is  slightly 
in  excess,  so  that  the  end  reaction  of  the  chemical  process  is 
alkaline.  There  is  thus  no  possibility  of  their  rendering  the 
bread  sour.  *  Self-raising  '  flour  is  flour  with  which  baking-powder 
has  already  been  mixed. 

No  matter  by  what  process  a  loaf  is  made,  it  possesses,  when 
finished,  certain  characters  by  which  bakers  judge  of  its  quality.  It 
should  be  well  '  risen,*  and  possessed  of  a  thin  flinty  crust,  which  is 
neither  very  light  nor  very  dark  in  colour,  and  cracks  on  breaking. 
The  crumb  should  be  elastic  in  consistence,  of  uniform  texture 
without  large  holes,  and  of  a  smooth  and  silky  '  pile.'  It  should 
have  a  sweet,  nutty  flavour  and  odour,  and  in  colour  should  be  of  a 
creamy  whiteness.     Curiously  enough,  when  bakers  speak  of  a  loaf 

*  Lancet,  1894,  i-  562. 

2  Some  also  contain  considerable  quantities  of  calcium  sulphate,  which  is 
open  to  objection  on  hygienic  grounds. 


THE  LOAF 


201 


^^^ 

"^^•l 

/^^^^ 

^^ATE_IR^ 

£'"^i'i'x^- 

GA 

CAR30HYDRATE 

51  i   •/. 

\pROTEiri    6i% 

\^^T  ij,  MI.V   M/iT 

— ^-^-= 

Fig.  17. — Diagrammatic  Representatiom 
OF  THE  Composition  of  a  Loaf. 


having  *no  colour,'  they  mean  that  it  is  rather  dark,  whereas  '  high 
colour'  signifies  with  them  great  whiteness.  It  must  be  admitted, 
however,  that  the  above  characters,  however  important  aesthetically, 
are  not  of  much  value  from  a  nutritive  point  of  view.  Especially  is 
this  so  in  regard  to  colour.  A  very  white  loaf  means  a  loaf  in  which 
starch  is  at  a  maximum  and 
protein  at  a  minimum,  and  that 
is  certainly  not  desirable.  For 
setting  up  a  false  standard  of 
whiteness  the  baker  is  not  to 
blame.  It  is  the  ignorance  of 
the  public,  which  mistrusts  a 
dark  loaf. 

The  Chemical  Composition 
OF  Bread. 

Two-thirds  of  the  volume  of 
a  good  loaf  is  made  up  of  gas^ 
(Fig.  17),  and  of  the  solid  part 
about  40   to    50  per   cent,   by 

weight  consists  of  water,  so  that  bread  is  one  of  the  least  watery  of 
vegetable  foods,  and  is  relatively  much  less  so  than  raw  meat.^  The 
cnmposition  of  the  dry  residue  will  obviously  depend  upon  that  of 
the  flour  from  which  the  bread  has  been  made.  Especially  has  one 
to  consider  whether  the  bran  and  the  germ  have  been  left  in  the 
flour  or  not.  In  white  bread  these  have  been  excluded.  As  regards 
*  brown '  breads  one  cannot  speak  so  definitely,  for  the  term  brown 
bread  is  a  vague  expression.'  It  may  simply  mean  that  a  certain 
proportion  of  bran  or  of  germ  or  of  both  have  been  added  to  the  flour, 
or  it  may  be  applied  to  bread  made  from  whole  wheat  meal.  In 
each  case  the  resulting  loaf  will  be  'brown.'  Now,  bran  contains, 
as  we  have  seen,  a  good  deal  of  mineral  matter  and  protein.  One 
would  naturally  expect,  therefore,  that  bread  containiir-  bran  should 
be  richer  in  these  ingredients  than  white  bread.  As  regards  mineral 
matter  this  is  certainly  true,  but  it  is  by  no  means  invariably  true  of 

1  See  Lehmann,  Archiv  f.  Hygiene,  1894,  xxi.  215. 

*  The  great  variability  in  the  amount  of  water  met  with  in  bread  renders  it 
desirable  that  some  standard  of  moisture  should  be  fixed,  the  exceeding  of  which 
should  be  regarded  as  an  adulteration.  In  other  words,  when  a  consumer  pays 
for  a  given  weight  of  bread  he  has  a  right  to  expect  that  his  purchase  shall 
contain  a  definite  amount  of  nutriment. 

'  '  Graham  flour,"  invented  by  the  American  physician,  Dr.  Sylvester  Graham, 
alone  contains  the  entire  grain.  In  making  '  entire-wheat  flour  '  the  outer  and 
more  flinty  layers  of  the  bran  are  removed. 


202  FOOD  AND  DIETETICS 

protein  The  following  table  shows  in  round  numbers  the  mean 
percentage  composition  of  several  white  and  wholemeal  breads 
analyzed  by  the  writer,  and  it  will  be  noticed  that  the  protein  is 

COMPOSITION  OF  WHOLEMEAL  AND  WHITE  BREAD  COMPARED. 

White  Wholemeal. 

Water       .,         ..         ..         ..         ..  400  450 

Proteini 6-5  6*3 

Fat            ,.,         ..  i-o  1-2 

Starch,  sugar  and  dextrin       .,         ..  5i-2  44 '8 

Cellulose..         ..         ..         .,         ..  03  i"5 

Mineral  matter  . .         . .         . .         . .  i  'o  i  '2 

really  more  abundant  in  the  white  bread.  These  results  are  con- 
firmed by  the  following  analyses  by  Atwater  -.^ 

Txr  ^  r>     ,  .  Mineral 

Water.  Protean.        ^j^^^^^^ 

White  bread  ».         ».         ..     35*4  95  i"i 

Brown  bread  ..         ..         ..     40  o  50  i"9 

Graham  bread         323  8-5  i"5 

Bell  also  says  :^  '  Contrary  to  the  views  sometimes  put  forward  by 
the  advocates  of  the  use  of  wheatmeal  bread,  the  samples  of  house- 
hold flour  submitted  to  analysis  were  found  richer  in  nitrogenous 
matter  than  the  entire  wheat  grain.'  In  some  recent  studies  of  breads 
made  in  America,''  the  following  conclusions  were  arrived  at : 

1.  Seventeen  samples  of  bread  from  'bakers'  and  'patents'  had 
9^  per  cent,  protein. 

2.  Bread  from  imitation  whole  wheat  flour  had  less  protein  than 
the  above.  That  from  true  wholemeal  {i.e..,  no  germ  removed)  had 
I  per  cent.  more. 

It  must  be  added  that  these  breads  were  apparently  considerably 
drier  than  ours  (32-9  and  33-8  per  cent,  water  respectively).  The 
authors  add  that  no  conclusions  can  be  drawn  from  these  figures 
regarding  their  nutritive  value. 

The  difference  in  brown  bread  is  partly  due  to  the  amount  of 
water  present.  The  '  protein  '  of  the  bran  converts  some  of  the 
starch  into  dextrin,  and  this  keeps  the  brown  bread  moist.  In 
carbohydrates  brown  bread  is  decidedly  poorer  than  white.  Not 
only  so,  but  about  2  per  cent,  of  the  carbohydrates  consists  of  the 
comparatively  useless  cellulose. 

^  N  X  57.  According  to  Rubner,  only  72  per  cent,  of  the  nitrogen  of  bread  is  in 
a  protein  form. 

*  '  Chemical  Composition  of  American  Food  Materials.' 
'  'Analysis  and  Adulteration  of  Foods.' 

*  Bull.  67,  United  States  Department  of  Agriculture  (Office  of  Experiment 
Stations). 


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204  FOOD  AND  DIETETICS 

In  analyzing  these  breads  the  nitrogen  was  estimated  by 
Kjeldahl's  process,  and  the  protein  calculated  from  it,  using  the 
factor  5*7.  The  ash  was  determined  in  the  usual  way.  The  carbo- 
hydrates were  estimated  by  difference.  Only  a  few  fat  estimations 
were  made,  the  fat  being  usually  included  in  the  carbohydrates 
owing  to  the  small  amount  of  it  present,  and  its  unimportance  as 
a  nutritive  constituent  of  bread  (it  may  be  taken  to  be  usually  less 
than  i^  per  cent.).  The  bread  was  analyzed  in  each  case  on  the 
day  after  baking. 

There  are  also  various  patent  and  fancy  breads  in  the  market.  Of 
the  former  the  different  varieties  of  Vienna  bread  are  a  good 
example.  These  are  made  from  very  fine  flour  (*  patents ')  fermented 
with  compressed  yeast,  milk  being  often  added  to  the  dough.  The 
crust  is  glazed  by  being  subjected  to  the  action  of  overheated  steam 
before  leaving  the  oven.  Of  the  patent  breads,  the  majority  are  of 
the  '  brown  '  variety.  They  are  made  from  flours  prepared  by  various 
patent  processes.  Some  of  them  are  wholemeal  breads,  in  which 
the  bran  has  been  reduced  to  varying  degrees  of  fineness ;  others 
contain  the  germ  in  various  proportions,  of  which  *  Hovis '  is  the 
best-known  example.  Others,  again,  are  malted.  The  malting  of 
bread  consists  in  adding  to  it  malt-extract,  obtained  by  evaporating 
an  infusion  of  malted  barley  to  a  syrupy  consistency  at  a  low 
temperature.  The  solid  part  of  the  malt-extract  so  prepared  consists 
mainly  of  malt- sugar  and  dextrins.  But  it  also  contains  the  ferment 
diastase,  which  is  able  to  convert  starch  into  soluble  substances 
(maltose  and  dextrin).  When,  therefore,  malt-extract  is  mixed  with 
the  dough  part  of  the  starch  of  the  latter  is  ultimately  converted 
into  malt-sugar  and  dextrin.  In  other  words,  part  of  the  starch  is 
digested.  This  has  the  effect,  as  already  pointed  out,  of  making  the 
bread  keep  longer  moist.  Now,  it  is  important  to  remember  that 
this  ferment  diastase  is  readily  killed  if  exposed  to  a  high  temperature. 
Hence  its  activity  inevitably  ceases  as  soon  as  the  bread  enters  the 
oven.  If,  then,  any  considerable  part  of  the  starch  of  the  dough  is 
to  be  converted,  the  malt-extract  must  be  added  very  early  in  the 
process.  As  an  alternative  to  that  it  may  be  added  to  a  separate 
part  of  the  flour,  and  the  latter  mixed  with  water  and  kept  at  a 
moderate  temperature  till  most  of  its  starch  has  been  changed,  and 
this  mixture  added  to  the  dough  just  before  baking.  This  is  the 
peculiarity  of  Montgomerie's  process,  by  which  '  Bermaline  *  bread  is 
made.  But  even  under  these  favourable  conditions  not  much  more 
than  lo  per  cent,  of  the  carbohydrates  of  the  loaf  are  in  a  soluble 


MALTED  BREADS  205 

form,  while  in  ordinary  bread  about  4  per  cent,  is  so  changed. 
Seeing,  also,  that  the  diastase  is  killed  by  the  act  of  baking,  it  is 
obvious  that  malted  bread  cannot  truly  be  said  to  aid  the  digestion 
of  other  starchy  foods.  In  the  preceding  table  the  composition  of 
most  of  the  patent  breads  is  shown  from  analyses  made  by  the 
author. 1  The  special  peculiarities  of  each  kind  are  also  briefly 
indicated.  We  shall  consider  the  nutritive  and  economic  value  of 
these  breads  later.  The  comparative  composition  of  the  crust  and 
crumb  of  white  bread  is  given  by  Barral  as  follows : 

Crust.  Crumb . 

Water 1715  4445 

Insoluble  protein       730  592 

Soluble          ,.             5-70  075 

Dextrin  and  sugar 488  379 

Starch 62-58  43-55 

Fatty  matters 118  070 

Ash        I-2I  084 

The  most  striking  point  about  these  figures  is  the  much  larger 
proportion  of  solids  in  the  crust,  and  the  larger  amount  of  soluble 
proteins  and  carbohydrates  which  it  contains. 

Changes  which  Bread  undergoes  on  Keeping. 

When  bread  is  kept  it  becomes  dry  from  loss  of  water.  The  loss, 
however,  is  not  a  very  rapid  one.  The  following  are  the  average 
results  of  fifty  observations  by  Goodfellow '} 

A  2-lb.  Loss 

Loaf  loses  per  cent. 

In  labours          ..         ..         ..         ..       ?    oz.  09 

,.  24      .,              f     ..  20 

„  36      ..              If     ■•  50 

..    48        ..  2H    ..  80 

„  60      „  3^     M  ii'o 

„  72       „  4i      ..  140 

At  the  end  of  a  week  14  per  cent,  of  the  original  water  is  gone, 
and  after  a  month  18  per  cent.  (v.  Bibra).  The  bread  also  becomes 
stale.  The  staleness  is  not  entirely  due  to  the  loss  of  water,  for,  as 
was  long  ago  shown  by  Boussingault,  one  has  merely  to  heat  the 
loaf  up  again  to  a  temperature  of  about  300°  F.  in  order  to  restore 
much  of  its  freshness.  Yet  in  the  course  cf  this  rebaking  it  loses 
considerably  more  water  than  it  had  already  lost  by  evaporation. 
The  explanation  of  this  rather  surprising  result  is  not  yet  clear.     It 

*  In  addition  to  the  breads  described  in  the  table,  mention  may  be  made  of 
•Turog,'  which  is  a  malted  brown  bread  made  from  flour  derived  from  various 
cereals,  and  '  Bananine  '  bread,  which  contains  banai\a  flour. 

^  •  Dietetic  Value  of  Bread,'  p.  139. 


2o6 


FOOD  AND  DIETETICS 


may  be  that  in  fresh  bread  there  is  some  free  water  present,  which 
becomes  united  with  starch  or  gluten  as  the  bread  grows  stale,  and  that 
the  rebaking  sets  it  free  again.  That  is  the  explanation  of  v.  Bibra,^ 
who  has  also  shown  that  the  freshness  will  not  return  if  the  bread 
has  already  lost  30  per  cent,  of  its  water.  Mattieu  Williams,^  on 
the  other  hand,  believes  that  the  staling  of  bread  is  due  to  the 
shrinkage  and  coming  together  of  the  fibres  which  form  the  walls 
of  its  visible  pores.  The  water  vapour  generated  by  the  rebaking 
drives  these  fibres  apart  again.  Boutroux'  has  still  another  explana- 
tion. He  believes  that  the  apparent  dryness  of  stale  bread  is  due  to 
a  shifting  of  moisture  from  the  crumb  to  the  crust.  When  first 
taken  from  the  oven  the  dry  crust  cools  quickly,  whilst  the  moist 
crumb  retains  its  heat  much  longer  ;  but  as  its  temperature  gradually 
falls  the  moisture  which  it  contains  tends  to  distil  outwards  into  the 
crust.  When  the  loaf  is  rebaked  the  moisture  is  driven  back  again 
into  the  crumb. 

The  cooking  of  bread  is  practically  confined  to  the  application  of 
dry  heat.  This  has  the  eflfect  of  driving  off  water,  and  of  rupturing 
some  of  the  starch  grains,  and  converting  them  partly  into  soluble 
starch  and  dextrin.  A  little  caramel  also  is  produced.  The  result 
is  toast.  '  Pulled  bread '  is  made  by  pulling  out  the  interior  of  a 
new  loaf  and  thoroughly  baking  it.  The  same  changes  occur  in  it 
as  in  toast,  only  to  a  greater  degree. 

Biscuits  are  made  from  fine  flour  either  alone  or  with  the 
addition  of  sugar,  butter,  milk,  flavouring  agents,  etc.  Baking- 
powder  is  sometimes  added  to  make  them  rise  a  little.  They  con- 
tain very  little  water  (about  5  per  cent.),  and  3  pounds  of  them  may 
be  taken  as  equal  in  nourishment  to  5  pounds  of  Dread  (Church). 
The  following  table  shows  an  analysis  of  some  by  Bauer  : 

COMPOSITION  OF  BISCUITS. 


Water 
Nitrogenous  matter 

Fat 

Sugar 

Other  carbohydrates 
Cellulose     . . 
Mineral  matter 


Fine  Wheaten 

Other  Wheaten 

English 

Biscuits. 

Biscuits. 

Biscuits. 

i-i8 

10  07 

745 

13-31 

II  93 

718 

318 

747 

9  28 

712 

3638 

1702 

7396 

32-29 

5808 

025 

075 

0  16 

i-o 

I-I4 

0  83 

^  V.  Bibra,  'Die  Getreidearten  und  das  Brot,'  Niirnberg,  i860;  see  also 
Lehmann,  Archiv  f.  Hygiene,  1894,  xxi.  215. 

'  '  Chemistry  of  Cookery,'  p.  209. 

*  Cited  in  '  Bread  and  the  Principles  of  Bread-Making,'  United  States  Depart' 
ment  of  Agriculture.  Farmers'  Bulletin,  No.  112,  p.  29,  1900. 


BISCUITS  AND  RUSKS  207 

Rusks  may  be  regarded  as  a  kind  of  toast.  They  are  made  in 
much  the  same  way  as  bread,  but  with  the  addition  of  butter,  sugar 
and  milk,  and  are  twice  passed  through  the  oven,  after  which  they 
are  thoroughly  dried. 

In  the  next  chapter  we  shall  consider  the  digestibility  and  nutritive 
value  of  bread. 


£ao8J 


CHAPTER  XII 

BREAD  {continugd)—OT'SER  CEREALS 

Digestibility  and  Absorption  of  Bread. 

The  digestion  of  bread  takes  place,  in  part  at  least,  in  the  mouth, 
by  the  conversion  of  its  starch  into  dextrins  and  maltose  under  the 
action  of  the  saliva.  The  more  thoroughly  bread  is  chewed  and 
ground  into  particles,  the  more  complete  will  the  transformation  of 
the  starch  be.  It  is  on  account  of  the  greater  ease  with  which  they 
can  be  pulverized  by  the  teeth  that  toast  and  biscuits  are  more 
easily  digested  than  ordinary  bread  and  stale  bread  than  a  newly- 
baked  loaf.  The  dryness  of  toast  and  biscuits,  too,  enables  them 
to  become  easily  saturated  with  the  saliva,  and  that  also  greatly 
facilitates  digestion.  Further,  it  must  be  remembered  that  a 
considerable  proportion  of  the  starch  in  biscuits  and  toast  has  been 
already  converted  into  soluble  forms  in  the  course  of  their  prepara- 
tion, so  that  the  labours  of  the  digestive  juices  in  their  case  are 
considerably  lightened.  For  these  reasons  also  the  crust  of  bread  is 
more  digestible  than  the  crumb,  for  it  is  drier,  and  contains  a  higher 
proportion  of  carbohydrates,  owing  to  the  more  intense  action  upon 
it  of  the  heat  of  the  oven. 

The  notorious  indigestibility  of  new  bread,  on  the  other  hand,  is 
due  to  its  moistness,  which  makes  it  difficalt  to  chew,  and  at  the 
same  time  prevents  it  from  soaking  up  the  saliva. 

As  regards  the  durationxof  its  stay  in  the  stomach,  bread  occupies 
a  middle  position  among  the  vegetable  foods,  70  grammes  (2  J  ounces, 
or  an  ordinary  slice)  having  completely  left  the  stomach  in  two  hours 
and  twenty  minutes,  while  150  grammes  (5^  ounces,  or  two  rather 
thick  slices)  remain  about  an  hour  longer.  These  periods  cannot  really 
be  regarded  as  long  when  one  bears  in  mind  the  comparatively  large 
amount  of  solid  matter  which  bread  contains.^  White  bread  is 
^  Penzoldt,  Dtut.  Archiv/.  Klin.  Med.,  1893,  U.  333. 


ABSORPTION  OF  WHITE  BREAD  309 

disposed  of  by  the  stomach  rather  more  quickly  than  black  (e.g., 
pumpernickel),  but  there  is  no  appreciable  diflference  in  this  respect 
between  the  behaviour  of  wholemeal  bread  and  that  made  from  fine 
flour.  The  presence  of  bran  in  wholemeal  bread,  however,  may  act 
as  ballast  in  the  stomach,  and  give  to  it  the  greater  '  sustaining  * 
power  with  which  it  is  commonly  credited.  Considering  the  large 
amount  of  solid  nutriment  which  they  contain,  biscuits  must  be 
regarded  as  considerably  more  digestible  than  ordinary  bread. 

New  bread,  unless  very  thoroughly  chewed,  offers  greatei 
resistance  to  the  stomach  than  stale  bread,  owing  to  its  tendency  to 
form  doughy  masses. 

In  the  intestine  the  digestion  of  the  starch  and  protein  of  bread  is 
completed,  and  absorption  takes  place.  On  the  whole,  white  bread 
is  very  thoroughly  absorbed.  Even  when  large  quantities  are 
consumed,  the  loss  of  nutritive  constituents  is  only  about  as  follows  :* 

Percentag$ 
unabsorbed. 
Total  solids         ••        ••        ••        ••        «.      4i 

Protein 20 

Mineral  matter 25 

Carbohydrates «         ..       3 

It  will  be  noted  that  the  greatest  share  of  loss  falls  to  the  proteins, 
of  which  about  one-fifth  escapes  absorption.  This  contrasts  very 
strikingly  with  the  case  of  meat,  in  which  the  protein  is  absorbed 
almost  in  its  entirety. 

The  defective  absorption  of  the  proteins  in  bread  is  apparently  due 
in  part  to  the  large  amount  of  starch  present  ;2  in  part,  also,  it  may 
be  only  apparent,  and  explicable  by  the  fact  that  bread  requires  a 
large  production  of  the  digestive  juices  for  its  complete  solution 
(see  also  p.  11). 

The  above  experiments  apply  to  cases  in  which  bread  formed  the 
main  part  of  the  diet.  When  given  along  with  other  foods,  its 
absorption  appears  to  be  considerably  increased.  Thus,  five  experi- 
ments on  an  exclusive  bread  diet  showed  an  average  absorption  of 
82  per  cent,  of  the  protein  and  99  per  cent,  of  the  carbohydrates. 
When  2  litres  (3^  pints)  of  milk  were  added  to  the  diet,  the  absorption 
of  protein  rose  to  97  per  cent,  while  that  of  the  carbohydrates 
remained  stationary.    Ten  experiments  on  milk  alone  showed  a 

From  the  average  of  a  considerable  number  of  experiments  by  Rnbner, 
Atwater,  Zuntz  and  Magn    -Levy,  Goodfellow  and  others.     Tbe  qoantities  con- 
samed  were  very  considera.  ;e.  amounung  to  from  600  to  1,000  grammes  per  day. 
'  See  experiments  by  Meyer,  Zeit.  f.  Biolog.,  187X,  vii.  1. 

14 


210  FOOD  AND  DIETETICS 

protein  absorption  of  92  per  cent.,  and  an  absorption  of  the  carbo- 
hydrates to  86^  per  cent.^ 

This  is  another  instance  of  the  general  rule,  that  a  mixture  ol 
foods  is  better  absorbed  than  any  one  food  by  itself. 

The  carbohydrate  of  bread  corresponds  to  the  protein  of  meat  in 
being  almost  completely  absorbed  into  the  blood.  On  the  other 
hand,  it  is  rather  surprising  to  find  that,  of  the  comparatively  small 
amount  of  mineral  matter  met  with  in  bread,  one-fourth  is  excreted 
unabsorbed.  Seeing  that  this  is  the  case,  if  is  surely  futile  to 
recommend  the  use  of  bread  containing  a  larger  amount  of  mineral 
constituents. 

Relative  Absorption  of  White  and  Wholemeal  Bread. 

Brown  and  wholemeal  breads  differ  from  white  bread,  as  we 
have  already  seen,  in  containing  more  or  less  of  the  bran  of  the 
wheat.  Any  difference  which  they  show  in  absorbability,  therefore, 
when  compared  with  white  bread,  will  depend  probably  on  this 
peculiarity. 

Now,  bran  contains  a  large  amount  of  cellulose,  some  analysts 
placing  the  proportion  as  high  as  20  per  cent,  or  more.'  Not  only 
so :  the  cellulose  of  bran  is  in  a  dense  and  woody  form.  It  has 
already  been  pointed  out  that,  at  the  best,  cellulose  is  but  imper- 
fectly digested  by  man,  and  that  when  it  becomes  woody  it  is 
hardly  digested  at  all.  Hence  one  would  expect  the  constituents  of 
bran,  enclosed  as  they  are  by  woody  cellulose,  to  be  but  indifferently 
absorbed.  Experiment  fully  justifies  this  expectation.  Donders' 
observed  that  the  walls  of  bran  cells  were  digested  by  herbivora, 
but  not  by  man  ;  and  Giraud  was  able  to  demonstrate  the  aleurone 
cells  in  the  human  excreta  unchanged — an  observation  which  has 
been  more  recently  confirmed  by  Moeller.*  Pozziale,^  too,  found 
that  bran,  which  had  originally  contained  13  per  cent,  of  nitrogenous 
matter,  still  retained  fully  3^  per  cent,  after  traversing  successively 
the  digestive  apparatus  of  two  dogs  and  a  hen.  One  is  therefore 
not  surprised  to  learn  that  Rubner^  found  that  only  one-third  of  the 
nutriment  contained  in  bran  is  capable  of  being  made  use  of  by  the 
human  digestive  organs. 

*  Bull.  53,  United  States  Department  of  Agriculture,  Office  of  Experiment 
Stations,  p.  43. 

^  Lebbin,  Archiv  /.  Hygient,  1897,  xxviii.  212. 

*  Quoted  by  Meyer,  op.  cit. 

*  Zeit.  f.  Biolog.,  1897,  xxxv.  291.  This  writer  gives  an  exhaustive  summary 
of  the  results  of  previous  workers  upon  the  digestion  of  various  cells  as  tested  by 
microscopical  examination  of  the  stools. 

*  Quoted  by  Meyer,  op.  cit.  •  Znt.  /.  Biolog.,  1883,  xix.  45. 


ABSORPTION  OF  WHOLEMEAL  BREAD  211 

Seeing  that,  of  the  total  amount  of  mineral  matter  which  whole- 
meal bread  contains,  fully  65  per  cent,  belongs  to  the  bran,  one 
would  expect  the  mineral  constituents  of  such  bread  to  be  specially 
singled  out  for  defective  absorption.^  And  this  is  so.  Fully  half 
of  them  never  enter  the  blood  at  all  (Rubner,  Goodfellow,  and 
others).  The  carbohydrates,  too,  of  wholemeal  bread  are  not  so 
completely  absorbed  as  those  of  white  bread,  more  than  5  per  cent, 
being  lost.^  Some  observers,  indeed,  have  found  a  greater  diflference 
between  the  absorption  of  wholemeal  and  white  bread  in  respect  of 
this  constituent  than  in  regard  to  any  other. 

The  results  of  observations  on  the  absorption  of  the  proteins  of 
wholemeal  bread  are  by  no  means  unanimous.  Some  experimenters 
{e.g.,  Goodfellow)  have  found  but  little  difference  between  the 
behaviour  of  wholemeal  and  white  bread  in  this  respect,  while 
others  (e.g.,  Meyer),  comparing  whole  wheat  bread  with  moderately 
fine  rye  bread,  have  found  a  difference  of  10  per  cent,  or  more  in 
favour  of  the  latter. 

Some  of  the  most  conclusive  experiments  on  this  point  may  be 
cited  here.  Rubner'  compared  the  relative  absorption  of  bread 
made  from  the  three  following  flours:  (i)  Finest  white  flour 
('  patents  ')  ;  (2)  middle  quality  ('  seconds ') ;  (3)  '  wheatmeal  flour.' 

In  making  the  loaves,  the  directions  of  the  Bread  Reform  League 

were  followed.     Upwards  of  600  grammes  of  the  bread  were  eaten 

daily,  the  amount  of  nutrients  contained  in  each  case  being  as  follows : 

....  c.  Carbo-  Mineral 

Nttrogen.  Fat.  ^^,^^^^^^_  3^^^^^^_ 

No.  I.      1020  669  5288  239 

..    a.      1319  565  5079  285 

..    3'      1245  12-65  5045  854 

Bread  No.  i  contained  68-5  per  cent,  water ;  No.  2  had  69*4  per 
cent.  ;  No.  3,  62*4  per  cent.  The  percentages  of  loss  from  non- 
absorption  were  these : 


Quantity 

Percent. 

Percent. 

Bc««d. 

of  Dry 

Dry 

Percent. 

Percent. 

Carbo- 

Percent. 

Substance 

Substance 

N  lost. 

Fat  lost. 

hydrate 

Ash  lost. 

eaten. 

lost. 

lost. 

No.  I. 

6153  grammes 

403 

20-07 

44  69 

i-io 

19-28 

II      2- 

6126 

6-66 

24-36 

62-83 

257 

3035 

..    3- 

6171         „ 

12-23 

3047 

5114 

737 

4498 

*  There  is  some  reason  to  believe,  ho-vvever,  that  -wholemeal  bread  is  capable  of 
yielding  a  larger  amount  of  iron  to  the  body  that  white  bread.  (See  United 
States  Department  of  Agriculture,  Bulletin  185.) 

'  Moeller,  however  {Zeit.f.  Biolog.,  1897,  xxxv.  291),  states  that  he  could  find  no 
starch  cells  in  the  fasces,  even  -when  Graham  bread  w-as  eaten.  Notwithstanding 
this,  he  decides  the  question  of  wholemeal  versus  white  bread  entirely  in  favour 
of  the  latter. 

»  Zfit.  f.  Biolog.,  1883,  xix.  45. 


212  FOOD  AND  DIETETICS 

The  absolute  losses  were : 

F^^el  ^"^-  N.  Fat  ,Ca^^^;^  Ari. 

No.  I.       132  7  24-8  217  299  5  83  a-39 

„    2.      2528  408  324  355  1310  390 

..     3-       3178  757  380  647  3723  834 

He  draws  special  attention  to  the  great  absolute  loss  of  carbo- 
hydrate in  the  wholemeal  bread. 

Other  experiments  have  been  made  in  America, *  in  which 
the  absorption  of  bread  made  from  '  patents  '  and  '  baiters' '  flour 
respectively  was  studied,  672  grammes  (24  ounces)  of  bread  being 
taken  daily.     The  results  were : 

Pbr  Cent.  Digested. 


B'-d-  u:.L.         P-'""-  F>-  hj^^at.. 


'rotein. 

Fat. 

91 'O 

946 

905 

947 

•Bakers'' 942  9i'o  946  96-8 

'Patents' 944  905  947  969 

No  difference  was  found  in  this  case  between  the  two  kinds  of  bread. 
In  another  set  of  experiments, ^  white  bread,  entire  wheat,  and 
Graham  bread  were  compared,  with  the  following  results: 

100  Grammes  or  Bread  yield  in  the  Body. 


Calorits. 

Protein. 

White  bread 

•  • 

,.     269 

86  grammes. 

Entire  wheat  bread 

•  • 

..     235 

8-6 

Graham  bread     . . 

.. 

..     218 

8-3        .. 

Taking  the  results  as  a  whole,  it  may  fairly  be  concluded  that  the 
protein  of  wholemeal  bread  is  not  so  well  absorbed  as  that  of  white 
bread.  Even  bread  made  from  decorticated  wheat  does  not  offer  the 
advantages  often  ascribed  to  it,  for  exact  experiment  has  shown  that 
it  is  not  much  better  absorbed  than  ordinary  wholemeal  bread.' 

The  defective  absorption  of  wholemeal  bread  is  no  doubt  to  be 
attributed  to  the  large  amount  of  cellulose  which  it  contains.  The 
cellulose  acts  chiefly  by  preventing  the  access  of  the  digestive  juices 
to  the  nutritive  ingredients  which  are  enclosed  in  it.  It  is  also 
sometimes  said  to  interfere  with  absorption  by  hurrying  on  the 
contents  of  the  intestine  by  the  stimulating  influence  which  it  exerts 
on  peristalsis.  This  would  appear,  however,  to  be  an  error,  for 
Rubner  found*  that,  on  the  whole,  the  faeces  on  a  coarse  bread  diet 

'  United  States  Department  of  Agriculture,  Office  of  Experiment  Stations, 
Bulletins  67,  loi,  126. 

3  United  States  Department  of  Agriculture,  Farmers'  Bull.  112.  See  also 
Bulls.  85  and  loi.  Office  of  Experiment  Stations,  1900  and  igor,  p.  35,  1900,  of 
the  same  Department. 

3  Menicanti  and  Prausnitz,  '  Untersuchungen  iiber  das  Verhalten  verschiedener 
Brotarten  im  Menschlichen  Organismus"  (Zeit. /.  Bwlog.,  iSg^,  xxx.  3281. 

«  Op.  ttl. 


COMPARATIVE  ABSORPTION   OF  BREADS        71$ 

were  more  slowly  evacuated  than  those  of  fine  bread.  On  the  other 
hand,  the  residue  of  wholemeal  bread  seems  more  prone  to  undergo 
fermentation,  with  the  production  of  acids,  and  it  is  to  this  that  the 
greater  wateriness  of  the  wholemeal  bread  faeces  is  to  be  attributed, 
for  the  intestine  endeavours  to  neutralize  the  acids  by  a  greater  flow 
of  alkaline  fluid.  It  is  probably  for  this  reason  that  wholemeal 
bread  interferes  somewhat  with  the  absorption  of  other  foods. 
Thus,  Goodfellow^  has  found  that  the  waste  in  milk  is  greater  by 
3  per  cent,  when  given  along  with  wholemeal  bread  than  when 
taken  alone.  This,  as  we  have  seen,  is  the  very  reverse  of  the 
effect  exercised  by  ordinary  bread. 

Taking  the  mean  results  of  available  experiments,  one  may  con- 
trast the  absorption  of  the  constituents  of  white  and  wholemeal  bread 
thus :  » 


WhiU  Bread. 

Bread. 

Total  solids 

•  • 

•.       4^  per  cent. 

14            per  cent." 

1 

Proteins 

•  • 

..      20             „ 

20  to  30        „ 

Vlost 

Ash   .. 

•  • 

..     25 

51 

Carbohydrates 

.. 

..       3 

6 

1 

These  results,  which  were  all  obtained  from  observations  on 
healthy  human  beings,  are  entirely  confirmed  by  experiments  on  the 
digestibility  of  bread  in  the  laboratory  by  means  of  artificial  juices. 
By  this  method  Brunton  and  Tunnicliffe^  found  that  sugar  is  pro- 
duced much  more  rapidly  from  white  bread  than  from  brown,  and 
that  14  per  cent,  more  of  the  nitrogenous  matter  was  dissolved  in 
the  former  case  than  in  the  latter.  Goodfellow,'  by  a  very  similar 
method,  had  already  obtained  the  same  result. 

It  might  reasonably  be  contended  that  the  defective;,  absorption  of 
the  constituents  of  bran  is  due  to  imperfect  grinding,  and  that  if  the 
bran  were  reduced  to  as  fine  a  powder  as  the  flour  it  would  be  as 
well  digested  as  the  latter.  To  some  extent  this  is  true,  and  brown 
breads  made  from  finely  ground  patent  wholemeals  are  unques- 
tionably better  digested  than  the  ordinary  coarse  brown  bread. 
Obiervations  by  Romberg,*  however,  on  the  digestion  of  rye  bread, 
show  that,  no  matter  how  well  ground  the  bran  is,  it  is  never 
as  well  absorbed  as  the  flour.  He  prepared  a  series  of  breads 
from  rye,  the  meal  used  being  in  each  case  of  equal  fineness,  but 
differing  in  the  proportion  of  bran  contained.     Thus,  bread  No.  x 

'  '  Dietetic  Value  of  Bread, '  p.   199.     In  this  work  will  be  found  numerous 
experiments  on  the  absorption  of  wholemeal  bread. 
^  '  St.  Bartholomew's  Hospital  Reports,'  1897,  xxxiii.  157. 
»  'Dietetic  Value  of  Bread,"  pp.  183.  184. 
*  Romberg,  Archiv  f.  Hygiene,  1897,  xxviii.  244. 


Water.             Pro 

Jn  Dry  Substance. 

tein. 

Fat. 

Ash. 

Carbohydrate 

1. 

11-25          •         7 

•43 

009 

0-49 

91-09 

2. 

1 1  -84                 1 1 

•5Q 

I -14 

0-92 

86-35 

3- 

11-^6                 17 

•28 

2-13 

1-89 

78-70 

4- 

II  40                 16 

•84 

2-13 

2-22 

78-81 

D»7 
Substance. 

Protein. 

Ash. 

CarJo- 
hydrates,  etc. 

No.  I.           4-15 

22 -o 

58-8 

1-66 

»    2.           7-51 

28-6 

75-5 

4-15 

>i    3-         1304 

30"5 

74  "4 

8-o8 

„    4.         20-07 

43  "o 

61 '9 

14-40 

214  FOOD  AND  DIETETICS 

consisted  of  the  flour  only  and  was  perfectly  white,  while  No.  4  was 
made  from  the  whole  grain  and  was  very  dark ;  Nos.  2  and  3  were 
of  intermediate  quality.  The  following  tables  show  (i)  the  com- 
position of  the  meals  used ;  and  (2)  the  percentages  of  waste  in  the 
digestion  of  the  corresponding  breads: 

(X) 

No. 


(2) 


Seeing  that  the  ingredients  of  the  bread  were  in  an  equally  fine 
slate  of  division  in  every  case,  the  author  concludes  that  even  bran 
flotir  is  not  suitable  for  human  food,  and  that  no  method  of  preparing 
it  will  make  it  as  capable  of  being  absorbed  as  white  flour. 

Whether  finely -ground  wholemeal  bread  yields  more  mineral 
constituents  (especially  phosphates)  to  the  body  than  white  bread 
has  not  been  definitely  settled  by  experiments,  although  from  the 
observations  of  Rubner  already  cited,  the  absolute  yield  of  mineral 
matter  would  seem  to  be  greater  in  the  case  of  wholemeal  bread. 
Sherman  ^  states  that  the  body  probably  absorbs  from  a  pound  of 
genuine  whole-wheat  bread  at  least  twice  as  much  phosphorus, 
iron,  and  calcium  compounds  as  from  a  pound  of  white  bread. 
Seeing,  however,  that  an  ordinary  mixed  diet  always  contains  an 
excess  of  phosphates,  there  is  usually  nothing  to  be  gained  by 
increasing  the  amount  of  these  ingested.  In  any  case  a  large 
proportion  of  the  phosphates  in  ordinary  bread  are  present  in  organic 
combination,  and  are  therefore  more  available  for  nutrition  than  the 
mineral  phosphates  of  the  bran.  On  the  other  hand,  where  bread 
forms  the  chief  constituent  of  the  diet,  the  use  of  a  finely-ground 
wholemeal  bread  is  advantageous  from  the  mineral  point  of  view. 

The  absorption  of  wholemeal  bread  has  been  dwelt  upon  at  con- 
siderable length,  for  reasons  that  will  be  apparent  when  we  come  to 
consider  its  nutritive  value.  As  regards  the  digestibility  and 
absorption  of  bread  in  general,  it  only  remains  to  be  added  that 
there  is  some  reason  to  suppose  that  custom  plays  a  considerable 
part  in  it,  and  that  people  who  are  habitually  large  bread-eaters 

'Food  Products  '  (New  York  :  The  Macmillan  Co.,  1914),  p.  293, 


LACK  OF  PROTEIN  IN  BREAD  215 

acquire  the  power  of  digesting  it  more  completely  than  those  who 
are  not  so  habituated  to  its  use.^ 

NuTRiTiVB  Value  of  Bread. 

Weight  for  weight,  though  not  bulk  for  bulk,  bread  must  be 
regarded  as  one  of  the  most  nutritious  of  our  ordinary  foods.  This 
is  due  largely  to  the  fact  that  three-fifths  of  it  consist  of  solid 
nutriment,  and  but  two-fifths  of  water,  and  there  is  no  animal  food 
and  but  few  cooked  vegetable  foods  of  which  the  same  can  be  said. 

Of  the  chemical  constituents  necessary  for  proper  nutrition,  bread 
yields  to  the  blood  a  large  proportion  of  carbohydrates,  a  moderate 
amount  of  protein  and  mineral  matters,  but  almost  no  fat.  The  fact 
that  bread  is  usually  eaten  with  butter,  however,  renders  the 
absence  of  fat  a  consideration  of  but  little  importance. 

Yet  bread  cannot  be  regarded  as  a  perfect  food.     The  proportion 

of  protein  to  carbohydrate  is  too  low.     An  ideal  food  would  contain 

one  part  of  protein  to  4*2  parts  of  carbohydrate,  whereas  in  white 

bread  the  proportion  is  only  i  to  8^.     In  order  to  obtain  from  bread 

the  protein  requisite  in  an  ordinary  diet,  a  whole  4-pound  loaf  must 

be  eaten  every  day,  and  that  would  contain  more  than  twice  as  much 

carbohydrate  as  one  really  requires.     To  the  ordinary  mixed  feeder 

this  does  not  matter,  for  he  supplements  the  deficiency  of  protein  by 

adding  to  the  bread  a  '  protein-carrier '  such  as  meat,  m.ilk,  or  cheese. 

Where  bread  forms  the  staple  article  of  diet,  however,  as  it  does  in 

many  poor  households,  this  lack  of  protein  must  be  regarded  as  a 

serious  drawback.     Various  methods  of  overcoming  it  have  been 

tried,  all  of  which  consist  in  adding  to  the  flour  some  other  highly 

nitrogenous  substance.   Peasmeal  has  been  used  with  this  object,  and 

when  added  to  flour  in  equal  proportions  is  said  to  make  a  good  loaf. 

Skim  milk  has  also  been  employed.     A  loaf  made  entirely  with  skim 

milk  had  the  following  composition  when  compared  with  a  loaf  made 

from  the  same  flour  and  water  :^ 

Milk  Loaf.  Water  Loaf. 

Water           31-29  3259 

Protein          973  875 

Carbohydrate          ..         ..         ..  5666  5665 

Fat 0*96  0-86 

Ash    ..         ..       139  115 

Meat  has  also  been  proposed  as  an  addition,  2  pounds  of  flour 

1  See  Rubner,  Ztit.  f.  Biolog.,  1879,  xv.  154. 

2  Sartori,  quoted  by  Stutzer,  Weyl's  '  Handbuch  der  Hygiene,' iii.  251.  Some 
American  analyses  ('  The  Digestibility  and  Nutritive  Value  of  Bread,'  Bull.  85, 
United  States  Department  of  Agriculture,  Office  of  Experiment  Stations,  1900) 
also  showed  that  the  chief  difference  between  bread  made  with  skim  milk  and 
ordinary  bread  is  that  the  former  contains  i  per  cent  more  protein  in  the  fresh 
substance  than  the  latter. 


ai6  FOOD  AND  DIETETICS 

and  I  pound  of  cooked  minced  meat  making  a  good  and  digestible 
loaf,  which,  with  the  addition  of  fat,  is  almost  a  complete  food. 

More  elaborate  methods  are  by  the  addition  of  Aleuronat  or  of 
casein.  Aleuronat  was  introduced  by  Dr.  Hundhausen.  It  is 
simply  gluten  prepared  in  a  special  way,  and  contains  80  per  cent, 
of  protein.  It  is  a  colourless,  odourless  powder,  which  is  well 
digested  and  absorbed,  and  when  added  to  flour  in  the  proportion  of 
I  part  to  3  yields  a  loaf  containing  nearly  20  per  cent,  of  protein,  at 
a  cost  but  little  above  that  of  ordinary  bread.^  The  addition  of 
casein  is  employed  by  the  Protene  Company  in  their  household 
Protene  bread,  25  per  cent,  of  casein  being  added  to  ordinary  flour. 
The  resulting  loaf  is  very  rich  in  protein,  but,  owing  to  the  price  of 
casein,  is  necessarily  rather  expensive. 

It  must  be  admitted  that  none  of  these  methods  of  increasing  the 
amount  of  protein  in  bread  is  altogether  adapted  for  ordinary  use, 
and  that  they  are  all  apt  to  make  the  cost  of  the  bread  too  great. 
Perhaps  one  or  other  of  the  germ  breads  now  in  the  market,  of 
which  Hovis  is  the  best  example,  meets  the  requirements  better 
than  any  substitute  which  has  yet  been  proposed.  About  3  pounds 
of  such  a  bread  would  supply  all  the  protein  required  daily,  and 
would  only  contain  a  slight  excess  of  carbohydrate.  With  the  free 
addition  of  butter  or  some  other  fat,  it  is  not  far  from  being  a  com- 
plete food.  Unfortunately,  there  are  not  many  experiments  avail- 
able to  determine  whether  or  not  the  *  germ '  is  well  absorbed. 
Goodfellow^  has  given  some  attention  to  the  matter,  however,  in  the 
case  of  Hovis  bread,  and  found  that  the  loss  was  only  very  slightly 
above  that  of  ordinary  white  bread. 

Putting  aside  such  patent  breads,  it  may  be  said  that  white  bread 
made  from  '  seconds  '  flour  will  yield  more  nitrogen  to  the  body  than 
a  bread  made  of  ordinary  flour,  and  still  more  than  one  made  of 
'  patents.'    The  reasons  for  this  have  already  been  discussed  (p.  193). 

When  we  pass  on  to  consider  the  relative  nutritive  values  of 
white  and  wholemeal  bread,  we  are  on  ground  which  has  been  the 
scene  of  many  a  controversy.  It  is  often  contended  that  wholemeal 
is  preferable  to  white  bread,  because  it  is  richer  in  protein  and  mineral 
matter,  and  so  makes  a  better-balanced  diet.  But  our  examination 
of  the  chemical  composition  of  wholemeal  bread  has  shown  that,  as 
regards  protein  at  least,  this  is  not  always  true,  and  even  were  it  the 
case,  the  lesser  absorption  of  wholemeal  bread,  which  we  have  seen 
to  occur,  would  tend  to  annul  the  advantage.     As  regards  mineral 

*  Carl  Voit,  Archivf.  Hygi  ne,  1893,  xvii.  408. 

*  •  Dietetic  Value  of  Bread,'  p.  255. 


ECONOMIC  VALUE  OF  BREAD 


«i7 


matter  the  evidence  is  not  so  clear,  and  there  is  some  reason  to 
believe  that  the  absolute  yield  of  these  constituents  to  the  body  is 
greater  with  wholemeal  bread,  especially  if  it  be  finely  ground.  In 
the  case  of  an  individual  living  upon  an  ordinary  mixed  diet,  how- 
ever, this  advantage  is  not  a  matter  of  great  importance. 

Where  bread  constitutes  the  chief  source  of  nutriment,  as  is 
unfortunately  only  too  often  the  case,  it  is  probably  wisest  to  use 
the  old-fashioned  household  bread,  made  from  80  per  cent,  or 
so-called  '  standard '  flour,  which  is  not  brown  but  cream-coloured, 
and  which  includes  both  the  germ  and  semolina.  This  is  certainly 
superior  to  ordinary  white  bread  from  a  chemical  point  of  view, 
whilst  it  is  in  no  way  inferior  to  the  latter  in  digestibility  and 
capability  of  absorption.* 


Economic  Value  of  Bread. 

Bread  is  not  only  one  of  the  most  nutritious,  but  it  is  also 
amongst  the  cheapest  of  foods.  In  an  earlier  chapter  we  saw  that 
for  a  given  sum  one  obtains  a  larger  number  of  Calories  from 
bread  than  from  any  other  food.  As  regards  the  actual  amount  of 
dry  nutriment  obtained,  bread  also  heads  the  list.     Thus — 

A  pennyworth  of  bread      yields 
„  oatmeal 

„  lentils 

„  potatoes 

„  rice 

„  cheese 

„  carrots 

„  fish 

„  meat 

(Goodfellow.) 

Taking  protein  alone  as  the  standard,  it  is  found  that  bread  is  a 
fairly  cheap  source  even  of  that  constituent.     Thus — 


8    oz.  of 

dry 

nutriment 

7i         .. 

„ 

5h        .. 

, 

5i         .. 

, 

5i         .. 

, 

2i           » 

, 

2           „ 

, 

I           „ 

z  pound  of  protein  costs  in  the  form  of  maize 

beans 


oatmeal  .. 

flour  .. 

bread  . . 

cheese  . . 

rice 

milk 

beef/^^«^^P^^t 

eggs 


6d. 
7d 

I  Id. 
IS.  2d. 
IS.  3id. 
IS.  5d. 

2S.  2^d. 

IS.  4|d. 
4S.  5d. 
5s.  o^d. 


1  For  a  very  full  discussion  of  the  whole  subject,  the  concln-ions  of  which 
are  in  substantial  agreement  with  the  views  set  out  above,  see  Dr.  J.  M.  Hamill's 
'  Report  to  the  Local  Government  Board  on  the  Nutritive  Value  of  Bread  made 
from  Dififerent  Varieties  of  Wheat  Flour,'  1911.  A  paper  by  M.  Hindhede 
(■  Untersuchungen  iiber  die  Verdanlichkeit  Einiger  Brotsorten '  {Ziitsch.  /. 
Physik.  und  Didt.  Therapie,  xvii.  1913,  p.  68)  may  also  be  consulted. 


2i8  FOOD  AND  DIETETICS 

Of  the  patent  and  fancy  breads  as  a  whole,  it  may  be  said  that 
they  are  relatively  somewhat  dearer  than  white  bread.  About  i^d. 
per  pound  may  be  regarded  as  their  average  cost.  Even  ordinary 
brown  bread  has  ceased  to  be  cheaper  than  white,  and  cannot  there- 
fore be  recommended  on  that  ground. 

I  may  conclude  this  subject  in  the  words  of  Dr.  Goodfellow;! 
'  It  will  be  perfectly  clear  .  .  .  that  bread  is  one  of  the  cheapest 
foods,  not  only  with  regard  to  the  actual  weight  of  nourishment 
obtained,  but  also  with  regard  to  the  variety  of  the  nutrient 
constituents ;  and  the  purchaser  who  expends  his  modest  2^d. 
on  a  2-pound  loaf  may  rest  assured  that  he  could  not  spend 
his  money  to  better  advantage,  except,  perhaps,  in  the  purchase 
of  oatmeal,  which  contains  slightly  more  energizing  nutriment 
than  bread.' 

Bread  has  been  dwelt  upon  at  some  length  on  account  of  its  great 
practical  value.  The  other  food-stuffs  derived  from  wheat  may  be 
dismissed  more  briefly. 

Semolina  is  prepared  from  the  central  part  of  hard  wheats  which 
are  rich  in  gluten,  and  is  largely  used  in  the  South  of  Europe.  It 
contains  about  1 1  per  cent,  of  protein,  or  half  the  amount  contained 
in  an  equal  weight  of  beef.  It  must  thus  be  regarded  as  a  fairly 
nitrogenous  vegetable  food,  and  is  useful  for  making  puddings, 
porridge,  thickening  of  soups,  etc. 

Macaroni,  vermicelli  and  the  Italian  pastes  are  also  made  from 
flours  rich  in  gluten.  The  flour  is  made  into  a  paste  with  water, 
and  the  viscidity  of  the  gluten  then  allows  it  to  be  moulded  in 
various  ways  or  drawn  into  tubes.  It  is  afterwards  dried  or  slightly 
baked. 

Macaroni  and  vermicelli  absorb  about  three  times  their  weight  of 
water  in  the  process  of  cooking,  so  that  the  product  when  eaten, 
although  highly  nutritious,  is  about  eight  times  poorer  in  nitrogen 
than  a  similar  weight  of  beef. 

Macaroni  and  vermicelli  are  absorbed  almost  in  their  entirety.^ 
Their  use  is  therefore  indicated  in  conditions  where  it  is  ad- 
visable to  leave  behind  as  small  a  residue  as  possible  in  the 
intestine. 

The  following  table  represents  the  composition  of  these  and  some 
similar  preparations  from  analyses  by  Balland  : 


1  'Dietetic  Value  of  Bread,'  p.  io6. 
'  Rubner,  Zeit.  f.  Biolog.,  1879,  xv.  165. 


PATENT  PREPARATIONS  OF  WHEAT 


219 


COMPOSITION  OF  ITALIAN  PASTES.  Etc.* 


Water 

N 
Substances. 

10  98 

Fat. 

Starch, 
etc 

Cellu- 
lose. 

Ash 

Macaroni  (1895) 

1 1 '50 

045 

76-05 

028 

064 

..         (1897) 

12  DO 

1089 

0  65 

7570 

026 

0-50 

Vermicelli  (1896) 

10-90 

11-74 

050 

7574 

0-38 

0-74 

(1897)        .. 

1000 

12-51 

080 

7551 

028 

090 

pates  d'ltalie  (1897)   .. 

1040 

12  51 

080 

75  23 

0-30 

0  76 

Semolina  (1895) 

920 

13-50 

085 

75-45 

050 

0-50 

..        (1896) 

920 

10  42 

055 

7863 

045 

075 

..        (1897) 

10  50 

11-96 

0  60 

75  79 

0  50 

065 

Rice  semolina  (1898)  . . 

10  So 

734 

0  30 

80-96 

0-40 

020 

Foreign  tapioca  (1897) 

12  80 

0  00 

020 

86  88 

0-08 

004 

French   potato   tapioca 

(1897) 

16  00 

045 

0-15 

8295 

000 

045 

The  following  are  some  patent  preparations  of  wheat  : 

Granuto^  is  a  wheat  product  which  has  been  thoroughly  cooked 
and  subjected  to  the  action  of  malt  sufficiently  to  convert  a  consider- 
able proportion  of  its  starch  into  dextrin  and  maltose. 

Granola  is  a  whole-wheat  preparation  manufactured  by  Mr.  James 
Marshall  in  this  country.^  The  same  maker  produces  a  granular 
preparation  of  the  endosperm  of  wheat  under  the  name  of  Farola. 

Florador  is  another  wheat  product  of  recent  introduction,  and  in 
a  granular  form.  It  contains  io-6  of  protein  and  0*3  per  cent,  of 
mineral  matter,  and  is  recommended  for  use  in  the  making  of 
blancmange,  etc.  It  is  undoubtedly  far  more  nutritious  than  such 
preparations  as  cornflour,  which  are  so  commonly  used  for  a  similar 
purpose. 

The  composition  of  some  of  the  above  preparations,  when  cooked 
with  water  in  the  usual  way,  is  as  follows  :  * 


Semolina  .. 

Vermicelli  ..  .. 

Hominy  ..  ..  .. 

Farola  (fine  grain) 
,,       (medium  grain) 
,.      (large  gra-n)     .. 

Florador 

Granola  . .  . .  . . 


Water. 


9017 
87-14 
86-63 
90- 24 

8915 
86 -08 
89-45 
6740 


Protein. 


I  93 
2-44 

2-8i 

1-84 
1-91 
2-39 

I -So 
2-52 


Fat. 


008 
001 
009 
002 
001 
001 
001 
003 


Starch. 


7'25 
1082 
987 
783 
8-89 
1 1  06 
8-67 
9-42 


Cellulose. 


004 
007 
0"l6 
O  06 
006 

0-I5 
ooa 
o-io 


Mineral 
Matter. 


013 
0-I3 
002 
o  06 
0-14 
007 
o  10 

018 


^  Balland, /oMJ-n.  de  Pharm.  ef  de  Chim.,  1898,  S"*  s^r,,  vii.  328  ;  Analyst,  1898, 
p.  178. 

"^  Battle  Creek  Sanitarium  Company,  Ltd.,  Michigan,  U.S.A.  Several  other 
Ingenious  and  useful  cereal  preparations  are  made  by  this  company. 

*  25,  East  Cumberland  Street,  Glasgow. 

*  Analyses  by  Katherine  I.  Williams  C/oww.  Amer.  Cktm.  See.,  1907,  xxix., 
No.  4). 


220  FOOD  AND  DIETETICS 

Shredded  wlieat  is  a  preparation  of  whole  wheat  in  the  form  of 
shreds  or  flakes,  which  have  been  cooked  to  the  consistence  of  a 
biscuit,  and  represents  the  whole  grain  in  a  very  digestible  form. 
Chapman's  whole  wheat  flour  is  described  at  p.  469. 

Force  consists  of  malted  whole  wheat  in  the  form  of  flakes,  cooked 
with  steam.  It  is  easily  digested,  but  not  really  of  higher  nutritive 
value  than  fine  wheaten  biscuits  (see  p.  207).  The  following  is  its 
composition  : 

Water 928  per  cent. 

Protein     ..  ..  ,.  ..  ..  942       ,, 

Soluble  carbohydrates . .         ..         ..  11  36      ,, 

Insoluble  ,,  6569      „ 

Fat  135       „ 

Mineral  matter 290      „ 

Grape-Nuts  is  another  malted  preparation  of  the  entire  wheat 
berry,  which  requires  no  cooking.  It  contains  a  high  proportion  of 
soluble  carbohydrates,  as  well  as  a  considerable  amount  of  protein, 
as  is  shown  by  the  following  analysis : 

Water 618  per  cent. 

Protein     ..  ..  ..  ..  ..  1197        ,, 

Soluble  carbohydrates 4272        ,, 

Insoluble  ,,  ..         ..         ..  3652       „ 

Fat  061        „ 

Mineral  matter  ..         ..         ..         ..  200        ,, 

Bohorat  and  Glidine  are  protein  preparations  derived  from 
wheat.  In  addition,  they  contain  an  appreciable  amount  of 
lecithin.  As  they  are  practically  free  from  starch  they  are  useful 
aids  in  the  preparation  of  diabetic  foods,  and  may  be  regarded 
as  having  much  the  same  nutritive  value  and  uses  in  the 
diet  as  casein  preparations. 


Other   Cereals  :   Oats. 

Oats  may  be  regarded  as  the  most  nutritious  of  all  cereals.  They 
are  rich  in  nitrogenous  matter  and  mineral  substances,  and  are 
peculiarly  rich  in  fat,  the  only  other  cereal  which  can  at  all 
compare  with  them  in  that  respect  being  maize.  Starch  is  present 
to  the  extent  of  about  38  per  cent.  Further,  of  the  total  nitrogenous 
matter,  94  per  cent,  is  in  the  form  of  protein,  and  therefore  available 
for  tissse  -  building.  Unfortunately,  the  husk  of  oats  is  closely 
adherent,  and  cannot  be  entirely  separated  from  the  kernel,  so  that 


OATS  221 

by  the  ordinary  methods  of  grinding  a  good  deal  of  cellulose  is  left 
in  the  meal  in  the  form  of  small  sharp  particles.  These  act  as 
stimulants  to  the  intestine,  and  make  oatmeal  a  valuable  food  where 
the  intestinal  movements  are  sluggish,  but,  on  the  other  hand,  are 
apt  to  prove  rather  irritating  to  some  persons. 

Oatmeal  is  also  found  to  be  a  '  heating '  food  in  the  case  of  some 
individuals,  and  the  development  of  skin  eruptions  sometimes  follows 
its  use.  This  *  heating '  effect  is  said  not  to  be  due  to  the  large  amount 
of  protein  which  it  contains,  but  to  a  special  constituent  to  which  the 
name  '  avenin  '  has  been  given. ^  Similar  '  stimulating '  results  are 
often  observed  in  horses  which  are  liberally  supplied  with  oats.  It 
must  be  stated,  however,  that  the  existence  of  this  substance  is 
denied  by  many  observers.  Oatmeal  is  also  one  of  the  few  vegetable 
foods  which  contain  appreciable  quantities  of  uric-acid  formers 
(purin  bodies).  It  is  therefore  well  to  forbid  its  use  in  some  cases 
of  gout.  There  are  various  ways  of  preparing  oats  for  human  food. 
It  may  be  simply  cleaned  and  ground,  the  result  being  oatmeal  of 
various  degrees  of  fineness,  or  the  branny  particles  may  be  separated, 
and  the  '  oat  flour '  alone  used.  Groats  consist  of  oats  from  which 
the  husk  has  been  entirely  removed ;  when  crushed,  Embden  groats 
results. 

Eolling  has  recently  begun  to  be  employed  as  a  method  of  pre- 
paring oats,  instead  of  grinding.  The  great  pressure  to  which  the 
grains  are  subjected  between  the  rollers  ruptures  the  cell  walls, 
breaks  down  the  cellulose,  and  flattens  the  grains  out  so  that  they 
are  more  easily  softened  by  cooking.  By  the  application  of  heat 
during  the  rolling  process,  the  grains  are  at  the  same  time  partially 
cooked.  This  not  only  has  the  advantage  of  rendering  subsequent 
preparation  for  the  table  considerably  less  laborious,  but  also  alters 
the  fat,  which  is  so  abundantly  present  in  oats,  in  such  a  way  that 
it  is  less  liable  to  become  rancid,  so  preserving  the  natural  flavour 
of  the  grain. 

'  Quaker  Oats '  is  one  of  the  best  known  of  these  preparations. 
'  Waverley  Oats,'  '  Provost  Oats,'  Carr's  '  Oaten,'  'Creamota,'  and 
Montgomerie's  '  Berina'  are  examples  of  Scottish  rolled  oats. 
'  Avenine '  is  a  similar  product.  The  composition  of  some  special 
preparations  of  oats  is  shown  in  the  following  table  : 

*  Sanson,  Comptes  Renins,  1883,  icvi.  75. 


222 


FOOD  AND  DIETETICS 


PREPARATIONS  OF  OATS. 


Scottish 
Oatmeal. 

Irish 
Oatmeal. 

'  Quaker 
Oats." 

Carter's 
Oats. 

'  H-C 

Mont- 
gomerie's 

Fine 
Oatmeal. 

Scott's 

Oat 
Flour. 

Robin- 
son's 
Groats. 

Water  . . 

50 

50 

7-8 

31 

90 

6-3 

5-8 

104 

Protein 

146 

134 

147 

129 

I3« 

no 

100 

II  3 

Fat       .. 

101 

8-8 

6-2 

6-2 

8-3 

6-8 

50 

6-5 

Carbo- 

651 

684^ 

hydrates 

698 

760 

672 

742 

779 

704 

Cellulose 

31 

17) 

Mineral 

matter 

2-1 

20 

15 

1-8 

17 

17 

i'3 

17 

The   composition   of  some  of   these,   when   prepared   ready  for 
eating,  is  as  follows  : 

COMPOSITION  OF  ROLLED  OATS  WHEN  COOKED. » 


Water. 

Protein. 

Fat. 

Starch. 

Cellulose. 

Mineral 

Matter. 

Quaker  Oats      .. 
Provost  Oats     . . 
Mother's  Oats  .. 

9248 

88-44 
8972 

1-65 
200 
192 

032 
036 
045 

624 
900 
870 

009 
016 
015 

0  24 
0  24 
018 

It  will  be  observed  that  the  finer  the  product  the  poorer  it  is  in 
nitrogenous  and  mineral  matters.  In  this  respect  oat  flour  bears 
the  same  relation  to  oatmeal  as  fine  wheat  flour  does  to  whole 
wheatmeal.  2 

Veda  Oatmeal 3  is  a  special  preparation  of  oats  in  which  much  of 
the  starch  has  been  converted  into  soluble  forms.  It  is  thus  more 
easily  digested  than  ordinary  oatmeal,  and  may  agree  with  patients 
in  whom  the  latter  causes  acidity.  Plasmon  Oatmeal  is  a  combina- 
tion of  plasmon  and  oatmeal,  which  contains  20  per  cent,  of  protein 
and  8  per  cent,  of  fat.  It  is  pre-cooked,  and  of  very  high  nutritive 
value. 

Owing  to  the  absence  of  gluten,  oatmeal  is  unfitted  for  bread- 
making,  and  is  usually  simply  mixed  with  water  and  made  into 
cakes.  By  mixing  fine  oatmeal  with  an  equal  quantity  of  wheat 
flour,  however,  a  fairly  good  loaf  can  be  obtained.  A  given  weight 
of  oatcake  (made  without  butter)  contains  rather  more  than  twice  as 

»  Analyses  by  Katherine  I.  Williams  (Jourti.  Amer.  Chem.  Soc,  1907,  xxix., 
No.  4). 

2  Cowan's  '  special  quality  '  of  Scotch  oat  flour  is  an  excellent  preparation  for 
the  makitig  of  gruels  and  as  a  food  for  children 

8  The  Veda  Food  Company,  25,  North  Bridge,  Edinburgh. 


OATS  223 

much   building   material  as  an  equal  quantity  of  bread,   and    has 
almost  twice  as  great  a  fuel  value. 

Oatmeal  requires  to  be  very  thoroughly  boiled  in  order  to  soften 
the  cellulose  which  it  contains.  '  Brose,'  which  is  made  by  merely 
stirring  oatmeal  into  boiling  water,  is  not  a  food  for  delicate  stomachs. 
As  regards  the  absorbability  of  oats,  experiments  show^  that  porridge 
made  from  rolled  oats,  even  if  taken  in  considerable  quantities,  is 
very  well  absorbed.  Roughly  speaking,  95  per  cent,  of  its  protein, 
93  per  cent,  of  its  fat,  and  96  per  cent,  of  its  carbohydrates  enter  the 
blood,  whilst  92  per  cent,  of  the  energy  which  it  contains  is  '  avail- 
able '  in  the  body.  This  compares  very  favourably  with  the  results 
yielded  by  bread.  On  purely  chemical  grounds,  oats  compare  very 
favourably  with  wheat  as  a  source  of  nutriment.  A  typical  tea  and 
bread-and-butter  meal  (No.  i)  may  be  contrasted  with  one  of  porridge 
and  milk  (No.  2)  of  the  same  cost  (lid.)  thus^: 

No.  I. 

Ingrediinti,  Protein.  Fat.  Carbohydrates. 

Tea —  —  _ 

Sugar  (^  ounce)      ..          ..       —  —  I4'2 

Milk  (i|  ounces)    ..          ..        1*2                       1-4  l'7 

Bread  (10  ounres)  . .          ..     26'i                       3*7  I50"8 

Butter  (J  ounce)    ..          ..       0-2  if^  — 

Total 275  i6-6  1667 

No.  2. 

Oatmeal  (8  ounces)           ..     36'6  16*4  f53'4 

Milk  (10  ounces)    ..         ..       9-4  II-3  14-2 

Total 460  277  167-6 

The  total  energy  value  of  the  first  meal  is  950-6  Calories  ;  of  the 
second,  1,133  Calories.  The  superiority  of  the  porridge  and  milk  meal 
as  a  source  both  of  building  material  and  of  energy  is  very  striking. 

Maize  (Indian  Corn).' 

Maize  is  not  so  largely  used  as  human  food  in  Great  Britain  as  it 
should  be,  but  throughout  America  it  forms  a  staple  article  of  diet, 
while  in  Mexico  and  Natal  maize  is  literally  the  '  staff  of  life ' 
(Letheby).  It  was  introduced  into  Ireland  at  the  time  of  the  potato 
famine  in  1848,  and  has  since  established  a  place  for  itself  in  the 

'  Bu!'°tin  No.  loi,  United  States  Department  of  Agriculture,  Office  of  Experi- 
ment Sia..ions,  p.  47,  1901. 

*  •  A  Study  of  the  Diet  of  the  Labouring  Classes  in  Edinburgh,'  p.  77  (Edin- 
burgh :  Otto  Schulze  and  Co.). 

*  For  much  practical  information  on  the  use  of  maize  as  a  fo-^d,  see  United 
States  Department  of  Agriculture's  Farmers'  Bulletins,  Nos.  559  and  565  (1913 
and  1914). 


224  FOOD  AND  DIETETICS 

dietary  of  the  people,  so  that  Ireland  now  imports  more  of  it  for 
food  purposes  than  any  other  European  country. 

Chemical  analysis  (see  Table,  p.  i88)  shows  that  maize  is  quite  as 
nutritious  as  wheat  in  all  except  its  mineral  ingredients,  while  it  is 
richer  in  fat  than  any  cereal  except  oats,  containing  twice  as  much 
of  this  important  constituent  as  wheat  or  barley,  and  three  times  as 
much  as  rye.  In  nitrogenous  matter  it  is  slightly  inferior  to  most 
other  cereals,  but  fully  87  per  cent,  of  this  is  in  a  protein  form.  As 
regards  its  digestible  carbohydrates,  it  is  equal  to  wheat,  but  some- 
what inferior  to  barley  or  rye. 

Maize  is  prepared  for  food  in  many  different  ways.     In  Ireland  it 

is   made  into  a  sort  of  porridge,  called  stirabout,  or,  in  the  more 

expressive  phraseology  of  America,  mush.     In  Northern  Italy  and 

the   South    Tyrol  it  is  prepared   in    a   similar   way,   but  with  the 

addition  of  cheese  and  other  ingredients.     Maizemeal  is  prepared 

by  grinding  after  removal  of  the  germ  and  husk.     A  yellow  and 

a  white  meal  are  thus  prepared,  but  there  is  no  difference  between 

them  as  far  as  nutritive  value  is  concerned.       Fine  maizemeal  is 

more  gritty  than  wheat  flour,  but  when  mixed  with  the  latter  its 

presence  can  hardly  be  detected.      The  comparative  cheapness  of 

maize  flour  is  an  inducement  to  millers  to  adulterate  wheat  flour 

with  it,  and  this  is  already  being  done  to  some  extent  in  America 

and  France.     Flour  so  adulterated  yields  fewer  loaves  than  an  equal 

quantity  of  pure  wheat  flour,  and  the  bread  produced  is  moister  than 

wheaten  bread,  and  has  a  tendency  to  be  sodden.     An  addition  of 

10  per  cent,  of  maize  flour  is  calculated  to  mean  a  reduction  of  five 

loaves  on  the  sack.     Owing  to  the  absence  of  gluten,  this  meal  cannot 

be  used  to  make  ordinary  bread,  but  it  is  often  baked  into  cakes  of 

various  sorts.     The  johnny  (corruption  of  '  journey  ')  cakes  of  North 

America  are  unleavened,  and  are  made  of  a  rather  coarse  maizemeal. 

Similar  cakes  constitute  the  tortilla  of  South  America.    The  following 

is  the  composition  of  johnny  cakes  :^ 

Water        380  percent 

Protein 85         „ 

Fat *  27        „ 

Carbohydrates 47*3        ,, 

Mineral  matter    ..         ..         ..         ..  3'5         ,, 

On  comparing  this  with  the  analysis  of  good  white  bread,  given  on 
p.  202,  it  will  be  seen  that  the  comparison  is  all  in  favour  of  maize. 
Sometimes  the  maizemeal  is  leavened  with  yeast  and  subsequently 
baked  in  iron  vessels.  In  this  form  it  is  known  as  pone,  while  in 
Ireland  baking-powder  is  used,  or  the  maizemeal  is  mixed  with  flour 
and  then  converted  into  loaves.  One-third  of  its  weight  of  good 
^  Analysis  by  Atwater  and  Wood. 


MAIZE  225 

flour  is  sufficient  to  enable  fine  maizemeal  to  form  good  loaves. 
The  colour  of  the  bread  is  always  rather  dark,  however,  even  if  the 
proportion  of  wheat  flour  used  be  increased  to  one-half. 

Various  special  preparations  of  maize  deserve  mention.  Hotnvty, 
cerealine  and  samp  are  preparations  of  broken  or  split  maize  of 
various  degrees  of  fineness.  The  composition  of  the  first  two  is 
as  follows : 

Hominy.^  Cerealine!* 

Water        ..         ..         ..         ..     iig  per  cent.  10 -6  per  cent. 

Protein 82        ,,  94       ,, 

Fat  ..         ..         ..         ..       06        „  10      „ 

Carbohydrates     ..         ..         ..     789        ,,  786      „ 

Mineral  matter    ..  ..  ..       04        „  0*4       „ 

Both  preparations  are  of  high  nutritive  value  and  admirably  adapted 
for  making  puddings,  etc. 

Cornflour,  maizena  and  oswego  are  prepared  from  maize  by  washing 
away  the  protein  and  fat  by  means  of  dilute  alkaline  solutions,  so 
that  little  but  starch  is  left.  Church  states  that  cornflour  contains 
only  18  grains  of  protein  in  every  pound,  and  a  sample  of  Brown 
and  Pokon's  cornflour  which  the  writer  examined  showed  a  mere 
trace  of  nitrogen.     The  following  is  an  analysis  of  maizena  ;' 

Water         ..  ..  ..  ..  .,  i4"3  percent. 

Protein      . .  . .  . .  . .  . .  o'5        „ 

Carbohydrates  ..  ..  ,.  ..  849        „ 

Mineral  matter  ..  ..  ..  ..  03        „ 

These  preparations  must  therefore  be  regarded  simpl"  as  agreeable 
forms  of  starch,  well  adapted  for  food,  provided  they  are  taken  along 
with  some  protein  and  fat  carrier,  such  as  eggs  or  milk,  but  by  no 
means  to  be  recommended  on  economic  grounds. 

A  special  small  variety  of  maize  is  called  in  America  pop-corn. 
When  roasted  it  swells  up  and  ultimately  bursts.  In  this  form  it  is 
known  as  '  popped  pop-corn,'  and  is  the  basis  of  various  sweets. 
Its  composition  is  as  follows  :* 

Pop-corn  Pop-corn 

{Raw).  {Popped). 

Water     ..         ..         ..         ..     io-8  percent.  4'3  percent. 

Protein 11-2        „  107        „ 

Fat 52        „  50        „ 

Carbohydrates 71-4        „  787        „ 

Mineral  matter  ..         ,,1-4        „  1*3        „ 

It  is  thus  a  valuable  food. 

Com  Flakes^  consist  of  cooked  maize  which  has  been  treated  with 
malt-honey,  dried,  rolled  and  baked.  It  is  a  nutritious  and  digestible 
breakfast  food. 

*  Analysis  by  the  author. 

*  Analysis  by  Atwater  and  Wood. 

*  Given  by  Klemperer  in  Leyden's  '  Handbncb  der  Ernahrungstberapie,'  p.  298. 

*  Analysis  by  Atwater  and  Wood. 

*  Battle  Creek  Sanitarium  Company,  Ltd. 

'5 


226  FOOD  AND  DIETETICS 

Sugar-corn  is  a  special  variety  of  maize,  containing  much  sugar. 
It  is  cooked  while  still  green,  and  forms  a  sweet  and  succulent 
vegetable  much  esteemed  in  America. 

Maize  is  not  only  a  highly  nutritive  cereal  from  the  chemist's 
point  of  view,  but  has  the  further  advantage  of  being  very  well 
digested  in  the  human  body.  Experiments  show  that  90  per  cent, 
of  its  dry  matter  is  absorbed,  as  compared  with  82  per  cent,  in  the 
case  of  wheat.  Of  the  protein  of  maize,  19-2  per  cent,  escapes 
absorption  ;^  in  wheat  about  20  per  cent,  is  lost. 

Maize  must  undoubtedly  be  regarded  as  a  food  of  great  nutritive 
value.  '  With  a  diet  of  Indian  corn  bread  and  pork,'  says  an  American 
writer,^  '  the  workmen  of  this  country  are  capable  of  enduring  the 
greatest  fatigue  and  performing  the  greatest  amount  of  physical 
labour.' 

It  is  also  an  economical  food.  It  has  been  calculated^  that  when 
maize  and  wheat  are  both  selling  at  the  same  price  per  bushel  one 
gets  the  same  amount  of  digestible  matter  for  a  given  sum  in  both. 
In  wheat,  however,  one  gets  2J  pounds  more  protein,  and  in  maize 
■2\  pounds  more  carbohydrate.  The  fuel  value  in  each  case  is  almost 
precisely  the  same. 

In  view  of  these  facts  and  of  the  approaching  scarcity  of  wheat, 
one  cannot  help  a  feeling  of  regret  that  maize  is  not  more  widely 
adopted  as  a  food  amongst  the  working  classes  of  this  country.  '  The 
cry  of  Europe,'  says  C.  J.  Murphy,*  *  is  "  cheap  bread  " ;  it  is  a  bitter, 
agonizing  cry,  and  we  may  best  respond  to  it  by  instructing  the 
toiling  masses  of  the  Old  World  in  the  excellence  and  cheapness  of 
maize,  and  the  proper  methods  of  preparing  it.' 

Barley. 

Barley  is  chiefly  characterized  by  its  richness  in  mineral  matter. 
It  contains  more  fat  than  wheat,  but  is  comparatively  poor  in 
protein.  The  amount  of  starch  in  it  varies  in  diflferent  samples  from 
39  to  57  per  cent.  (O'SuUivan).  The  whole  grain  when  ground 
constitutes  barleymeal.     Scotch  barley  is  the  grain  stripped  of  its 

1  Rubner,  Znt.  /.  Biolog.,  1879,  xv.  115.  See  also  experiments  by  Malfatti, 
quoted  by  Konig. 

"  United  States  Bepartment  of  Agriculture,  Division  of  Chemistry,  Bulletin  50, 
p.  II. 

*  Ibid.,  p.  14. 

*  '  Report  to  United  States  Department  of  A£[riculture  on  the  Use  of  Maize  in 
Europe,'  p.  6. 


BARLEY  ttj 

husk   and   roughly   ground.      It   is  chiefly   used   as   human   food, 

however,  in  the  form  of  either  '  pearl '  or  *  patent '  barley.     The 

former  consists  of  the  whole  grain  polished  after  removal  of  the 

husk  ;  the   latter  is   simply  pearl   barley  ground   into  flour.     The 

composition  of  these  preparations  is  shown  in  the  Table  (p.  i8g), 

and  the  following  is  an  analysis  of  Robinson's  Patent   Barley  by 

Leeds : 

Moisture  loio  per  cent. 

Protein 5"i3        m 

Fat        0-97        „ 

Carbohydrates  ..  ..  ..  ••  81-87         »• 

Mineral  matter  i*93         >i 

Barley  contains  but  little  gluten,  in  consequence  of  which  its 
dough  is  too  '  heavy '  to  make  good  bread.  When  mixed  with  half 
its  weight  of  good  wheat  flour,  however,  barleymeal  can  be  con- 
verted into  good  enough  loaves. 

Writing  on  the  nutritive  value  of  barley  in  1872,  Letheby  said: 
*  Barleymeal  is  the  chief  food  of  a  large  number  of  people  in  the 
North  of  Europe  and  in  the  South  of  England,  where  the  labourer  is 
partly  paid  his  wages  in  meal  or  grain.  It  is  also  used  in  Wales 
and  Scotland,  especially  in  winter-time,  when  wheaten  bread  is  dear, 
and  to  some  extent  in  Ireland.  It  is  employed  by  about  90  per  cent. 
of  the  out-door  labouring  population  of  England.  At  the  time  of 
Charles  I.  (1626),  according  to  M'Culloch,  it  was  the  usual  food  of 
the  ordinary  sort  of  people,  and  as  late  as  the  middle  of  the  last 
century  hardly  any  wheat  was  used  in  the  Northern  counties  of 
England.  In  Cumberland  the  principal  families  used  only  a  small 
quantity  of  wheaten  bread  about  Christmas-time.  The  crust  of  the 
everlasting  goose-pie,  which  adorned  the  table  of  every  county 
family,  was  invariably  made  of  barleymeal.' 

Since  this  was  written  barley  has  been  steadily  more  and  more 
displaced  by  wheat  as  an  ordinary  article  of  diet,  and  no  doubt  with 
considerable  nutritive  advantage. 

As  an  article  of  diet  in  the  sick-room,  barley  finds  its  chief  use  as 
the  main  ingredient  of  barley-water,  a  preparation  which  contains, 
however,  but   very  little   nutriment,  as  the   following  analysis   by 

Wynter  Blyth  shows  :^ 

» 

^  A  series  of  analyses  by  Corlette  {Australasian  Med.  Gazette,  1905,  xxiv.  i  ) 
of  barley-^vater  prepared  from  two  heaped  teaspoonfuls  of  pearl  barley  to  a  pint 
of  water  showed  that  the  average  amount  of  starch  in  the  product  amounted 
to  2  03  per  cent. 


aa8  FOOD  AND  DIETETICS 

Water 99*27  per  cent. 

Fat  002 

Protein ..         ..  003        ,, 

Stared 0*39 

Sugar 0*05        ,, 

Mineral  matter  ..  o'o3        ,, 

It  is  chiefly  of  value  on  account  of  its  demulcent  properties. 

Rye. 

Next  to  wheat,  rye  is  the  great  bread-making  grain  of  the 
world.  It  contains  less  gluten  than  wheat,  and  the  kind  of 
gluten  seems  to  be  also  chemically  different,  and  as  a  result  of  this 
the  bread  derived  from  rye  is  apt  to  be  rather  moist  and  dense. 
An  extreme  example  is  the  black  bread,  or  pumpernickel,  of  North 
Germany. 

The  composition  of  the  different  flours  derived  from  rye  varies 
very  considerably  with  the  fineness  of  milling ;  but  fine  rye  flour  is 
much  poorer  in  protein  than  flour  of  a  similar  grade  produced  from 
wheat.i 

Fine  rye  bread  is  therefore  poorer  in  building  material  than 
wheaten  bread,  but  it  is  somewhat  superior  in  this  respect  to  bread 
made  from  maize. 

The  digestibility  of  fine  rye  bread  is  about  equal  to  that  of  good 
wheaten  bread ;  but  the  coarser  varieties,  especially  pumpernickel, 
are  very  wasteful  foods,  32  per  cent,  of  the  protein  even  in 
moderately  fine  rye  bread  being  lost,  as  compared  with  20  per  cent. 
in  white  bread.  In  the  case  of  pumpernickel  the  loss  rises  to  42  per 
cent. 

RiCB. 

Rice  is  the  poorest  of  all  cereals  in  protein,  fat  and  mineral  matter. 
On  the  other  hand,  it  has  fully  76  per  cent,  of  starch.  The  starch 
has  the  further  advantage  of  being  present  in  small  and  easily- 
digested  grains.  When  boiled,  rice  swells  up  and  absorbs  nearly 
five  times  its  weight  of  water,  while  some  of  its  mineral  constituents 
are  lost  by  solution.  It  is  preferable,  therefore,  to  cook  it  by  steam- 
ing.    Boiled  rice  has  the  following  composition  i^ 

Water 527  percent. 

Protein 5*0        „ 

Fat  ..         ..         ..         ..         ..         ..       o'l        „ 

Carbohydrates  419        „ 

Mineral  matter  . .         . .         . .         . .       0*3        „ 

*  Vide  Faike,  Archiv /.  Hygiene,  1897,  xxviii.  49,  and  Romberg,  ibid.,  1897,  xxviii 

«44- 

*  Analysis  by  Atwater  and  Woods, 


RICE  229 

Rice  is  only  moderately  easy  of  digestion  in  the  stomach,  2|  ounces 
cooked  by  boiling  {i.e.,  about  two-thirds  of  a  full  soup-plateful) 
requiring  three  and  a  half  hours  for  its  disposal.  This  is  probably 
to  be  attributed  to  the  fact  that  it  is  not  the  function  of  the  stomach 
to  digest  carbohydrates. 

On  the  other  hand,  rice  is  absorbed  with  very  great  completeness 
in  the  intestine ;  indeed,  its  solid  constituents  enter  the  blood  almost 
as  completely  as  those  of  meat.  This  is  to  be  attributed  to  the 
comparative  absence  of  cellulose.  Practically  none  of  the  starch  is 
lost,  but  the  waste  of  protein  amounts  to  19  per  cent.^  It  follows 
from  this  that  rice  is  one  of  the  foods  which  leave  the  smallest 
residue  in  the  intestine,  and  this  gives  it  a  considerable  value  in 
some  cases  of  disease. 

The  nutritive  value  of  rice  is  much  impaired  by  its  poverty  in 
protein  and  fat.  Hence  it  is  not  adapted  to  be  an  exclusive  diet, 
but  should  be  eaten  along  with  other  substances  rich  in  these  two 
elements,  such  as  eggs,  cheese,  or  milk.^  Even  as  regards  carbo- 
hydrate it  would  require  about  i  pound  3  ounces  of  rice  to  furnish 
the  daily  need  of  an  active  man.  This  would  entail  the  consumption 
of  about  5  pounds  of  cooked  rice  daily." 

Millet  and  Buckwheat. 

These  cereals*  are  not  used  as  human  food  in  this  country, 
although  they  are  by  no  means  of  low  nutritive  value,  but  stand 
midway  in  that  respect  between  wheat  on  the  one  hand  and  rice 
on  the  other.  Millet  is  freely  consumed  in  Africa,  being  the 
staple  diet  of  the  negroes  of  the  Upper  Nile,  and  in  some  Southern 
European  countries,  while  in  China  it  is  used  to  make  bread.  The 
dhoora  (sorgho-grass),  or  Indian  millet,  is  of  very  similar  composition. 
The  following  is  an  analysis  of  it  given  by  Professor  Church : 

Water     ..         ..         ..  ..  ..  12  2  per  cent. 

Protein ..  ..       82       ,, 

Fat  ..         ..         ..  ..  ..       4*2       ,, 

Carbohydrates..  ..  ..  ..  70*6       „ 

Cellulose  ..  ..  ..  ..       3-1        „ 

Mineral  matter  ..  ..  ..       1*7       ,, 

*  See  Kumagawa,  Virchow's  Arckiv,  1889,  cxvi.  370. 

'  It  is  interesting  to  note  that  in  countries  in  which  rice  is  largely  used  as  a 
daily  food  this  is  actually  done,  as  in  the  Italian  Risotto,  the  Turkish  Pilaff,  and 
the  Spanish  '  Polio  con  Riz. ' 

^  It  is  worth  observing,  too,  that  in  Eastern  countries  in  which  rice  takes  the 
place  of  bread  it  is  eaten  in  a  much  drier,  and  therefore  more  concentrated,  form 
than  it  is  in  Europe,  and  with  the  addition  of  various  sauces  and  condiments  to 
give  it  flavour  and  promote  its  digestion. 

*  Buckwheat  is  not  strictly  a  cereal,  but  belongs  to  the  Polygunaceae.  It  is 
considered  here  for  convenience. 


230  FOOD  AND  DIETETICS 

Buckwheat  is  about  equal  in  nutritive  value  to  millet,  but  contains 
much  more  cellulose  (lo  per  cent.).  It  is  usually  eaten  in  the  form 
of  a  porridge.  In  this  country  it  is  hardly  ever  used  as  human 
food,  but  it  is  freely  consumed  in  Brittany  and  Holland,  and  in  some 
parts  of  the  United  States. 

The  published  analyses  of  buckwheat  are  somewhat  discordant. 
Church  1  gives  the  following  as  the  composition  of  the  grain  when 
deprived  of  its  husk : 

Water        ..         ••         .,         ..         ..  13-4  per  cent. 

Protein 15-2 

Starch        ..         ..         ..         ..         ..  636 

Fat 34 

Cellulose    ..         ..         ..         ..         ..       21 

Mineral  matter     ..  ..  ..  ..       2 '3 

Another  analysis'^  of  buckwheat-flour  was  as  follows: 

Water        ..         .,         ,.         ..         ..  i4'2  percent. 

Protein       ..         ..         ..         ..         ..  92       ,, 

Carbohydrates      ..  ..  ..  ..  73'3       ,• 

Fat 1-8       „ 

Cellulose    ..         ..         ..         ..         ..  o"8       „ 

Mineral  matter     ..         ..         ..         ..       i'2      ., 


1  '  Food  ':  London,  1898  (Chapman  and  Hall),  p.  93. 

*  Leyden's  '  Handbuch  der  Ernahrungs  Tberapie,'  2nd  edition,  1903,  i.  99. 


[231  ] 


CHAPTER  XIII 

THE  PULSES— ROOTS  AND  TUBERS 

The  Pulses. 

In  this  group  are  included  peas,  beans,  and  lentils,  and  their  allies. 
The  edible  parts  of  these  resemble  the  grain  of  cereals  in  that  they 
are  to  be  regarded  as  storehouses  of  nourishment  for  the  young 
plant.  The  chief  chemical  characteristic  of  the  group  is  the  riclmess 
of  its  members  in  nitrogen,  in  virtue  of  which  fact  they  have  been 
described  as  '  the  poor  man's  beef.'  All  but  from  3  to  5  per  cent,  of 
the  total  nitrogen,  moreover,  is  in  the  form  of  protein  (Church). 
Why  the  young  pulse  should  require  so  much  more  nitrogen  than 
the  young  cereal,  it  would  be  difficult  to  say,  but  perhaps  it  is  on 
account  of  its  greater  rapidity  of  growth.  It  may  be  remembered 
that  there  is  a  special  provision  for  the  adequate  supply  of  nitrogen 
to  plants  of  this  group  in  the  form  of  little  nodules  on  their  roots, 
which  nodules  consist  of  masses  of  bacteria,  possessed  of  the 
remarkable  power  of  fixing  the  free  nitrogen  of  the  atmosphere  and 
passing  it  on  for  the  use  of  the  plant. 

The  chief  protein  found  in  the  pulses  is  called  legumin,^  also 
spoken  of  sometimes  as  vegetable  casein,  owing  to  its  close 
resemblance  to  the  principal  protein  of  milk.  So  much  is  this  the 
case,  that  a  kind  of  cheese  may  actually  be  prepared  from  beans. 
Legumin  is  able  to  unite  with  salts  of  lime,  and  the  resulting  com- 
pound is  not  soluble  in  water.  It  is  for  this  reason  that  peas  and 
other  pulses  do  not  readily  soften  if  the  water  in  which  they  are 
soaked  contains  much  lime,  i.e.,  is  hard.  The  addition  of  a  little 
bicarbonate  of  soda  to  the  water  throws  down  the  lime.  Hence 
the  importance  of  adding  soda  to  hard  water  in  which  pulses  are  to 
be  soaked.2  Magnesia,  which  resembles  lime  in  so  many  other 
respects,  has  no  effect  upon  legumin.' 

The  proteins  of  some  of  the  pulses  seem  to  be  especially  rich  in 

sulphur,  and  this,  by  giving  rise  to  sulphuretted  hydrogen  gas,  helps 

to  explain  their  tendency  to  produce  flatulence.     Beans  are  richer  in 

1  A.  nucleo-albumin  {Maly's  Jakres-Bericht  Thier-Chemie,  1897,  xxvii.  21). 
'  Richter  has  shown  {Archiv  /.  Hygiene,  1903,  xlvi.  264)  that  peas  are  not  so  well 
digested  and  absorbed  when  boiled  in  hard  water  as  they  are  when  cooked  in  soft. 
»  See  Striimpell,  Deut.  Archiv/.  Klin.  Med.,  1876,  xvii.  108. 


339  FOOD  AND  DIETETICS 

sulphur  than  peas,  while  lentils  contain  least  of  all.  The  ash  of  the 
pulses  is  poorer  in  phosphorus  than  that  of  the  cereals,  but  richer  in 
potash  and  lime.  The  pulses,  indeed,  contain  more  of  the  latter 
ingredient  than  any  other  form  of  vegetable  food. 

The  pulses  are  well  supplied  with  carbohydrates,  but  are  poor  in 
fat.  For  this  reason  they  go  well  with  fatty  foods  {e.g.,  bacon  and 
beans,  pork  and  pease  pudding),  and  are  improved  by  being  served 
with  sauces  containing  butter,  or  cooked  with  oil.  They  also  contain 
a  bitter  principle  which  renders  then  unpalatable  to  many  persons. 
It  should  be  added  that  they  contain  considerable  quantities  of 
purin -bodies,  in  consequence  of  which  the  excretion  of  uric  acid  is 
greater  after  their  use.  For  this  reason  they  are  sometimes  forbidden 
to  the  gouty.  Dried  peas  and  beans  require  prolonged  soaking  in 
order  to  soften  their  skins.  Even  haricots,  in  which  the  skin  is  com- 
paratively thin,  require  about  eight  hours  to  soften.  The  water  in 
which  they  are  soaked  should  be  soft  or  boiled.  The  reason  for  this 
was  given  above.  The  soaking  is  inevitably  accompanied  by  some 
loss  of  protein  and  mineral  matter,  and  also  of  carbohydrates ;  but 
it  has  the  advantage  of  removing  most  of  the  bitter  principle  in  the 
seeds.  The  amount  of  water  taken  up  is  very  great.  The  propor- 
tion of  water  in  dried  haricot  beans,  for  example,  rises  as  the  result 
of  soaking  and  boiling  from  14  per  cent,  up  to  73  per  cent.,  and  in 
the  case  of  peas  the  increase  is  from  9*7  up  to  86-9  per  cent.^  This 
increase  in  water  means,  of  course,  a  corresponding  increase  in  the 
weight  and  bulk  of  the  food,  and  must  always  be  taken  into  account 
when  comparing  the  relative  nutritive  values  of  the  pulses  and  meat. 

The  pulses  are  not  readily  digested  by  the  stomach.  As  Galen 
said :  '  They  are  harder  to  digest  than  other  foods  and  give  bad 
dreams.'  This  is  no  doubt  partly  owing  to  their  bulkiness  when 
cooked.  Thus,  5^  ounces  (150  grammes)  of  lentils  in  the  form  of 
a  mash,  or  about  a  soup-plateful,  remained  in  the  stomach  for  four 
hours,  and  200  grammes  of  peas  in  a  similar  form  for  four  hours  and 
a  quarter.  An  equal  weight  of  French  beans  (haricots  verts)  remained 
rather  longer  even  than  that. 

If  properly  prepared,  the  pulses  are  ahsorbed  in  the  intestine  very 
thoroughly.  Thus  the  protein  of  pea  or  lentil  flour  is  all  taken  up 
except  about  8  or  9  per  cent.^  when  200  grammes  (7  ounces)  are 
given  daily.  Even  when  the  amount  given  was  as  much  as  600 
grammes  (21J  ounces)  the  loss  was  only  as  follows  :^ 

^  Analyses  by  Katherine  J.  Williams, /owm.  of  Chem.  Soc,  1892,  IxL  226. 

*  Strumpell,  Deut.  Archiv  f.  Klin.  Med.,  1876,  xvii.  108. 

•  Rubner,  Ztit.  f.  Biolog.,  1880,  xvi.  119. 


THE  PULSES  %ii 

Dry  substance 9*1  per  cent. 

Protein      .,  ..         ..  ..         ..     17-5         „ 

Carbohydrate  ..         ..  ..  ..       36        „ 

Mineral  matter  ..  ..  ..  ..32-5         „ 

This  shows  that  the  protein  of  the  pulses,  if  given  in  a  state  of 
fine  division,  is  capable  of  very  good  absorption — almost  as  good, 
indeed,  as  that  of  gluten  when  given  in  the  form  of  macaroni,  in 
which  the  loss  is  11*2  per  cent.,  and  considerably  better  than  gluten 
when  taken  in  the  form  of  white  bread  (loss  about  20  per  cent.). 
On  the  other  hand,  the  loss  is  very  much  greater  if  the  food  is  not 
given  in  a  state  of  fine  division.  It  was  found,  for  example,  that  if  the 
lentils  were  simply  boiled  soft  and  taken  along  with  broth,  the  loss  of 
protein  rose  to  40  per  cent.^  It  will  be  noted  that  there  was  a  small 
loss  of  carbohydrate  even  on  pea  flour.  The  amount  of  it,  however, 
is  less  than  in  the  case  of  potatoes  or  carrots,  but  in  white  bread,  it 
will  be  remembered,  there  is  no  loss  of  carbohydrate  at  all. 

Some  extensive  investigations  on  the  absorption  of  different  forms 
of  legumes  have  been  made  in  recent  years  in  America.^  They 
showed  an  average  absorption  of  80  per  cent,  of  the  protein  and 
97  per  cent,  of  the  carbohydrates.  These  results  are  very  favourable 
when  it  is  remembered  that  the  legumes  constituted  the  major  part  of 
the  diet  in  the  subjects  studied. 

The  nutritive  value  of  the  pulses  is  undoubtedly  high.  Especially 
is  this  the  case  if  they  be  regarded  as  sources  of  protein.  It  would 
require  about  600  grammes  {i\  pounds)  of  pea  flour  to  supply  the 
amount  of  protein  required  daily  by  an  active  man.  Suppose  this 
were  to  be  given  in  the  form  of  pea  soup.  A  good  thick  soup  would 
contain  25  grammes — a  heaped  tablespoonful — in  each  plate.  The 
protein  value  of  this  would  be  equal  to  an  ounce  of  meat.  Twenty- 
four  platefuls  of  such  a  soup,  then,  would  require  to  be  taken  in  the 
day.  By  making  the  soup  with  milk  instead  of  water — an  excellent 
plan — the  amount  of  protein  in  it  would  be  trebled,  and  eight 
platefuls  would  suffice. 

The  600  grammes  of  pea  flour  would  hardly,  however,  contain  as 
much  carbohydrate  as  is  required,  and  would  be  very  deficient  in 
fat.  These  deficiencies  would  require  to  be  made  good  by  the 
addition  of  some  other  articles  to  the  diet,  or  by  increasing  the 
amount  of  pea  flour  consumed.  As  a  matter  of  fact,  it  has  been 
found  that  when  the  quantity  of  peas  eaten  amounts  to  960  grammes 
(34J  ounces)  in  the  twenty-four  hours,  all  the  demands  of  nutrition  are 

^  Strumpell,  Deut.  Archiv  f.  Klin.  Med.,  1876,  xvii.  108. 

'  Studies  on  the  Digestibility  and  Nutritive  Value  of  Legumes  (United  States 
Department  of  Agriculture,  Office  of  Experiment  Stations,  Bulletin  187,  1907). 


«34 


FOOD  AND  DIETETICS 


satisfied  ;^  but  it  is  very  doubtful  whether  anyone  could  go  on  con- 
suming this  quantity  for  any  length  of  time.  It  comes  then  to  this, 
that,  while  the  pulses  are  most  valuable  sources  of  protein,  they  are 
not  adapted  to  be  the  exclusive  diet  of  health.  As  a  cheap  and 
efficient  method  of  supplementing  the  deficiency  of  nitrogen  in  a 
purely  vegetable  diet,  however,  their  use  is  strongly  to  be  recom- 
mended, and  it  is  a  pity  that  they  are  not  more  largely  taken  advan- 
tage of  by  those  to  whom  economy  is  of  importance,  for  unquestionably 
the  pulses  are  amongst  the  cheapest  of  foods,  and  a  given  sum  will 
yield  more  protein,  if  invested  in  them,  than  in  any  other  way  (see 
Plate  III.).  It  remains  to  add  a  few  words  about  the  individual 
members  of  the  pulse  group.  Their  chemical  composition  is  shown 
in  the  following  tables : 

COMPOSITION  OF  PULSES.     (The  Means  0/ Many  Analyses.) 


Water. 

Protein. 

Carbo- 
hydrates. 

Fat. 

Cellu. 
lose. 

Mineral 
Matter. 

Green  peas 
Dried 

78-1 
130 

40 
21 'O 

160 

5.V4 

05 

I -8 

05 

60 

0-9 

2-6 

Prepared  pea  flour 

IO-2I 

27-98 

5^93 

1-97 

0  42 

249 

Lentils    . . 
Horse  beans  (dry) 
Broad  or  Windsor  beans 

117 
13  I 

23   2 

53-4 
509 

20 

1  7 

20 

55 

27 

33 

(dry)    

French  beans  (haricots 

8-4 

26  4 

586 

20 

10 

36 

verts)  . . 
Haricots    (haricots 

895 

13 

73 

04 

06 

07 

blancs) 

II  7 

23  0 

558 

23 

40 

32 

Scarlet  runners  (stewed) 
Soy  beans 
, ,    bean  flour  . . 
Peanuts 

Butter    beans    (ground 
unpeeled) 

9112 

II  0 

93 

83 

1-7 
329 
395 
24  0 

206 

37 
287 
28  2 
17  0 

626 

03 
181 
137 
443 

2-0 

29 

44 
40 

45 

03 

49 
5  3 
19 

43 

The  following  represents  some  recent  analyses  of  dried  pulses  by 
Balland.2 


Beans 
(Haricots). 

Lentils. 

Peas. 

Mini- 

Maxi- 

Mini- 

Maxi- 

Mini- 

Maxi- 

mum. 

mum. 

mum. 

mum. 

mum. 

mum. 

Water 

1000 

20  40 

1 1 70 

1350 

io-6o 

1420 

Protein 

13  81 

2516 

2032 

2424 

1888 

2348 

Fat 

098 

246 

058 

I  45 

122 

I  40 

Starch  and  sugar  . . 

5291 

6098 

5607 

6245 

5621 

61IO 

Cellulose     . . 

246 

462 

296 

3-56 

2  90 

552 

Ash 

238 

4-20 

1-99 

2-66 

226 

350 

>  Rabner,  {oe.  eit. 


•  Compt.  Rend.,  1897,  cxxv.  119. 


COMPOSITION  OF  THE  PULSES  235 

The  garden  pea  {Pisum  sativum)  is  eaten  either  fresh  (green  peas) 
or  dried.  Green  peas  cooked  in  the  usual  way  contain  from  12  to 
16  per  cent,  of  carbohydrate,  of  which  a  considerable  proportion  is 
sugar.  Of  beans  there  are  several  edible  varieties.  The  French  or 
kidney  bean  (Phaseolus  vulgaris)  is  eaten  either  in  the  young  state 
along  with  the  pod  (haricots  verts),  or  the  seeds  are  consumed  alone 
either  fresh  or  after  drying  (haricots  blancs).  The  amount  of 
cellulose  in  the  pod  causes  it  to  be  digested  and  absorbed  with 
difficulty,  and  on  that  account  it  is  a  wasteful  form  of  food.  Allied 
to  the  French  bean  is  the  scarlet  runner  (Phascoliis  multiflorns),  which 
when  stewed  constitutes  '  Turkish  beans.'  The  broad  or  Windsor 
bean  {Faba  vulgaris)  is  eaten  either  in  the  fresh  or  dry  state.  A 
coarser  variety  of  the  same  plant  is  the  horse  or  field  bean.  It  is 
not  usually  consumed  as  human  food. 

Beans  are  on  the  whole  richer  in  protein  than  peas,  but  contain 
also  more  sulphur,  and  are  more  apt  to  cause  flatulence. 

The  Lentil  {Lens  esculenta)  is  even  richer  in  protein  than  either 
the  pea  or  the  bean,  and,  as  a  rule,  the  smaller  varieties  of  it  are 
richer  in  that  constituent  than  the  larger.  Egyptian  lentils  are 
amongst  the  best.  Lentils  contain  little  sulphur,  and  are  more 
digestible  and  less  apt  to  cause  flatulence  than  either  peas  or  beans. 
The  ash  of  the  Egyptian  lentil  is  particularly  rich  in  iron. 

The  patent  preparation  known  as  Revalenta  Arabica  consists 
mainly  of  lentil  flour.  The  following  is  the  result  of  an  analysis 
which  I  recently  made  of  it. 


Moisture  ..         ..       g-i  per  cent. 
Protein     ..         ,.     22  o        ,, 
Fat  ..         ..       1-5 


Carbohydrates       ..     65*2  per  cent. 
Mineral  matter       ,.       2-2 


It  is  really  poorer  in  nitrogen  than  pure  lentil  flour.  The  latter 
costs  2|d.  per  pound ;  Revalenta,  3s.  6d.  It  certainly  in  no  way 
merits  the  very  high  claims  sometimes  advanced  for  it.  A  soup- 
plateful  of  Revalenta  made  from  three  moderately- heaped  table- 
spoonfuls  (60  grammes)  yields  thirty-six  Calories  less  than  a  similar 
quantity  of  good  porridge,  but  is  slightly  richer  in  /protein  and 
mineral  matter.  In  other  words,  it  is  rather  more  valuable  as  a 
tissue-builder  than  porridge,  but  is  not  so  good  as  a  source  of  heat 
or  energy.  It  must  be  remembered,  too,  that  it  is  considerably 
more  expensive. 

The  Soy  Bean  [Glycine  hispida)  is  the  richest  of  all  the  pulses  in 
protein,  and  has  also  a  large  amount  of  fat,  but  very  little  starch. 
For  this  reason  it  is  of  use  as  a  bread  substitute  in  diabetes,  a  flour 


236  FOOD  AND  DIETETICS 

being  prepared  from  it  and  made  into  loaves  or  biscuits.  In  China 
and  Japan  it  is  extensively  eaten  in  the  form  of  soy  cheese,  and  as 
various  sauces  and  pastes,  all  of  which  are  rich  in  protein  and  so  are 
fitted  to  supplement  the  deficiencies  of  rice.  It  is  also  grown  in 
Southern  Europe.  A  very  interesting  *  synthetic  '  milk  has  lately 
been  prepared  from  the  soy  bean,  which  has  a  close  resemblance  in 
physical  and  chemical  properties  to  cow's  milk,  and  will  probably 
be  able  to  replace  the  latter  to  a  large  extent  for  many  purposes. 

The  Peanut  (Arachis  hypogaa),  although  botanically  one  of  the 
pulses,  really  resembles  more  closely  the  true  nuts.  Like  these,  it  is 
rich  in  proteins  and  fat,  and  may  be  used  as  a  diabetic  food.  It 
enters  into  the  composition  of  the  patent  food  known  as  *  Nutrose,* 
and  after  expression  of  the  oil  it  forms  cakes  for  cattle. 

Eoots  and  Tubers. 

We  have  already  seen  that  the  chief  bulk  of  the  grain  of  cereals  Is 
to  be  regarded  as  a  storehouse  of  nutriment  for  the  use  of  the  young 
plant.  The  roots  and  tubers,  the  consideration  of  which  will  occupy 
our  attention  in  this  section,  may  be  regarded  in  like  manner  as 
reserves  of  nourishment  for  the  use  of  the  adult  plant  itself.  During 
the  prosperous  days  of  spring  and  early  summer  the  plant  lays  by 
of  its  superfluity  against  the  certain  adversity  of  autumn.  The 
reserve  nutriment  so  laid  up  is  almost  entirely  in  the  form  of  carbo- 
hydrates— chiefly  starch.  Protein  and  fat  are  scarcely  represented 
at  all.  Hence  it  is  obvious  that  in  using  the  roots  and  tubers  as 
foods  we  are  tapping  a  supply  of  only  one  of  our  nutritive  elements, 
and  that  fact  must  never  be  lost  sight  of  in  estimating  the  value  of 
this  class  of  vegetable  foods. 

It  remains  to  be  added  that,  of  the  small  proportion  of  nitrogenous 
matter  which  these  foods  contain,  only  part,  and  thai  not  infre- 
quently a  very  small  part,  is  present  in  the  form  of  protein.  On 
the  other  hand,  they  are  by  no  means  destitute  of  mineral  ingredi- 
ents, mainly  salts  of  potash,  and  the  presence  of  these  confers 
upon  the  roots  and  tubers  a  greater  value  as  articles  of  diet  than 
they  would  otherwise  be  entitled  to  possess. 

As  far  back  as  the  year  1781,  Letheby  tells  us,  Sir  Gilbert  Blane, 
in  his  work  on  '  Diseases  of  the  Fleet,'  alluded  to  the  beneficial 
action  of  the  potato  in  scurvy ;  and  the  late  Dr.  Baly  remarked,  in 
his  inquiries  into  the  diseases  of  prisoners,  that  wherever  potatoes 
were  used  scurvy  was  unknown. 

Another  general  consideration  which  must  be  borne  in  mind  is 
that  the  mere  cooking  of  these  foods  robs  them  of  a  very  large 


ROOTS  AND  TUBERS 


237 


proportion  of  their  mineral  ingredients  and  of  some  of  the  nitro- 
genous matter  in  which  they  are  already  so  deficient.  For  this 
reason  the  water  in  which  they  are  cooked  should  also  be  utilized  as 
far  as  possible,  or,  which  is  preferable,  they  should  be  cooked  by 
means  of  steam. 

AVERAGE   COMPOSITION    OF    EDIBLE   PORTION   OF  ROOTS   AND 

TUBERS. 


Water. 

Protein. 

Carbo- 
hydrate. 

Fat. 

Fibre. 

Ash. 

Extrac- 
tives. 

Potatoes           . . 

78-3 

2-2 

18 -o 

o-i 

0-4 

I'O 

I  4 

Carrots            . .         . . 

857 

05 

(Albu- 
minoid 
NX625) 

ID- 1 

03 

I'5 

09 

10 

,.       (cooked)         .. 

93  4 

053 

339 

017 

1-8 

0  14 

Turnips           . .         , . 

903 

09 

50 

015 

1-8 

0-8 

I-I 

(cooked) 

9725 

0  32 

065 

006 

1-2 

0  32 

Radishes 

908 

14 

46 

01 



07 

Beetroots 

839 

05 

no 
(10  per 
cent  of 
sugar) 

01 

30 

09 

z-o 

„        (cooked)      . . 

94-8 

044 

283 

0  06 

13 

03 

Parsnips 

801 

1-4 

14  I 

10 

21 

13 

(cooked)     .. 

9728 

022 

I  46 

0  29 

072 

012 

Artichokes 

79-8 

23 

145 

03 

20 

10 

(cooked)  .. 

91  6 

1-8 

46 

008 

09 

0  61 

Onions . . 

891 

1-6 

6-3 

03 

20 

06 

Sweet  potatoes 

729 

1-6 

225 

05 

1-8 

07 

Yams 

796   , 

22 

153 

05 

09 

15 

As  regards  the  digestibility  of  these  foods  as  a  class,  it  may  be 
said  that  it  depends  largely  on  the  amount  of  cellulose  which  each 
happens  to  contain,  but  it  is  true  of  all  of  them  that  they  are  only 
indifferently  absorbed,  and  are  prone,  by  reason  of  their  bulk,  to 
derange  the  stomach  and  bowels  if  eaten  in  large  quantity. 

We  may  now  pass  to  a  detailed  examination  of  the  chief  members 
of  the  group,  beginning  with  the  potato. 

Potatoes. 

The  potato  was  introduced  into  this  country  more  than  300  years 
ago,i  and  since  that  time  it  has  steadily  increased  in  popular  favour, 
until  it  may  now  be  regarded  as  one  of  the  most  important  staple 
articles  of  diet. 


^  A  full  account  of  the  history  of  the  discovery  of  the  potato  will  be  found  in 
Weyl's  'Handbuch  der  Hygiene,'  iii.  257. 


238 


FOOD  AND  DIETETICS 


If  one  cuts  a  raw  potato  across  with  a  sharp  knife  and  looks  at 
the   cut    surface,   three    distinct    layers   can    easily    be   made   out 

(Fig.  1 8).  These  are  (i)  the 
thin  outer  skin.  (2)  A  broader 
layer  inside  the  skin  called  the 
*  fibro-vascular  layer.'  It  con- 
tains a  small  amount  of  pigment, 
and  turns  green  when  exposed 
to  the  light,  giving  the  potato  an 
unpleasant  taste.  (3)  The  flesh  of 
the  potato,  which  makes  up  the 
rest  of  its  bulk.  On  more  care- 
ful inspection  this  is  seen  to  be 
divided  into  a  central  core  and 
an  outer  zone  which  surrounds  it. 
These  different  layers  form 
the  following  proportions  of  the 
whole  potato : 


Fig.  18. — Cross  Section  or  a  Potato. 

a,  Skin  ;  b,  Fibro-vascular  laver  ;  c.  Outer 

zone  of  flesh  ;  d,  Central  core. 


1.  Outer  rind 

2.  Fibro-vascular 

layer 

3.  Flesh  . . 


=  2\  per  cent. 

=  ^    .. 


The  importance  of  recognising  them  is  due  to  the  fact  that  they 
differ  considerably  in  chemical  composition,  as  is  shown  in  the 
following  table  •} 


NiTROGKN. 

As 

Protein. 

rotal. 

Fat. 

025 

0  43 

0-8 

024 

0-36 

01 

018 

032 

O'l 

0  19 

0  32 

01 

Carbo- 
hydrate. 
14  6 

Mineral 

Matter. 

1-8 

13-3 
16  0 

II 

08 

157 

09 

COMPOSITION  OF  A  POTATO. 


Water. 
Outer  rind     . .  . .     8o-i 

Fibro-vascular  layer      83  2 

Flesh Six 

Whole  potato  ..     813 

The  fibro-vascuL.r  layer  is  seen  to  be  considerably  richer  in 
mineral  matter  and  protein  than  the  flesh,  and  in  peeling  it  off  with 
the  rind  we  lose  these  valuable  ingredients. 

If  the  flesh  of  the  potato  is  squeezed  it  can  be  separated  into  a 
solid  part  and  a  juice.  The  former  consists  mainly  of  starch  ;  it  has 
only  15  per  cent,  of  the  nitrogenous  matter.     The  juice  consists  of 


1  See  Bull.  43,  United  States  Department  of  Agriculture,  Office  of  Experiment 
Stations,  Washington,  1897. 


THE  COOKING  OF  POTATOES  «39 

water  holding  in  solution  nitrogenous  matter  and  salts.  It  contains 
fully  85  per  cent,  of  the  total  amount  of  nitrogenous  matter  con- 
tained in  the  potato. 

It  must  be  clearly  realized  that  by  no  means  all  of  this  nitro- 
genous matter  is  present  in  the  form  of  protein.  Of  the  total 
amount  of  nitrogen  in  a  potato,  only  49  per  cent,  is  contained  in 
proteins,  the  remainder  being  in  the  form  of  ammonia  compounds 
(amides,  e.g.,  asparagin)  and  salts.  The  failure  to  recognise  this 
fact  has  led  people  to  assume  that  the  whole  of  the  nitrogen  of  the 
potato  represents  protein,  and  so  greatly  to  overrate  the  value  of 
potatoes  as  tissue-building  food. 

The  richer  the  potato  is  in  protein — in  other  words,  the  juicier  it  is 
— the  more  *  waxy '  is  it  when  cooked,  for  the  coagulated  protein  holds 
together.  For  this  reason  young  potatoes,  which  contain  more  juice 
than  those  which  are  older  and  more  starchy,  have  a  more  sohd  and 
waxy  consistence  when  cooked  than  the  latter. 

The  richness  of  the  potato  In  starch  is  its  most  striking  chemical 
characteristic,  and  causes  it  to  be  one  of  the  chief  commercial 
sources  of  that  substance.  Dextrin  and  '  British  arrowroot '  and 
many  other  things  are  prepared  from  it.  The  starch  grain  of  the 
potato  is  of  specially  large  size,  and  seems  to  be  more  easily  attacked 
by  ferments  than  most  forms  of  starch,  probably  because  it  does  not 
contain  much  '  starch  cellulose.*  Owing  to  their  readiness  to  undergo 
fermentation  potatoes  should  be  avoided  in  some  diseased  conditions, 
such  as  dilatation  of  the  stomach. 

The  most  important  mineral  ingredients  of  potatoes  are  salts  of 
potash,  and  potatoes  are  one  of  the  chief  sources  from  which  we 
obtain  our  supply  of  these  salts.  Part  of  the  potash  is  united  with 
citric  acid.  Potatoes,  like  all  tubers,  may  have  their  composition, 
and  consequently  their  nutritive  value,  profoundly  modified  by 
the  mode  in  which  they  are  cooked.  The  chief  danger  is  that 
their  nitrogenous  constituents  and  mineral  salts  may  be  dissolved 
out.  The  amount  of  starch  and  water  which  they  contain  is 
scarcely  ever  affected.^  These  facts  are  brought  out  in  the  following 
analyses  -.^ 

1  See  analyses  of  cooked  potatoes  by  Katherine  Williams, /owrw.  of  Chtm.  Soc, 
1892,  Ixi.  226. 

■•^  United  States  Department  of  Agriculture,  Office  ot  Experiment  Statioiu^ 
Bull.  43,  p.  30. 


240 


FOOD  AND  DIETETICS 


THE  LOSS  OF  MATERIAL  DURING  THE  PROCESS 

POTATOES. 

OF  COOKING 

Dry 

Matter. 

NiTROGKN. 

Carbo- 
hydrates. 

Protein. 

Non- 
Protein. 

Total. 

Ash. 

Skins  removed  be/ore 
Boiling. 

Water  cold  at  beginning 
of  test 

Water  hot  at  beginning 
of  test  

Per  cent. 
37 

40 

Per  cent. 
43 

33 

Per  cent. 
12  9 

179 

Per  cent. 
8-3 

100 

Per  cent. 
25 

28 

Per  cent 
170 

17-4 

Average  .. 

39 

3-8 

154 

92 

27 

17-2 

Boiled  tvith  Skins  on. 

Water  cold  at  beginning 
of  test  

Water  hot  at  beginning 
of  test 

03 
03 

06 
04 

06 

17 

06 
10 

02 

01 

19 
12 

Average  .. 

03 

05 

II 

08           0-2      1       1-6 

The  kind  of  water  in 
which  they  are  soaked 
does  not  make  any  differ- 
ence. It  has  been  calcu- 
lated that  if  a  bushel  of 
potatoes  were  peeled  and 
soaked  before  being  boiled 
the  loss  of  nutrients  would 
be  nearly  equivalent  to 
the  amount  contained  in 
I  pound  of  beefsteak.  It 
follows  from  this  that 
potatoes  should  either  be 
steamed  or  cooked  in  their 
'jackets.' 

The  accompanying  dia- 
gram shows  the  per- 
centage composition  of  a 
potato,  and  the  loss  of 
nutrients  which  it  sustains  Fig 
when  cooked  by  the  usual 
method. 


19.  —  Percentage  Composition  of  a 
Potato  and  loss  of  each  Constitdknt  on 
Boiling. 


THE  COOKING  OF  POTATOES 


«4i 


The  composition  of  raw  and  cooked  potatoes  from  the  average  of 
many  American  analyses  is  as  follows  :^ 


Refuse. 

Water. 

Pro- 
tein. 

Fat. 

Carbohydrates. 

Ash. 

Kind  of  Food. 

Sugar, 

Starch, 

etc. 

Crude 
Fibre. 

Fuel  Value 
per  Pound. 

Per 

Per 

Per 

Per 

Per 

Per 

Per 

Calories. 

cent. 

cent. 

cent. 

cent. 

cent. 

cent. 

cent. 

Potato,  as  purchased   . . 

20 -o 

626 

1-8 

01 

138 

09 

0-8 

310 

Potato,  edible  portion  . . 



78-3 

22 

o-i 

i8-o 

04 

10 

375 

Potato,  boiled    . . 



75 '5 

25 

0"I 

20 '3 

06 

i-o 

440 

Potato,     mashed     and 

seasoned 



75 '1 

2-6 

30 

17-8 

15 

505 

Potatoes    fried   in    fat. 

1 

'  Potato  chips  ' 



2'2 

6-8 

398 

-      467 

45 

2,675 

Potato,  evaporated 



71 

8-5 

0-4 

809 

31 

1,680 

White  bread      . . 



35'3 

92 

13 

526       0-5 

i-i 

1. 215 

The  digestibility  of  potatoes  in  the  mouth  and  stomach  depends 
largely  on  the  form  in  which  they  are  eaten.  They  are  less  digestible 
when  eaten  as  lumps  than  in  a  puree  ;  and  *  mealy  '  potatoes  are 
more  digestible  than  '  waxy.' 

Two  medium-sized  potatoes  (weighing  together  5J  ounces)  when 
boiled  and  eaten  in  the  usual  way  remain  for  about  two  to  two  and 
a  half  hours  in  the  stomach — that  is,  a  shorter  time  than  a  similar 
weight  of  bread. 

In  the  intestine  potatoes  are,  on  the  whole,  very  well  absorbed. 
This  is  owing  to  the  fact  that  they  contain  much  starch  and  little 
cellulose.  Even  when  the  quantity  consumed  daily  amounts  to 
3^  pounds,  92-|  per  cent,  of  the  starch  and  70  per  cent,  of  the  total 
nitrogen  enters  the  blood. 

Potatoes  are,  however,  by  no  means  suited  to  constitute  the  sole, 
or  even  the  staple,  diet  of  man.  They  are  much  too  bulky,  and 
contain  too  little  protein  in  proportion  to  their  starch.  Thus,  it 
would  require  about  22  pounds  of  potatoes  to  yield  even  118  grammes 
of  protein  daily,  while  this  quantity  would  contain  more  than  four 
times  as  much  carbohydrate  as  one  really  needs.  As  a  matter  of 
fact,  however,  Rubner  has  found  that  6^  pounds  of  potatoes  are 
enough  to  furnish  3,000  Calories  of  energy  and  to  prevent  any  loss 
of  bodily  protein.  This  is  probably  to  be  explained  by  the  relatively 
enormous  quantity  of  carbohydrates  {i.e.,  protein-sparers)  which 
such  a  diet  contains. 

An  experiment  mentioned  by  Pereira^  illustrates  this  fact  very 
well.     In  the  year  1840  some  experiments  with  a  potato  die*-  v/ere 

1  United  States  Department  of  Agriculture,  Farmers'  Bulletin  295,  1907. 
'  '  Food  and  Diet,'  p.  372. 

16 


242  FOOD  AND  DIETETICS 

made  in  a  prison  at  Glasgow.  Ten  of  the  prisoners,  consisting  of 
young  men  and  boys,  were  put  on  a  diet  of  6  pounds  of  potatoes 
daily.  At  the  end  of  the  experiment  (the  duration  of  which  is  not 
stated)  the  majority  of  the  subjects  had  gained  considerably  in 
weight,  and  all  expressed  themselves  as  quite  satisfied  with  the 
potatoes,  and  regretted  the  change  back  to  ordinary  fare.  It  must 
be  added,  however,  that  these  prisoners  were  only  engaged  in  light 
work,  and  the  state  of  their  nitrogen  balance  was  not  investigated. 

Even  granting  that  6  pounds  of  potatoes  per  day  is  sufficient  to 
supply  fully  all  the  needs  of  the  body,  it  must  be  evident  that  this 
quantity  is  still  unduly  bulky,  weighing  as  it  does  about  twice  as 
much  as  an  ordinary  mixed  diet.  The  result  of  its  continued  use 
would  be  an  undue  burdening  of  the  stomach  and  bowels,  cul- 
minating in  dilatation,  if  not  disease,  of  these  organs.  The  so-called 
'  potato  belly '  of  the  Irish  peasant  is  an  example  of  such  a  result. 

It  must  also  be  borne  in  mind,  in  estimating  the  nutritive  value  of 
potatoes,  that  much  of  their  nitrogen  is  in  the  form  of  substances 
which  do  not  belong  to  the  protein  group.  Of  these  substances 
asparagin^  is  one  of  the  chief.  It  contains  21-2  per  cent,  of  nitrogen. 
Now,  the  direct  nutritive  value  of  asparagin  is  nil,  but  there  is 
reason  to  believe  that  it  plays  a  useful  part  in  the  intestine  by 
limiting  putrefaction,  and  so  sparing  proteins  from  destruction.  It 
may  also  promote  the  absorption  of  proteins  and  carbohydrates  into 
the  blood.  In  the  case  of  herbivorous  animals  these  functions  may 
be  useful,  but  in  carnivora  and  mixed  feeders,  which  eat  plenty  of 
protein,  they  are  superfluous. ^ 

As  regards  economic  value,  potatoes  must  be  regarded  as  a  cheap, 
but  by  no  means  the  cheapest,  kind  of  food.  Thus,  when  potatoes 
are  selling  at  id.  and  bread  at  i^d  per  pound  the  former  are  two 
or  three  times  dearer  than  the  latter.'  From  the  point  of  view  of 
national  economy,  however,  potatoes  are  undoubtedly  a  cheap  food. 
Thus,  Boussingault  found  that  a  given  piece  of  land  produces : 


Wheat. 

Rye. 

Peas. 

Potatoes. 

Protein 

510 

440 

560 

950 

Starch 

..     1.590 

1,196 

780 

6,840 

Ash   .. 

90 

62 

60 

323 

Allied  to  the  potato,  though  not  now  eaten  in  this  country,  are  the 
sweet  potato  and  the  yam. 

^  Asparagin =amido-succinamic  acid. 

"^  See  Kellner,  Maly's  Jahres-Bericht  Tkier-Chemte,  1897,  xxvii.  721,  and  Gabriel, 
Zeit.  f,  Biolog.,  1892,  xxix.  115;  also  Konig,  '  Nahrungsmittel  Chemie,'  Bd.  i, 
p.  119.  and  F.  Voit,  "  Ergebnisse  der  Physiologic,'  I.,  Abth.  i,  1902. 

•  Smith,  '  Foods,'  p.  200. 


THE  TURNIP 


243 


The  Sweet  Potato  (batatas)  is  cultivated  in  hot  countries,  and  is 
largely  eaten  in  the  United  States.  It  used  to  be  eaten  in  England 
before  the  present  potato  was  introduced,  and  it  is  to  it  that  Shake- 
speare refers  when  he  makes  Falstaff  say,  *  Let  the  sky  rain  potatoes  !' 

The  Yam  is  the  tuber  of  a  tropical  climbing  plant  and  is  much 
larger  than  the  potato,  but  resembles  it  in  taste. 

The  composition  of  the  sweet  potato  and  yam  is  represented  in 
the  table  on  p.  237.  They  are  fully  equal  to  the  ordinary  potato  in 
nutritive  value. 


LOSS 


64^ 


26% 


Fig.  20. — Percentage  Composition  o»  a 
Turnip. 


Fig.  21. — Percentage  Com- 
position OF  A  Carrot,  and 
Loss  OF  EACH  Nutritive 
Constituent   by  Boiling. 


Thb  Turnip. 

The  chemical  composition  of  a  turnip  is  graphically  represented  in 
Fig.  20.  It  is  difficult  to  realize  that  an  apparently  solid  object  like 
a  turnip  really  contains  more  water  than  a  fluid  like  milk  ;  yet  such 
is  the  fact.  A  turnip  contains  almost  no  protein,  most  of  its  nitrogen 
being  in  a  non-protein  form.  Carbohydrates  are  more  abundantly 
represented  than  any  other  nutritive  ingredient,  but  even  they  only 
amount  to  5  per  cent.  Curiously  enough,  none  of  this  is  in  the  form 
of  starch,  that  substance  being  left  out  in  the  turnip's  composition. 


144  FOOD  AND  DIETETICS 

*  Pectose '  bodies  make  up  the  bulk  of  the  carbohydrate  present. 
The  nutritive  value  of  these  has  already  been  discussed  (p.  163) 
Seeing  that  starch  and  sugar  are  absent,  there  seems  to  be  no  reason 
why  turnips  should  be  forbidden  to  diabetics. 

A  consideration  of  the  above  facts  shows  that  the  turnip  can  never 
be  regarded  as  an  important  form  of  food,  a  conclusion  which  is 
accentuated  by  the  fact  that  the  white  turnip  eaten  at  the  table, 
though  finer  in  flavour,  is  of  even  less  nutritive  value  than  the 
coarser  '  swede.* 

Carrots  are  decidedly  more  nutritious  than  turnips,  mainly  owing 
to  their  richness  in  sugar,  of  which  they  contain  nearly  10  per  cent, 
either  as  cane  or  fruit  sugar.  The  amount  of  protein  which  they 
possess  is  a  negligible  quantity,  but  their  mineral  salts  are  of  some 
value.  The  composition  of  a  carrot,  and  the  loss  of  nutrients  which 
it  sustains  on  boiling,  are  represented  in  Fig.  21. 

It  has  been  found  ^  that  the  following  is  the  loss  of  nutrients  from 
the  intestine  on  a  diet  of  carrots  and  fat : 

Total  solids  lost  ..  ..  ..  =207  per  cent. 

,,      nitrogen  lost      ..  ..  ..  =390         „ 

„      carbohydrates  lost  ..  ..  =i8-2         „ 

„     mineral  constituents  ..  ..  =338         „ 

Carrots  cannot,  therefore,  be  regarded  as  at  all  a  digestible  form 
of  food.  Nor  are  they  easily  disposed  of  by  the  stomach,  for 
5J  ounces  remain  there  for  three  hours  and  twenty  minutes. 

Compared  with  the  turnip  and  carrot,  a  raw  Beetroot  is  a  com- 
paratively valuable  source  of  food.  Here,  again,  this  is  owing  to 
the  fact  that  it  contains  a  large  amount  of  cane-sugar.  The  ordinary 
garden  beet  contains  nearly  as  much  sugar  as  the  '  sugar  beet,'  and 
by  special  cultivation  the  latter  can  be  made  to  contain  15  per  cent. 
of  cane-sugar.  In  the  process  of  cooking,  however,  much  sugar  is 
lost,  so  that  ordinary  beetroot  as  it  comes  to  the  table  does  not 
contain  more  than  3  per  cent. 

Like  the  carrot  and  turnip,  the  beetroot  is  of  almost  no  value  as  a 
sotirce  of  protein.  It  contains  altogether  less  than  2  per  cent,  of 
nitrogenous  matter,  and  even  of  this  only  a  fraction  is  in  a  protein 
form.     The  exact  proportions  are : 

35  per  cent,  of  total  nitrogen    . .     =  protein. 
39  ,,  ,.  „  ..     =amides. 

36  ,,  ,,  ,,  ..     =  ammonia  salts  and  nitrates. 

The  beetroot  is  also  richer  in  cellulose  than  most  tubers.     The 
addition  of  vinegar  to  slices  of  beetroot  helps  to  soften  the  latter, 
^  Rubner,  Zeit.J.  B-^lcg.,  1879,  xv.  115. 


TAPIOCA,  SAGO  AND  ARROWROOT  245 

while  it  does  not  interfere  with  the  digestion  of  the  other  carbo- 
hydrates, seeing  that  these  are  already  in  the  form  of  sugar. 

Parsnips  belong  to  the  same  order  as  the  carrot.  In  the  raw 
state  they  are  fairly  rich  in  starch  and  sugar,  but  lose  much  of  the 
latter  in  the  process  of  cooking. 

Jerusalem  artichokes  resemble  turnips  in  containing  no  starch, 
but  are  fairly  rich  in  carbohydrates  belonging  to  the  gummy  series, 
which  make  them  very  mucilaginous  when  boiled.  They  also 
contain  a  little  sugar  and  about  2  per  cent,  of  the  peculiar  carbo- 
hydrate inulin,  the  nutritive  value  of  which  is  unknown.  It  is 
certainly  better  borne  by  diabetics  than  other  forms  of  carbohydrate, 
and  may  be  allowed  in  mild  cases  (Von  Noorden).  About  half  of  the 
nitrogen  artichokes  contain  is  in  a  non-protein  form. 

Onions  are  chiefly  valued  for  their  pungent  oil,  which  makes  them 
useful  flavouring  agents.  They  are  thus  to  be  regarded  as  condi- 
ments rather  than  foods.  The  large  Spanish  onion,  however,  is 
richer  in  nutrients,  and  may  rank  as  a  food.  Onions  are  valuable 
in  cases  of  constipation,  probably  owing  to  their  richness  in  cellulose. 

Tapioca,  Sago  and  Arrowroot. 

These  are  to  be  regarded  simply  as  special  forms  of  starch. 

Tapioca  is  derived  from  the  roots  of  South  American  cassava 
plants  belonging  to  the  Spurge  order  (Euphorbiaceae).  Curiously 
enough,  one  of  these  —  the  bitter  cassava  {Manihot  utilissima)  — 
contains,  mixed  up  with  the  starch,  a  milky  juice  in  which  is  present 
a  good  deal  of  that  dangerous  poison  prussic  acid.  In  preparing 
tapioca  the  juice  is  washed  away  from  the  grated  root  and  the 
starch  allowed  to  settle.  It  is  then  collected  and  dried  on  hot  metal 
plates.  The  process  of  drying  has  the  effect  of  rupturing  most  of 
the  starch  grains.  Tapioca  as  found  in  the  market  contains  about 
1 1^  per  cent,  of  water  and  87I  per  cent,  of  starch,  along  with  traces 
of  protein  and  mineral  matter,  and  has  a  fuel  value  of  1,650  Calories 
per  pound.  Pure  starch  contains  only  2  per  cent,  of  water,  and  a 
pound  of  it  furnishes  1,825  Calories,  so  that  weight  for  weight  pure 
starch  is  considerably  more  nourishing  than  tapioca. 

Tapioca  remains  a  considerable  time  in  the  stomach.  Forty 
grammes  of  it  in  the  form  of  a  thick  gruel  (about  a  soup-plateful)  had 
not  entirely  left  the  stomach  until  after  the  lapse  of  two  hours  and  forty, 
minutes  (Penzoldt).  Its  use  should,  therefore,  be  avoided  in  cases 
in  which  it  is  desirable  to  lighten  the  labours  of  the  stomach. 

Experiments  upon  the  absorption  of  tapioca  in  the  intestine  have 


246  FOOD  AND  DIETETICS 

not  been  performed,  but  consisting  as  it  does  of  starch  alone,  one 
would  expect  it  to  be  absorbed  very  completely. 

Sago  is  derived  from  the  pith  of  the  sago  palm.  The  trees  are 
felled,  split,  and  the  starch  washed  out.  It  is  then  dried,  and  con- 
verted into  pearl  sago  by  granulating.  One  tree  should  yield  about 
500  pounds  of  sago.  Commercial  sago  contains  867  per  cent,  of 
starch. 

Arrowroot  is  obtained  from  the  rhizome  of  a  West  Indian  plant 
{Maranta  anindinacea).  The  roots  are  mashed  up,  mixed  with  water, 
and  the  starch  allowed  to  settle.  When  dried,  it  constitutes  ordinary 
arrowroot.  The  superiority  of  Bermuda  arrowroot  to  the  other 
varieties  is  due  to  greater  care  in  manufacture.  The  starch,  having 
been  washed  away  from  the  mashed  roots  and  strained  through 
muslin,  is  allowed  to  settle,  and  is  subsequently  dried  in  flat  copper 
pans  covered  with  gauze.  When  dry,  it  is  packed  by  means  of 
German-silver  shovels  into  new  barrels  lined  with  paper  stuck  in 
with  arrowroot  paste.  All  these  precautions  are  necessary  to  prevent 
the  arrowroot  from  becoming  contaminated,  as  it  is  so  apt  to  be,  by 
foreign  flavours.  For  a  similar  reason  it  is  exported  on  deck  under 
covers,  lest  it  may  be  affected  by  effluvia  from  the  cargo  in  the 
hold. 

Arrowroot  contains  i6h  per  cent,  of  water,  and  82 J  per  cent,  of 
starch,  along  with  only  about  o'S  per  cent  of  protein  and  0*2  per 
cent,  of  mineral  matter. 

Tlie  composition  of  these  preparations  when  cooked  by  boiling 
and  ready  for  eating  is  as  follows  :^ 


Sago. 

Arrowroot. 

Water 

,     89  00  per  cent. 

93 '4 1  per  cent 

Protein 

.       1-38         .. 

030 

Fat 

0  '04         „ 

trace 

Starch 

•       937 

610        „ 

Cellulose 

0  01         ,, 

O'OI           ,, 

Mineral  matter 

o-o8        „ 

0'02            „ 

Tous  les  Mois  resembles  arrowroot  very  closely.  It  is  derived 
from  the  root  of  Canna  edtdis,  a  West  Indian  plant.  It  has  an 
extraordinarily  large  starch  grain — the  largest  known,  indeed  ;  but 
apparently  it  is  poor  in  starch  cellulose,  for  it  is  very  easily  digested, 
and  makes  excellent  blancmange. 

Salep  is  a  starchy  preparation  derived  from  the  roots  of  various 
species  of  orchis,  and  imported  into  England  from  Smyrna. 

The  digestibility  of  arrowroot  and  its  allies  in  the  stomach  is 
probably  much  the  same  as  in  the  case  of  tapioca,  and  their  absorp- 

^  Analyses  by  Katherine  J.  Williams  {lot.  cit.,  footnote,  p.  239). 


TAPIOCA,  SAGO  AND  ARROWROOT  247 

tion  in  the  intestine  is  exceedingly  complete.  This  gives  them  a 
special  value  in  the  treatment  of  diarrhoea. 

As  regards  the  nutritive  value  of  all  these  preparations,  it  must  be 
remembered  that  they  are  simply  agreeable  forms  of  starch;  in  other 
words,  they  consist  almost  entirely  of  carbohydrate,  and  should 
therefore  not  be  eaten  alone,  but  along  with  substances  rich  in 
protein  and  fat.  Eggs  and  milk  are  typical  examples  of  such 
substances,  and  accordingly  one  finds  that  people  have  made 
puddings  of  tapioca,  sago,  or  arrowroot  along  with  milk  and  eggs 
before  anything  was  known  of  the  chemical  constituents  of  the  diet. 
Tapioca  pudding  has  something  like  the  following  composition : 

Water        ..         ..         ..         ..         ..6x8  per  cent. 

Protein 36 

Fat 37 

Carbohydrates     ..  ..  ..         ..     300         „ 

Mineral  matters  ..  ..  ..  ..       09         „ 

and  has  a  fuel  value  of  about  780  Calories  per  pound  (Atwater).  It 
must  be  regarded  as  a  highly  nutritious  food. 

A  cupful  of  water-arrowroot  contains  only  about  30  grains  of 
starch.  It  would  furnish  to  the  body  about  9  Calories  of  fuel  value, 
while  even  an  invalid  requires  about  2,000  Calories  daily. 

When  one  considers  the  economy  of  these  different  preparations, 
one  may  say  that  tapioca  and  sago  are  worth  the  price  paid  for  them, 
while  the  better  qualities  of  arrowroot  certainly  are  not.  Starch  at 
4d.  a  pound  is  really  rather  dearer  than  tapioca  at  3d.  or  sago  at 
2d.,  even  although  it  contains  10  per  cent,  more  nutriment.  Apart 
altogether  from  that  also,  one  cannot  eat  pure  starch,  whereas  the 
same  chemical  substance  in  the  form  of  tapioca  or  sago  is  quite 
agreeable.  On  the  other  hand,  Bermuda  arrowroot  at  2s.  gd.,  or 
even  is.  6d.,  the  pound  is  a  purely  luxurious  article.  The  cheaper 
kinds  at  4d.  to  5|d.  are  quite  as  nutritious,  and  there  can  be  no 
physiological  objection  to  the  substitution  for  a  genuine  article  of 
the  so-called  Farina  or  English  arrowroot,  prepared  from  the  starch  of 
maize  or  potatoes,  at  3d.  per  pound.  Even  although  it  requires 
more  of  these  to  make  a  jelly  than  of  the  genitine  arrowroot,  yet  this 
diflFerence  is  far  more  than  made  up  for  by  the  difference  in  price. 


Ih8] 


CHAPTER  XIV 

VEGETABLES— FRUITS— NUTS— FUNGI— ALO-ffi  AND 
LICHENS 

Vegetables. 

The  leaves  of  green  vegetables  are  to  be  regarded  as  the  Ivings  of 
the  plant  to  which  they  belong.  They  are  merely  a  sort  of  frame- 
work on  which  the  green  colouring  matter,^  by  which  the  plant  feeds 
and  breathes,  is  spread  out.  In  no  sense  are  they,  like  the  roots, 
storehouses  of  reserve  nutriment.  One  would  not,  therefore,  expect 
that  such  leaves  would  have  high  nutritive  value,  and  chemical 
analysis  entirely  confirms  the  expectation.  Speaking  generally,  it 
may  be  said  that  green  vegetables  contain  a  great  deal  of  water, 
almost  no  nitrogenous  matter-  or  fat,  and  only  a  small  quantity  of 
carbohydrates  (2  to  8  per  cent.).  This  small  proportion  of  carbo- 
hydrates renders  their  use,  especially  as  carriers  of  fat,  admissible  in 
diabetes.  Their  framework  contains  a  good  deal  of  cellulose.  The 
amount  of  mineral  matter  which  they  contain  is  relatively  large, 
and  confers  upon  them  much  of  what  value  they  possess  as  foods. 

COMPOSITION  OF  VEGETABLES. 


Cabbage     . . 

,,  (cooked) 
Cauliflower  (head) 
Sea-kale 

(cooked)   . 
Spinach       . . 


Water. 

Nitro- 
genous 
Matter.3 

Fat. 

Carbo- 
hydrates. 

Mineral 
Matter. 

Cellu- 
lose. 

896 

18 

04 

3-8 

13 

II 

974 

0-6 

01 

04 

0  13 

13 

907 

2'2 

04 

47 

08 

1-2 

933 

14 

— 

3-8 

06 

09 

9795 

04 

0  07 

03 

02 

II 

90  6 

2'5 

05 

3-8 

17 

09 

Fuel 
Value 
per  lb. 

Calories. 
165 


*  Chlorophyll  itself  is  of  no  nutritive  value,  but  leaves  the  body  hardly  changed. 
'  Even  of  what  nitrogenous  matter  is  present  only  about  half  is  in  the  form  of 

protein. 

•  Probably  only  about  half  of  the  nitrogenous  matter  consists  of  protein. 


COMPOSITION  OF  VEGETABLES 
COMPOSITION  OF  VEGET ABIDES— continued. 


249 


Water. 

Nitro- 
genous 
Matter  ' 

Fat. 

Carbo- 
hydrates. 

Mineral 
Matter. 

Cellu- 
lose. 

Fuel 

Value 
per  lb. 

Calories 

Vegetable  marrow 

948 

■06 

02 

26 

05 

13 

Vegetable     marrow 

(cooked)  . . 

9917 

0  09 

004 

02 

005 

037 

Brussels  sprouts    . . 

937 

1-5 

01 

34 

1-3 

95 

Tomatoes    . . 

91  9 

13 

02 

50 

07 

II 

105 

,,        (cooked) 

9407 

10 

02 

01 

0  76 

15 

Greens 

829 

3-8 

09 

8-9 

35 

275 

Lettuce 

94"  I 

14 

04 

26 

10 

05 

105 

(cooked)    .. 

972 

05 

016 

05 

04 

09 

Leeks 

91-8 

1-2 

05 

5-8 

07 

— 

150 

Celery 

93  4 

14 

01 

33 

09 

09 

85 

(cooked) 

970 

03 

006 

08 

05 

10 

Turnip  cabbage     . . 

87-1 

26 

0  2 

71 

i"5 

13 

145 

Rhubarb     . . 

946 

07 

07 

23 

06 

II 

105 

Macedoine  (tinned) 

93  I 

i"4 

— 

45 

10 



no 

Watercress 

931 

07 

05 

37 

13 

07 

Cucumber  . . 

959 

08 

O'l 

21 

04 

05 

70 

(cooked) 

974 

05 

0  02 

07 

02 

09 

Asparagus^ . , 

91-7 

22 

02 

29 

09 

21 

no 

Salsify  (cooked)     . . 

872 

12 

008 

90 

03 

22 

Endives 

940 

10 

— 

30 

08 

06 

Savoys 

87  0 

33 

07 

60 

16 

12 

Red  cabbage 

90  0 

1-8 

019 

5-8 

07 

12 

Sauerkraut . . 

91  0 

14 

07 

28 

17 

09 

(acids 

1-26) 

OARSOHVORATE. 

CELLULOSE. 
MIN.  MAT 

CKTRACT 

Fig.  22. — Pbrcentage  Composition  of  a  Cabbage,  and  loss  of  bach 
Constituent  on  Boiling. 


*  Probably  only  about  half  of  the  nitrogenous  matter  consists  of  protein. 

"  Asparagus  contains  asparagio,  which  confers  upon  it  slight  diuretic  pro- 
perties. The  characteristic  odour  in  the  urine  which  follows  the  eating  of 
asparagus  is  due  to  a  volatile  sulphur  compound  which  is  produced  from  it  in 
the  intestine. 


250 


FOOD  AND  DIETETICS 


These  facts  regarding  the  composition  of  green  vegetables  will  be 
better  realized  by  a  study  of  Figs.  22  and  23.  The  former  represents 
the  composition  of  a  cabbage,  i.e,  a  typical  green  vegetable,  while 
the  latter  depicts  the  ingredients  of  a  cucumber,  which  is  a  type  of 
one  of  the  least  nutritive  of  this  class  of  foods. 

The  effect  of  cooking  upon  green  vegetables  is  still  further  to 
reduce  their  already  poor  stock  of  nutrients.  They  gain  water,  and 
lose  part  of  their  carbohydrate  and  protein,  much  of  their  mineral 


Fig.  23. — Percentage  Composition  of  a  Cdcdmber. 

matter,  and  nearly  the  whole  of  their  non-protein  nitrogenous  con- 
stituents. For  example,  a  cabbage  loses  by  boihng  30  per  cent,  of 
its  total  solids,  this  being  made  up  of  about  half  of  the  total  mineral 
matter,  one-third  of  the  carbohydrate,  the  whole  of  the  non  protein 
nitrogen,  and  5  to  10  per  cent,  of  the  protein  (see  Fig.  22). 

The  amount  of  water  gained  by  some  of  the  commoner  vegetables 
as  the  result  of  cooking  is  shown  in  the  following  table  :^ 

GAIN  OF  WATER  ON  COOKING  VEGETABLES. 


Parsnips 
Artichokes  . . 
Cabbage 
Spinach 
Cauliflower  . . 
Sea-kale 
Vegetable  marrow , 


Percent,  of 

Percent,  of 

Water  in 

Water  after 

Increase. 

Raw  State. 

Cooking. 

820 

972 

152 

800 

91  6 

II  6 

890 

975 

85 

900 

98'o 

80 

90  8 

964 

5-6 

93  3 

979 

46 

948 

99- 1 

43 

The  next  table  shows  the  amount  of  carbohydrate  contained  in 

some  of  the  commoner  vegetables,  and  (in  some  cases)  the  loss  on 

boiling  :* 

Raw 
(per  cent.). 


Cabbage  turnip  (young)    ..         ••         ,.     309 
Cauliflower..         ..         ..         ..         ..210 

Spinach        ..         297 

Winter  cabbage 675 

Asparagus — 

Savoys         ..         27 


After  Boiling 

and  Straining 

(per  cent.). 

243 
1-40 
085 
320 
I  6 


1  From  analyses  by  Katharine  J.  Williams,  Journ.  o/Chent.  Soc,  1892,  Ixi.  226. 
*  From  analyses  by  Kraus,  Zeii,  /.  Diat.  utid  Physik.  Therap.,  1898,  i.  69. 


EFFECTS  OF  COOKING  ON   VEGETABLES        251 

The  deficiency  of  fat  in  vegetables  is  often  made  up  by  the  addition 
of  butter  or  oil,  in  the  course  of  preparation  for  the  table.  Vegetables 
may  thus  be  made  an  important  vehicle  for  conveying  fat  into  the 
body.  The  proportion  of  fat  which  some  vegetables  can  take  up 
without  being  overloaded  is  as  follows  :^ 

100  parts  of  potato  pnr^e       can  take  up  ..  ..       50    parts  of  fat. 

boiled  potato  ,,         .,       ..  ..     40-50  „ 

baked        ,,  „         „       ..  ..         ,,  ,. 

red  cabbage  „         „       ..  ..40  „ 

savoy  cabbage  „         „       ..  ,.32  „ 

cabbage  lettuce     „         „       . .  . .       24  „ 

potato  souffle  „         „       ..  ..20  „ 

fried  potatoes  , . .       15  „ 

Vegetables,  as  a  whole,  are  not  easily  digested  by  the  stomach. 
Five  and  one-third  ounces  of  cabbage  require  three  hours.  Cauli- 
flower, it  is  worth  knowing,  is  much  the  most  easily  digested  of  all 
of  them.  Five  and  one-third  ounces  of  it  require  only  two  and  a 
quarter  hours. 

In  the  intestine  also  vegetables  are  difficult  to  deal  with.  The 
reason  for  this  is  their  bulk  and  the  amount  of  cellulose  which 
they  contain.  Gases  are  produced  by  the  action  of  organisms 
on  the  cellulose,  and  from  this  flatulence  is  apt  to  result. 
Fermentation  is  specially  apt  to  occur  when  the  vegetables  are  a 
little  stale.  To  be  wholesome  they  should  always  be  eaten  as  fresh 
as  possible. 

The  absorption  of  the  nutritive  constituents  of  most  vegetables  is 
also  rather  defective.  They  constitute  one  of  the  few  forms  of  food 
from  which  even  starch  is  not  completely  absorbed.  The  average 
waste  on  green  vegetables  is  approximately  as  follows  (Rubner): 

Dry  substance      ..     15*0  per  cent.  lost  I  Carbohydrates       ..     15-4  per  cent,  lost 
Protein      ..  ..      i8'o       ,,        ,,         |  Mineral  constituents    22'8       ,,         ,, 

When  one  realizes  that  green  vegetables  are  poor  in  nutrients  to 

start  with,  that  they  become  still  poorer  as  the  result  of  cooking, 

and  that  even  of  the  remnant  which  reaches  the  intestine  a  large 

part  escapes  absorption,  one  will  readily  understand  that,  considered 

as  foods,  they  are  of  very  low  nutritive  value.     Indeed,  it  may  be 

said  that  green  vegetables  are  only  of  use  in  the  diet  for  two  reasons. 

First,  they  supply  ballast  to  the  intestine ;  the  indigestible  residue 

which  they  leave  is  a  stimulus  to  the  intestinal  movements.      Hence 

their  special  value  in  constipation.     Secondly,  they  are  a  valuable 

source  of  mineral  salts.    The  most  abundant  of  these  are  compounds 

of  potash,  which  have  an  alkaline  reaction,  and  help  to  keep  the 

*  From  analyses  by  Kraus,  Zeit.  f.Didt.  und  Physik.  Therap.,  1898,  i.  69, 


252 


FOOD  AND  DIETETICS 


blood  supplied  with  alkali  and  to  lower  the  acidity  of  the  urine. 
It  is  probably  owing  to  their  richness  in  alkaline  salts  that  the 
use  of  green  vegetables  is  helpful  in  some  diseases  of  the  skin. 
Thus,  Clement  Dukes  points  out  that  he  has  several  times  seen 
epidemics  of  eczema  result  from  a  deficiency  of  green  vegetables 
in  the  diet  ('School  Diet,'  p.  103).  For  the  same  reason  the  free  use 
of  green  vegetables  should  be  recommended  to  patients  who  suffer 
from  gravel.  .Some  vegetables,  such  as  rhubarb,  contain  a  good  deal 
of  oxalic  acid.  These  should  be  avoided  in  cases  of  gravel.  The 
sour  taste  of  tomatoes  is  due  to  citric  acid,  not  to  oxalic,  as  is 
often  stated. \  Asparagus  and  onions  are  the  only  vegetables  which 
contain  appreciable  amounts  of  uric  acid-forming  bodies.  Green 
vege'ables  are  also  valuable  sources  of  iron  in  the  diet.  The  value 
of  the  mineral  ingredients  of  vegetables,  however,  will  be  dealt  with 
more  fully  in  a  subsequent  chapter.  Lastly,  it  must  be  mentioned 
that  green  vegetables  are  an  important  source  of  the  mysterious  sub- 
stances called  '  vitamines '  (p.  18).  It  is  to  the  presence  of  these  that 
the  curative  influence  of  fresh  vegetables  in  scurvy  is  due,  and  it  is 
probable  that  some  of  the  benefits  derived  from  their  use  in  health 
are  to  be  ascribed  to  the  same  cause. 


Fruits. 
The  fruit  is  not  of  direct  benefit  to  the  plant.     It  is  intended  as  a 
bait  to  attract  birds   or   insects,  and   so   insure  the   liberation  or 
transportation  of  the   seed.      Hence    the    aesthetic   qualities  pre- 


WATER. 


PROTEIN. 
EXTRACT. 
CARBOHYDRATE 
MIN.   MAT. 
CELLULOSE. 
ACIDS. 


Fig.  84.— Fercentage  Composition  of  a  Strawberry. 

dominate  in  fruit  rather  than  the  strictly  nutritive,  and  we  eat  them 
more  for  the  sake  of  their  sweetness  and  flavour  than  for  the  actual 
nourishment  which  they  afford. 


COMPOSITION  OF  FRUITS 
The  general  composition  of  fresh  fruit  is  something  like  this 


253 


Water 

Protein 

Fat 


85  to  90  per  cent,   i   Carbohydrates     . .   5i  to  lo^  per  cent, 
05  ,,  Cellulose   ..  . .   2^  ,, 

0-5  „  1  Mineral  matters  ..  0-5  ,, 


WATER. 


PROTEItl. 
FAT. 

CARBOHYDRATS. 
MIN     MAT. 
ACIDS. 
CELLULOSEl 


Fig.  25. — Percentage  Composition  of  an  ArrLE. 

The  composition  of  individual  members  of  the  group  is  shown  in 
the  following  table,  and  a  study  of  the  graphic  representation  of  some 
typical  fruits  will  illustrate  it  (Figs.  24,  25,  and  26). 


AVERAGE  COMPOSITION  OF  FRUITS  (EDIBLE  PORTION). 


Water. 

Protein. 

Ether 
Extract. 

Carbo- 
hydrates. 

Ash. 
04 

Cellu- 

lo-e. 

Acids. 

Apples 

82-5 

04 

05 

12-5 

27 

ID 

„      (dried) 

362 

1-4 

30 

491 

1-8 

4-9 

3-6 

Pears 

839 

04 

06 

"■5 

0-4 

3' I 

01 

Apricots 

85  0 

II 

? 

124 

0-5 

10 

Peaches 

88  8 

05 

02 

5-8 

06 

34 

07 

Greengages            , . 

So  8 

04 

— 

134 

03 

41 

10 

Plums 

78-4 

10 

? 

14-8 

0.5 

43 

10 

Nectarines  .. 

829 

06 

■> 

159 

06 

Cherries      . .         . . 

840 

0-8 

08 

100 

o'6 

3« 

10  to  15 

(Slulzer) 

Gooseberries 

860 

04 



8-9 

o'5 

27 

15 

Currants  (red,  black 

and  white) 

852 

04 

— 

79 

05 

46 

14 

Strawberries 

89-1 

10 

0-5 

6-3 

07 

22 

10  to  12 

Whortleberries     ( = 

Blaeberries  or  Bil- 

berries)    . . 

763 

07 

30 

58 

04 

122 

16 

Blackberries 

889 

09 

2-1 

23 

Ob 

52 

Raspberries 

844 

10 

? 

5-2 

06 

7-4 

1-4 

Cranberries            . . 

865 

05 

07 

3  9 

02 

62 

20  to  25 

Mulberries . . 

847 

03 

11  4 

06 

09 

18 

254 


FOOD  AND  DIETETICS 


AVERAGE  COMPOSITION  OF  FRUITS  (EDIBLE   PORTION)— 

continued. 


Water. 

Protein 

Ether 
Extract 

Carbo- 
hydrates. 

Ash. 

Cellu- 
lose. 

Acids. 

Grapes 

79 -o 

10 

i-o 

15-5 

0-5 

2-5 

0-5 

Melons 

89-8 

07 

03 

7-6 

06 

10 

Water-melons 

92  9 

03 

01 

6-5 

02 

Bananas    . . 

74  0 

15 

07 

22-9 

0-9 

0'2 

Oranges     . . 

867 

09 

0-6 

87 

0-6 

I '5 

10  to  25 

Orange-juice 

85-0 

— 

— 

IO-8 

— 

I  "93 

Lemons     . . 

^9-3 

10 

0-9 

8-3 

0-5 

Lemon-juice 

gt  0 

— 

2-0 

04 

70 

(citric  acid) 

Pineapples 

89-3 

0-4 

03 

97 

0-3 

Pomegranates 

768 

I '5 

I  6 

168 

0-6 

27 

Dates  (dried) 

20 -8 

4  "4 

21 

657 

I '5 

5-5 

Figs  (dried) 

20-0 

5 '5 

09 

62 -8 

23 

Ti 

1-2 

„     (fresh) 

79   I 

1-5 

— 

i8-8 

06 

Prunes  (dried) 

26-4 

24 

08 

66-2 

1-5 

— 

27 

(fresh)      .. 

802 

0-8 

p 

i8-5 

05 

Currants  (dried)  . . 

27  9 

1-2 

30 

64-0 

22 

17 

Raisins 

140 

25 

4-7 

747 

41 

Olives 

67  0 

2-5 

i-j-i 

5  7 

44 

yi 

Rhubarb  Stalks  . . 

94 '4 

06 

07 

25 

I  'I 

07 

The  composition  of  edible  parts  only  is  represented.     Where  cellulose  is  not 
given  it  is  included  with  carbohydrates. 

It  will  be  observed  that  the  only  nutritive  element  of  any  importance 
in  fruit  is  the  carbohydrate  group.  As  a  general  rule,  about  half  to 
three-quarters  of  the  total  carbohydrates  in  a  fruit  consist  of  sugar. 
The  particular  variety  is  that  known  as  fruit-sugar,  or,  in  chemical 
language,  laevulose ;  but  some  fruits,  e.g.,  apples,  apricots,  and  pine- 
apples, contain  a  considerable  amount  of  cane-sugar  as  well.  It  is 
of  some  importance  to  remember  this,  for  laevulose  is  certainly  more 
easily  assimilated  by  diabetics  than  other  sugars  are,  so  that  fruits 
may  often  be  allowed  in  mild  cases  of  that  disease  with  impunity. 
The  total  amount  of  sugar  contained  in  some  typical  fruits  is  shown 
in  the  following  table  :^ 


Hot-house  grapes 
Preserved       ,, 
Figs  (fresh) 
Cherries 
Preserved  pears 
Fresh  pears 
White  currants 
Strawberries 

The  remainder  of 


Total  Sugar 
{fer  cent.). 
.      1726 
.      1630 

•     11-55 

io"oo 

.       8  78 

.  7S4 
.  6"  40 
.       586 


Total  Sugar 

[per  cent.). 

Preserved  apjsles 

..    r,-25 

Raspberries 

••     7"23 

Oranges    . . 

..     8-58 

Apricots    . . 

..     878 

Pineapples 

..    1331 

Plums 

..     1-99 

Lemons    , . 

..     1-47 

the  carbohydrates   is   made  up   of  vegetable 
gums.     Many  of  these  seem  to  belong  to  that  group  of  '  pectin 
bodies  '  to  which  reference  has  already  been  made  (p.  163).     In  the 
*  Analyses  by  Buignet  (quoted  by  Konig). 


COMPOSITION  OF  FRUITS  255 

course  of  ripening,  some  of  them  seem  to  be  converted  into  the 
corresponding  sugar — pentose,  the  nutritive  value  of  which  must  be 
regarded  as  very  doubtful.  When  subjected  to  boiling,  the  gums  of 
many  fruits  yield  a  jelly,  the  production  of  which  is  familiar  in  the 
process  of  making  preserves. 

The  amount  of  cellulose  varies  greatly  in  different  fruits.  It  is 
always  lessened  by  the  process  of  cultivation — witness  the  difference 
between  a  crab  apple  and  a  Newtown  pippin — and  it  diminishes 
also,  by  a  sort  of  natural  digestion,  during  the  ripening  of  the 
fruit. 

The  mineral  constituents  of  fruits  are  of  considerable  importance. 
They  consist  mainly  of  potash  united  with  various  vegetable  acids, 
such  as  tartaric,  citric,  and  malic.  These  have  an  agreeable  acid 
flavour,  but  when  burnt  up  inside  the  body  are  converted  into  the 
corresponding  carbonate,  and  so  help  to  render  the  blood  more 
alkaline  and  the  urine  less  acid.  Thus,  i  fluid  ounce  of  lemon- 
juice  contains  45  grains  of  citric  acid  and  saturates  45|-  grains  of 
bicarbonate  of  soda.  As  the  fruit  ripens,  these  vegetable  acids 
diminish  to  some  extent,  and  it  is  to  this  fact,  coupled  with  an 
increase  in  the  amount  of  sugar  present,  that  the  sweetness  of  ripe 
as  compared  with  unripe  fruit  is  due.  The  earthy  salts  are  but 
poorly  represented  among  the  mineral  ingredients  of  fruits,  and 
for  this  reason  the  free  use  of  fruit  in  place  of  cereals  has 
been  recommended  by  some  writers  to  persons  suffering  from 
atheroma. 

The  odour  and  flavour  of  fruits  are  due  to  the  presence  of  very 
small  quantities  of  ethereal  bodies  which  sometimes  elude  chemical 
investigation.  In  many  cases,  however,  we  have  been  able  to 
obtain  (from  coal-tar,  too,  of  all  sources)  artificial  products  which 
have  precisely  the  same  flavour  as  many  fruits.  These  products 
form  the  basis  of  the  different  fruit  flavourings  and  essences  sold 
in  the  shops.  Although  of  no  nutritive  value,  the  flavouring  sub- 
stances contained  in  fruits  are  by  no  means  to  be  despised  as  stimu- 
lants to  the  appetite  and  aids  to  digestion. 

Cooking  renders  most  fruits  more  digestible  by  softening  their 
cellulose,  and  it  also,  as  we  have  seen,  converts  the  gums  into  a 
gelatin Dus  form.  But  these  changes  are  not  brought  about  without 
a  good  deal  of  loss.  The  loss  affects  all  the  ingredients  of  the  fruit. 
The  following  instances  show  the  exact  figures  for  the  carbo- 
hydrates :  * 

•  From  analyses  by  Kraus,  Zeit.  f.  Didt.  u.  Physik.  Therap.,  1898,  i.  69. 


256  FOOD  AND  DIETETICS 


Raw  apples 

11-7  per  cent. 

Pears  once  boiled     . 

.  6'6  per  cent 

Apples  once  boiled 

7-3 

,,      twice     ,, 

59 

twice     ,, 

61         „ 

Raw  peaches 

95 

Raw  pears    . . 

lo-i 

Peaches  once  boiled 

1-8         „ 

Where,  as  is  usually  the  case,  the  fruit  is  cooked  by  stewing  and 
the  juice  eaten  along  with  it,  this  effect  of  cooking  is  of  no  moment. 

The  digestibility  of  fruit  in  the  stomach  and  intestine  is  dependent 
largely  on  the  nature  of  the  fruit  and  its  degree  of  ripeness.  Five  and  a 
third  ounces  of  raw  ripe  apple  (one  large  or  two  small  apples)  require 
about  three  hours  and  ten  minutes  for  its  digestion  by  the  stomach. 
On  the  other  hand,  if  the  fruit  be  unripe  and  the  amount  of  cellulose 
consequently  greater,  digestion  may  be  much  more  prolonged.  The 
excess  of  acids  present  in  unripe  fruit  causes  the  latter  to  be  irritating 
to  the  intestine,  and  a  frequent  originator  of  diarrhoea  and  colic.  If, 
however,  the  cellulose  and  acids  are  contained  in  more  moderate 
quantity,  as  in  ripe  fruit,  the  gentle  stimulation  which  they  exert  on 
the  intestinal  wall  may  be  very  useful.  Hence  it  is  that  stewed 
fruit  is  so  serviceable  an  addition  to  the  diet  in  sluggish  action  of 
the  bowels. 

There  have  been  few  experiments  made  to  test  the  degree  to 
which  fruit  is  absorbed  by  the  human  intestine,  but  one  may 
expect  that  the  protein  will  be  absorbed  to  about  go  per  cent, 
the  fats  to  85  per  cent.,  and  the  carbohydrates  to  95  per  cent.,  if 
the  conditions  be  reasonably  favourable. 

From  a  nutritive  point  of  view  fruits  may  be  artificially  divided 
into  the  two  groups  of  flavour-fruits  and  food-fruits.  In  the  former 
one  would  include  all  fruits  which  contain  more  than  80  per  cent,  of 
water ;  in  the  latter,  all  fruits  or  fruit  preparations  which  have  more 
than  20  per  cent,  of  solids. 

The  only  claim  of  the  members  of  the  first  group  to  be  regarded 
as  foods  is  that  they  contain  a  small  amount  of  sugar  in  a  pleasant 
but  rather  bulky  form.  They  are  chiefly  eaten  for  the  sake  of  their 
pleasant  flavour.  Their  richness  in  water  makes  them  more  adapted 
to  the  requirements  of  the  inhabitants  of  warm  countries  than  for 
use  in  northerly  latitudes,  and  one  finds  that  if  they  are  freely 
represented  in  the  diet  less  water  requires  to  be  consumed. 

Grapes  stand  intermediate  between  the  two  groups,  for  their  juice 
contains  an  amount  of  sugar  which  varies  from  10  per  cent,  in  the 
poorer  up  to  30  per  cent,  in  the  richer  varieties.  In  the  so-called 
grape-cure,  from  i  to  8  pounds  of  grapes  are  taken  daily  in  divided 
quantities,  and  between  meals.  If  the  rest  of  the  diet  is  sufl&cient, 
the  patient  may  gain  weight  on  this  regimen,  while  the  grape-juice, 


THE  BANANA 


257 


owing  mainly  to  the  organic  acids  which  it  contains,  acts  as  a  mild 
laxative  and  diuretic,  and  at  the  same  time  diminishes  slightly  the 
acidity  of  the  urine.  In  this,  as  in  all  similar  'treatments,'  much 
of  the  credit  of  the  results  attained  must  be  put  down  to  the  circum- 
stances under  which  the  '  cure '  is  carried  out,  for  the  patient  is 
expected  to  gather  the  grapes  for  himself,  and  doing  this  entails  a 
certain  amount  of  exercise  in  the  fresh  air.  It  is  chiefly  in  cases  of 
so-called  'abdominal  plethora,'  i.e.,  the  results  of  habitually  eating 
too  much  and  taking  too  little  exercise,  that  benefit  has  been 
observed  from  such  a  course  of  treatment,  but  it  is  also  useful  in 
some  cases  of  chronic  bronchial  catarrh. 

Mostelle  is  an  unfermented  grape-juice 
preserved  by  pasteurization.  It  contains 
about  25  per  cent,  of  grape-sugar,  and 
is  a  useful  food -beverage,  especially  in 
fevers. 

The  food-fruits,  on  the  other  hand, 
are  not  to  be  despised  as  sources  of  real 
nutriment.  Of  this  group  the  banana 
is  a  good  example.  In  the  fresh  state 
this  fruit  contains  a  fair  amount  of  car- 
bohydrate and  an  appreciable  amount 
of  protein  as  well,  while  bananas  dried 
in  the  sun  and  sprinkled  with  sugar,  a 
form  in  which  they  have  recently  been 
imported,  compare  favourably  with 
dried  figs  in  nutritive  value,  and  are 
a  pleasant  substitute  for  the  latter  at 
dessert. 

In  its  ordinary  form,  however,  the  Fig.  26.— Percentage  Compo- 
banana  is  too  bulky  to  be  able  to  serve  '°^  °    '^    anana. 

as  the  main  constituent  of  a  healthy  diet.  Assuming  that  an 
average  sized  specimen  weighs  45  grammes  or  if  ounces  (without 
the  husk),  it  would  require  about  eighty  of  these  to  yield  the 
amount  of  energy  required  daily,  and  nearly  double  that  number  to 
supply  the  requisite  amount  of  protein .1  No  wonder,  then,  that 
in  tropical  countries,  where  the  banana  is  largely  eaten,  the  inhabit- 
ants are  apt  to  show  an  undue  abdominal  development. 

1  These  quantities  have  been  calculated  from  European  dietary  standards,  and 
represent  the  amount  of  energy  and  protein  required  by  a  man  in  this  country. 
On  the  Gold  Coast,  however,  as  Mr.  C.  G.  Moore  informs  me,  the  natives  eat 
about  eight  plantains  (the  equivalent  of  about  sixteen  bananas)  daily,  supple- 
mented occasionally  by  a  little  dried  fish,  and  on  this  diet  they  manage  to 
perform  a  fair  amount  of  work. 

»7 


CARBOHYDRATE 


MIN.   MAT. 
CELLULOSE 


258  FOOD  AND  DIETETICS 

The  unripe  banana  is  dried  and  used  to  produce  banana  meal  or 
flour.     A  sample  of  such  a  flour  had  the  following  composition  : 

Banana  Flour.  Wheat  Flour. 

Moisture  130  per  cent.  13-8  per  cent. 

Protein 4'o         ..  7'9 

Fat  0-5         „  14         ,, 

Carbohydrates 80 -o         „  76-4         „ 

Mineral  matter  ..         ..       2*5        ,.  05        „ 

I  have  placed  alongside  of  it  the  composition  of  good  wheat 
flour,  compared  with  which  the  banana-meal  is  rich  in  carbo- 
hydrates and  mineral  matter,  but  very  poor  in  protein.  If  rice, 
on  the  other  hand,  had  been  taken  for  comparison,  it  would  have 
been  found  that   banana  flour  was   about  equal  to  it   in    nutritive 

value. 

Eananina  is  a  proprietary  food  obtained  from  the  banana  by  a 
special  process  after  the  fibrous  matter  has  been  extracted,  and  is 
designed  for  the  use  of  infants  and  invalids.  For  an  analysis  of 
it,  see  p.  469.  It  consists  chiefly  of  starch,  but  is  stated  to  be 
easily  digested. 

Banana  flour  can  be  used  to  make  a  sort  of  bread,  and  it  is  said 
to  be  easy  of  digestion.  Two  pounds  of  such  flour  and  a  quarter  of 
a  pound  of  salt  meat  or  fish  is  stated  to  form  the  daily  allowance  for 
a  labourer  in  tropical  America  (Johnston). 

Another  advantage  of  tlie  banana  is  the  cheapness  with  which  it 
can  be  produced.  A  given  area  of  ground  devoted  to  its  cultivation 
will  yield  a  larger  food  return  than  in  any  other  form,  unless  it  be 
planted  with  chestnut-trees. 

'A  spot  of  a  little  more  than  1,000  square  feet  will  contain  from 
thirty  to  forty  banana  plants.  A  cluster  of  bananas  produced  on  a 
single  plant  often  contains  from  i6o  to  180  fruits,  and  weighs  from 
70  to  80  pounds.  But  reckoning  the  weight  of  a  cluster  only  at 
40  pounds,  such  a  plantation  would  produce  more  than  4,000  pounds 
of  nutritive  substance.  M.  Humboldt  calculates  that  as  33  pounds 
of  wheat  and  99  pounds  of  potatoes  require  the  same  space  as  that 
in  which  4,000  pounds  of  bananas  are  grown,  the  produce  of  bananas 
is  consequently  to  that  of  wheat  as  133:1,  and  to  that  of  potatoes 
as  44:  I.  .  .  .  A  much  greater  number  of  individuals  may  be  sup- 
ported on  the  produce  of  a  piece  of  ground  planted  with  bananas, 
compared  with  a  piece  the  same  size  in  Europe  growing  wheat. 
Humboldt  estimates  the  proportion  as  25  to  i  ;  and  he  illustrates 
the  fact  by  remarking  that  a  European,  newly  arrived  in  the  torrid 
ssone,  is  struck  with  nothing  so  much  as  the  smallness  of  the  spots 


NUTS 


259 


under  cultivation  round  a  cabin  which  contains  a  numerous  family 
of  Indians '  (Knight). 

It  is  evident  from  this  that  we  possess  in  the  banana  a  potential 
source  of  cheap  nourishment  which  may  one  day  be  of  great 
importance. 

Surpassing  even  the  banana  in  nutritive  value  is  the  group  of 
dried  fruits,  which  includes  such  examples  as  the  date  and  the 
raisin.  The  former,  indeed,  is  as  much  a  staple  article  of  diet  to 
the  Egyptian  as  rice  is  to  the  Hindu,  but  the  carbohydrate  of  rice 
is  mainly  in  the  form  of  starch,  whereas  in  the  date  it  is  almost 
solely  present  as  sugar.  '  A  half-pound  of  dates  and  half  a  pint  of 
milk  makes  an  ample  and  satisfying  meal  for  a  person  engaged  in 
sedentary  labour '  (Densmore). 

The  fig  is  another  valuable  member  of  this  group.  Dried  figs 
contain  about  50  per  cent,  of  sugar  and  3-5  per.  cent,  of  protein. 
Weight  for  weight,  they  are  more  nourishing  than  bread,  and  a  pint 
of  milk  and  6  ounces  of  dried  figs  makes  a  good  meal.  One  and  a  half 
pounds  of  them  yield  400  grammes  of  carbohydrate,  or  four-fifths  of 
the  total  amount  of  that  nutritive  ingredient  required  daily. 

AVERAGE  COMPOSITION  OF  DRIED  FRUITS  (EDIBLE  PORTION). 


Water. 

Protein, 

Ether 
Extract. 

CarVjo- 
hydrales. 

Cellu- 
lose. 

A^h. 

Calorie 

Value 

per  Pound. 

Dates         

Figs 

I5'4 

18-8 

56-5 
22-3 

76-6 
14-6 

2'I 

12 
2*1 

05 

2-6 

2-8 

0-3 
01 

33 

74  "6 

6S0 

3-8 
6-2 

1-3 

24 

i*i 
23 

05 
3*4 

1,615 
1.475 

,,      (stewed 
Prunes 

40-9 
71-2       1      2-1 

785 

1,400 

(stewed)    .. 
Raisins 

22-3 

73  6     1     25 

430 

1,605 

Nuts. 


Nuts  differ  very  markedly  from  the  fruits  which  we  have  been 
considering,  in  that  they  are  of  very  high  nutritive  value.  Bulk  for 
bulk,  indeed,  dry  nuts  are  amongst  the  most  nutritive  foods  which 
we  possess.     Their  general  composition  is  roughly  as  follows : 


Water 

,, 

4  to    5  per  cent. 

Carbohydrates 

9  to  12  per 

Protein 

, , 

15  ,,  20         ,, 

Cellulose 

3  „    5 

Fat      .. 

•  • 

50  .,  60         „ 

Mineral  matter 

I  per  cent. 

26o 


FOOD  AND  DIETETICS 


CARBOHYDRATC 
MIN.  MAT 


CELLULOSE. 


Fig.  27. 


-Percentage  Composition 
or  A  Walndt. 


A  graphic  representation  of  a  typical  specimen  of  the  group,  the 

walnut,  is  shown  in  Fig.  27. 

It  will  be  observed  that  fatty 
matter  predominates  very  largely 
in  the  composition  of  nuts.  No 
other  vegetable  substance  is  so 
rich  in  fats  as  these.  Advantage 
has  been  taken  of  this  to  prepare 
from  nuts  various  fatty  prepara- 
tions which  are  used  as  cheap  and 
eflicient  substitutes  for  ordinary 
butter  in  the  kitchen.  Amongst 
these  are  the  commercial  prepara- 
tions known  as  *Albene,'  '  Nuco- 
line,'  '  Vegsu,*  or  '  vegetable  suet,' 
•  Nut  Butter '  and  '  Nuttolene,' 
also  '  Cocos  Butter,'  '  Cocoleum,' 
and  '  Cocolardo.'  There  is  every  reason  to  believe  that  these  are 
equal  in  nutritive  value  to  ordinary  butter,  whilst  they  are  decidedly 
more  economical.  '  Albene '  costs  gd.  per  pound,  and  10  ounces  of 
it  are  said  to  go  as  far  as  i  pound  of  butter.  '  Nucoline  '  costs  6d. 
per  pound,  and  4  pounds  of  it  are  stated  to  be  equivalent  in  cooking 
operations  to  6  pounds  of  butter.  '  Nut  Butter '  and  '  Nuttolene ' 
contain  protein  as  well  as  fat,  and  are  therefore  to  be  compared  to 
cream  rather  than  to  ordinary  butter. 

Unfortunately,  nuts  are  not  readily  digested  in  the  stomach. 
This  is  due  in  part  to  their  richness  in  fat,  and  partly  also  to 
their  containing  a  high  proportion  of  cellulose,  which  forms  a  dense 
and  compact  framework  throughout  the  structure  of  the  nut.  By 
thorough  mastication,  the  latter  difficulty  can  be  overcome  to  some 
extent,  but  it  is  still  more  efficiently  dealt  with  by  artificial  grinding 
and  cooking.  Various  preparations  derived  from  nuts,  in  which  this 
mechanical  cause  of  difficulty  in  their  digestion  has  been  to  a  large 
extent  overcome,  are  now  in  the  market.  Best  known  of  these  are 
the  '  Fromm's  Extract,*  and  the  various  preparations  of  the  Sanitas 
Nut  Food  Co.  (•  Nuttose,' '  Bromose,'  'Nutmeal,'  and  '  Malted  Nuts,' 
etc.). 

Fromm's  Extract  consists  of  nuts  which  have  been  crushed,  and 
from  which  the  excess  of  cellulose  and  oil  have  been  removed.  The 
preparation  is  then  cooked  under  special  conditions,  which  develops 
in  it  a  flavour  not  unlike  that  of  meat.  It  has  the  following 
composition  : 


NUTS  261 

FROMM'S  EXTRACT. 


Water 

,.  25-3  percent. 

Carbohydrates   and 

Protein 

••    21*9           ,, 

cellulose 

8-3  per  cent 

Fat  .. 

..  31-6        „ 

Mineral  matter 

12-8 

There  can  be  no  doubt  that  this  is  a  preparation  of  high  nutritive 
value.     It  costs,  however,  3s.  6d.  per  pound. 
The  following  is  the  composition  of  malted  nuts  : 


Water 

. .     45  per  cent. 

Maltose 

. .   49*3  per  cent 

Protein 

•  •  23-6 

Mineral  matter 

22         ,, 

Fat    .. 

•  .     20"4 

But  few  experiments  have  been  made  on  the  absorbability  of  nuts. 
In  one  which  was  carried  out  in  America,^  and  in  which  the  subject 
of  experiment  lived  solely  on  a  diet  of  fruit  and  nuts,  it  was  found 
that  82*5  per  cent,  of  the  protein,  86-9  per  cent,  of  the  fat,  and 
96  per  cent,  of  the  non-nitrogenous  matters  were  absorbed.  This 
result  compares  favourably  with  the  absorption  of  an  ordinary  njixed 
diet  except  that  it  shows  a  rather  greater  waste  of  protein,  and  shows 
that  it  is  quite  possible,  for  long  periods  at  any  rate,  to  supply  the 
requisite  protein  and  energy  from  a  diet  made  up  of  selected  fruits 
and  nuts. 

The  nutritive  vahie  of  nuts  is  no  doubt  extremely  high,  and  when 
suitably  prepared  they  may  form  substitutes  for  meat  to  a  consider- 
able extent,  for  they  resemble  the  latter  in  containing  much  protein 
and  fat  in  small  bulk.  They  are  an  even  more  concentrated  food 
than  cheese,  and  should  rather  be  used  as  part  of  the  ordinary  diet 
than  as  a  supplement  to  an  otherwise  large  meal.  Thirty  large 
walnuts  (weighing,  without  the  shells,  100  grammes)  would  contain 
as  much  fat  as  2f  pounds  of  moderately  lean  beef,  but  2|  ounces 
of  such  beef  would  be  equal  to  them  in  protein.  It  would  be 
necessary  to  consume  about  700  walnuts  in  order  to  obtain  the 
necessary  amount  of  protein  required  by  the  body  every  day. 

A  cocoanut  weighing  i^  pounds  contains  \  pound  of  fat.  Its 
price  is  about  2d.,  so  that  as  a  source  of  fat  it  is  equivalent  to  butter 
at  8d.  the  pound. 

Of  all  the  members  of  this  class  of  foods,  the  chestnut  is  probably 
of  the  greatest  general  value  as  an  article  of  diet.  This  is  due  to  its 
containing  a  high  proportion  of  carbohydrates  along  with  much  pro- 
tein and  fat,  as  is  shown  in  the  following  recent  analyses  : 

1  'Nutrition  Investigations  among  Fruitarians  and  Chinese,'  U.S.  Department 
of  Agriculture,  Office  of  Experiment  Stations,  Bull.  No.  107,  1901.  For  more 
recent  experiments,  which,  however,  yielded  substantially  the  same  results,  see 
'  Nuts  and  their  Uses  as  Foods,'  Farmers'  Bull.  No.  332,  1908. 


262 


FOOD  AND  DIETETICS 


COMPOSITION  OF  CHESTNUTS.^ 


HiiO. 

N 
Matter. 

Fat. 

Carbo- 
hydrates. 

Cellulose. 

Ash. 

Acidity. 

Mini-  f  Normal 
mum    I  Dried  . . 
Maxi-  i  Normal 
mum   1  Dried  . . 

5280 
000 

62  60 
000 

201 

445 

431 

11  05 

045 

117 

173 
3-74 

3154 

8217 
4074 
88  61 

074 
I  76 
136 
329 

057 
1-24 
122 
306 

0059 
0164 

Roasted  chestnuts  have  40  per  cent,  water.  Those  cooked  by  boiling  have 
72  per  cent. 

An  economic  point  in  favour  of  chestnuts  also  is  the  fact  that  a 
given  area  of  ground  produces  the  maximum  amount  of  human  food 
when  planted  with  chestnut-trees. 

The  great  value  of  the  chestnut  has  been  fully  recognised  by  the 
poorer  peasantry  of  Central  France.  During  the  autumn  and  winter 
they  often  make  two  meals  a  day  from  it  alone.  The  nuts  are  pre- 
pared by  removing  the  outside  shell,  blanching,  and  then  steaming ; 
salt  and  milk  are  added  when  they  are  eaten.  Sometimes  they  are 
ground  after  blanching,  and  the  meal  made  into  flat  cakes. 

The  almond  is  another  very  valuable  form  of  nut,  being  specially 
noteworthy  for  the  large  amount  of  nitrogenous  matter  which  it 
contains.  It  has  the  further  advantage  of  being  compact  and 
portable.  'No  man,'  it  has  been  said,  'need  starve  on  a  journey 
who  can  fill  his  waistcoat  pocket  with  almonds.' 

Owing  to  its  poverty  in  carbohydrates,  the  almond  is  largely 
employed  in  the  manufacture  of  diabetic  breads.  The  detailed 
composition  of  the  commoner  varieties  of  nuts  is  exhibited  in  the 
following  table : 

COMPOSITION  OF  NUTS  (EDIBLE  PORTION) 


Water. 

Protein. 

Fat. 

Carbo- 
hydrates 

Cellu- 
lose. 

Mineral 
Matter. 

Chestnuts  (fresh) 

38-5 

6-6 

80 

45-2 

17 

(dried) 

5-« 

101 

100 

71 '4 

27 

Walnuts  (fresh) 

44  "5 

I2-0 

3it) 

9-4 

0-8 

17 

(dried) 

4b 

1.5-6 

626 

74 

..         7-8 

2-0 

Filberts  and  hazels  (fresh)     . . 

480 

80 

285 

II-5 

2-5 

15 

(dried)     .. 

37 

14-9 

664 

97 

32 

1-8 

Sweet  almonds 

60 

240 

54 'o 

lo-o 

3-0 

30 

Pistachio  kernels 

74 

217 

5I-I 

I4'0 

3-5 

33 

Cocsanut  (fleshy  part) 

46-6 

52 

359 

8-4 

29 

I'D 

(dri»d) 

3-5 

6-0 

^74 

31-8 

i"3 

(milk) 

903 

05 

— 

9-0 

— 

Hickory  nuts 

60 

150 

65-0 

120 

2'0 

Brazil  nuts        

50 

i7'o 

67-2 

7-0 

4-0 

Pea  nuts  (kernels) 

9*3 

27-9 

42*0 

187 

2-1 

»  Balland,  ref.  Analyst,  1897,  p.  216. 


FUNGI  263 

FungL 

The  edible  fungi  are  popularly  spoken  of  as  mnshrooma,  and  the 
inedible  ones  as  toadstools.  There  is  really,  however,  no  such 
division,  lor  all  the  larger  fleshy  fungi  are  toadstools,  and  probably 
most  of  them  are  edible.  The  v/ord  '  mushroom  '  has  therefore  only 
the  practical  convenience  of  distinguishing  the  best-known  edible 
fungi  met  with  in  commerce. 

There  are  about  1,400  species  of  toadstools  met  with  in  this 
country,  and  of  these  about  a  hundred  are  known  to  be  edible,  while 
not  more  than  thirty  have  been  definitely  proved  to  be  poiscLUOus. 
There  are  probably  a  great  many  more  edible  varieties,  but  the  only 
way  of  finding  out  whether  they  are  so  or  not  is  by  trying — a  mode 
of  experiment  which  is  somewhat  risky.  But  our  ignorance  in  this 
respect  need  not  be  a  matter  of  regret,  for  even  although  many  more 
toadstools  should  be  found  to  be  harmless,  yet  they  are  probably  not 
worth  the  eating. 

The  poisonous  properties  of  fungi  are  due  to  the  presence  in  them 
of  alkaloids.  The  nature  of  these  differs  in  the  different  species,  so 
that  the  symptoms  of  toadstool-poisoning  are  varied.  The  genus 
Amanita,  most  of  which  are  very  dangerous,  contains  an  alkaloid 
'  Amanita  toxin, '^  which  acts  as  an  irritant  to  the  stomach  and 
bowels,  and  also  paralyzes  the  nervous  system.  This  poison  is 
peculiar  in  that  it  does  not  exert  its  effects  for  some  hours  after  the 
fungus  has  been  swallowed,  so  that  at  first  the  patient  feels  perfectly 
well.  It  is,  however,  extremely  potent,  so  that  a  very  small  portion 
of  such  a  fungus  may  prove  fatal.  The  alkaloid  found  in  the 
poisonous  examples  of  Russula  and  Lactarius  is  purely  irritant  in  its 
effects,  and  induces  vomiting  and  diarrhoea,  thus  leading  to  the 
discharge  of  the  fungus,  and  bringing  about  its  own  cure.  The 
symptoms,  too,  follow  immediately  upon  the  eating  of  the  fungus, 
and  without  any  delay.  The  Agaricus  muscarius  contains  the  alkaloid 
muscarin,  which  produces  symptoms  very  much  resembling  those  of 
cholera.     The  Czar  Alexis  lost  his  life  by  eating  it. 

It  is  not  easy  to  lay  down  definite  rules  for  the  recognition  of  the 
harmless  fungi,  while,  unfortunately,  some  of  the  most  dangerous  are 
also  those  of  commonest  growth.  Certain  general  indications  it  is 
always  safe  to  observe.  Thus,  all  fungi  should  be  avoided  when 
they  are  overripe,  or  when  they  have  been  attacked  by  slugs. 
Those  that  soften  easily  are  usually  dangerous,  and  the  same  is  true 
of  fimgi  which  grow  in  dirty  situations,  such  as  dunghills,  for  this 

'  See  Ford  ('A  Consideration  of  the  Poisons  of  Amanita  Phalloides '),  Bn'^, 
lied.  Journ.,  1906,  ii.  1541. 


264  FOOD  AND  DIETETICS 

plant  has  a  great  tendency  to  absorb  poisons  from  the  medium  Oh 
which  it  happens  to  be  growing.  Lastly,  all  those  which  have 
a  disagreeable  smell  or  taste  should  certainly  be  rejected. 

The  fungus- eater's  safest  ground  is  unquestionably  amongst  the 
Boletus  family.  The  distinguishing  mark  of  these  fungi,  as  opposed 
to  the  Agarici  is  that  they  have  tubes  under  the  cap  instead  of  gills 
Of  the  forty-nine  native  species  of  this  family,  most  are  edible,  and 
many  quite  excellent.  But  there  are  exceptions,  one  or  two 
members  being  virulently  poisonous.  There  need  not,  however,  be 
any  difficulty  in  distinguishing  these,  for  all  the  safe  ones  are 
characterized  by  being  yellow  beneath  the  cap.  To  this  rule  there 
is  only  one  exception,  and  it  is  easily  told  by  its  scarlet  stem.  All 
those  that  are  red  or  pink  or  orange  or  brown  beneath  the  cap  should 
be  avoided.  It  is  well  also  to  discard  all  those  which  change  colour 
on  cutting  or  bruising. 

The  Boletus  edulis  occurs  abundantly  in  beech  woods,  especially 
in  the  South  of  England.  It  has  a  light  brown  cap,  the  under  part 
of  which  is  first  white  and  then  yellow-green,  vnth  a  thickish  pale 
brown  stem,  surmounted  by  a  fine  white  network.  This  network  is 
the  best  feature  by  which  to  distinguish  it  from  its  congeners.  It  is 
in  best  edible  condition  when  the  under  surface  is  yellowish. 

Belonging  to  a  different  family  (the  Hydnei,  or  teeth-bearing 
fungi)  is  the  Hydnum  repandum — the  urchin  of  the  wood.  It  is  of  a 
buff  white  colour,  and  is  easily  recognised  by  the  long  unequal  spines 
beneath  its  cap.  It  is  amongst  the  most  delicate  of  toadstools, 
having  a  slight  flavour  of  oysters.  It  is  best  in  the  young  and  fresh 
state,  and  is  largely  employed  as  food  in  Belgium,  Austria,  and 
France.  The  Agaricus  family  includes  a  large  number  of  edible 
fungi,  the  best  known  of  which  is  the  common  mushroom  {Agaricus 
campestris).  Another  favourite  is  the  Agaricus  gambosus,  or  St. 
George's  mushroom,  which  is  found  in  spring  and  early  sum.mer, 
growing  on  downs  and  pastures,  often  in  immense  fairy-rings.  Its 
stem  is  stout  and  solid,  and  the  gills  yellowish -white  and  much 
crowded  together.  It  has  a  strong  odour  of  fresh  meat,  which  is  so 
powerful  that  workmen  employed  to  root  out  the  fungus  are  said  to 
have  been  so  overcome  by  the  odour  as  to  be  compelled  to  desist 
(Cook).     It  is  better  eating  than  the  common  mushroom. 

One  of  the  best  of  all  is  the  Paxillus  giganteus,  which  is  found  in 
August  and  September.  It  is  firm  in  texture  and  of  a  dingy  white 
colour  with  yellow  stains  on  the  stem.  It  is  easily  identified  by  its 
fine,  creamy  white  gills  and  its  broad  inrolled  disc. 

The  Lactarius  deliciosus  and  the  Cantharellus  Cibarius  (chantrelle) 


COMPOSITION  OF  FUNGI 


265 


belong  to  different  groups.  The  former,  as  its  name  implies,  is  one 
of  the  nicest  of  all  edible  fungi.  It  is  not  difficult  to  recognise,  but 
is  apt  to  be  attacked  by  a  reddish  parasitic  fungus,  and  in  that  state 
is  dangerous.  It  is  of  an  orange  colour  with  a  yellowish,  milky  juice, 
and  grows  abundantly  in  fir  plantations.  The  chantrelle  is  found  in 
large  numbers  in  most  of  our  woods  in  autumn.  It  is  orange  yellow 
both  within  and  without,  and  has  a  pleasant  smell  of  ripe  apricots. 
It  has  a  delightful  flavour,  and  one  writer  goes  the  length  of  saying 
that  if  properly  prepared  '  it  would  arrest  the  pangs  of  death  !' 

The  common  morel  {Morchella  escuknia)  and  the  truffle  (Tuber 
cibarium)  are  both  much  -  prized  fungi.  The  former  grows  in 
England,  but  is  usually  imported  from  abroad  in  a  dried  state,  and 
fetches  a  high  price.  The  truffle  is  an  underground  fungus  which 
grows  in  dry  soils.  In  England  it  is  chiefly  found  in  Wiltshire, 
Hampshire,  and  Kent.  The  black  variety  is  most  esteemed.  Both 
morels  and  truffles  are  chiefly  valued  for  their  delicate  flavour,  and 
are  common  constituents  of  seasonings  and  sauces.  Though  usually 
eaten  dried,  they  are  very  much  better  when  fresh. 

The  chemical  composition  of  the  commoner  edible  fungi  is  shown 
in  the  following  table  : 

COMPOSITION  OF  FUNGI.» 


Mushroom 
{Agaricus 
campestyis). 

Chantrelle 
(Caw  tha- 

reiius 
cibartus). 

Truffle 

(  Tuber 

cibarium). 

Edible 
Boletus 
{Boietui 
tdulis). 

Lactetriu* 
deiicitsut. 

Moisture            ,.         .. 

937 

9093 

730 

8419 

8908 

Amides,  etc 

13 

064 

14 

26 

091 

Proteins 

22 

I  19 

61 

37 

1-88 

Fat           

03 

064 

06 

04 

054 

Carbohydrates  .. 

1-2 

509 

6  02 

465 

449 

Cellulose 

II 

033 

6-4 

074 

032 

Mineral  matter . . 

03 

I  20 

20 

The  following  ana 

ysis  of  i 

le  solids 

and  nitr 

Dgenous 

matter  in 

tinned  French  mushrooms  is  given  by  Saltet :  * 


Dry  Substance. 

Total 

Nitrogen. 

Percenttss  of 
N  in  Dry 
Substance. 

Proportion  of 

the  Total  N 

present. 

Mushrooms     . . 
Fluid  in  tin     . . 

3784 

8  91 

27  , 
048' 

713 
539 

849 

Together     . . 

4675 

318 

68 

100  0 

*  Chiefly  compiled  from  analyses  by  Stahl-Schroder,  Maly's  JaJires-Bericht 
Thier-Chemie,  1897,  xxvii.  699.  See  also  Lafayette  B.  Mendel,  AmirUan  Journal 
of  Physiology,  1898,  i.  225. 

'  Archiv.  f.  Hygiene,  1885,  iii.  443. 

■  Probably  mostly  in  form  of  amides. 


266 


FOOD  AND  DIETETICS 


It  will  be  observed  that  as  a  class  they  contain  but  little 
dry  substance.  Of  this,  a  comparatively  large  amount  is  nitro- 
genous matter,  the  remainder  being  chiefly  made  up  of  carbo- 
hydrates. The  older  fungi  contain  more  nitrogen  than  the  younger 
plants,  and  those  which  are  cultivated  are  richer  than  those  which 
grow  wild.  It  must  not,  however,  be  supposed  that  the  nitrogenous 
matter  of  the  fungi  is  all  in  a  form  available  for  nutrition.  On  the 
contrary,  a  large  proportion  of  it  is  in  the  form  of  amides  and  other 
non-protein  bodies.  Indeed,  a  reference  to  the  table  will  show  that 
the  actual  amount  of  albuminoid  matter  which  the  fungi  contain  is, 
with  the  exception,  perhaps,  of  truffles,  by  no  means  large  at  all. 

It  is  probably  to  the  amides  and  their  allies  that  most  of  the 
peculiar  flavour  of  the  fungi  is  to  be  attributed. 

Recent  analyses^  of  the  different  forms  of  nitrogen  present  in  some 
common  fungi  have  yielded  the  following  results  : 


Total  N 

Protein  N 
'  Extractive  '  N  . . 
Indigestible  protein  N 
Digestible  ,; 


Cantha- 

Boletus 

Laciarius 

MoicheUa. 

Cibarius. 

Eduiis. 

Deliciosus. 

EscuUnta. 

269 

387 

3" 

4  99 

229 

273 

251 

418 

040 

114 

0  60 

o-8i 

1-46 

065 

105 

I  90 

0*79 

210 

1-41 

219 

Agaricus 
Caiu/estrii. 


738 
489 
249 
117 
364 


Starch  is  not  represented  amongst  the  carbohydrates  of  the  fungi. 
They  contain  instead  a  curious  and  rare  sugar  called  trehalose 
(tnycose)"  and  a  substance  termed  mannite,  v.hich  is  the  parent  of 
a  sugar  named  mannose.  The  nutritive  value  of  both  of  these  sub- 
stances is  unknown.  There  is  some  reason  to  believe  that  mannite, 
at  least,  is  not  easily  assimilated.^  The  fungi  contain  also  a  good 
deal  of  cellulose,  which  seems  to  differ  somewhat  from  that  found  in 
most  plants. 

As  a  result  of  cooking  fungi  shrivel  up  considerably.  This  is  due 
to  coagulation  of  the  contents  of  the  cells,  which  shrink  instead  of 
bursting,  as  they  probably  would  do  if  they  contained  starch.  They 
lose,  also,  much  of  their  rcn  orotein  nitrogenous  constituents,  and 
with  these  much  of  their  flavour.  They  also  gain  in  water  to  some 
extent,  so  that  a  stewed  mushroom  contains  only  about  2  per 
cent,  of  soUd  matter.* 


*  Mendel,  Amer.  Journ.  of  Physiolo?.,  1898,  i.  225. 

*  Winterstein,  Zett.  f.  Physiolt  i;.  Chetn.,  1899,  xxvi.  438. 
'  Jaffe,  Zeit.f.  Physiolog.  Chcm.,  1883,  vii.  297. 

*  See  analysis  by  Katherine  J.  Williams,  Journ.  of  Chem.  Soc,  1892,    xi.  226. 


NUTRITIVE  VALUE  OF  FUNGI  267 

Fungi  are  not  easily  digested  in  the  stomach.  This  is  matter  of 
common  knowledge.  The  difficulty  is  probably  largely  due  to  the 
amount  of  cellulose  which  they  contain,  and  to  the  shrinkage  and 
greater  compactness  which  result  from  cooking.  The  pain  and  dis- 
comfort which  they  are  apt  to  produce  in  the  stomach  have  often 
been  wrongly  attributed  to  poisons,  and  in  consequence  fungi  which 
are  merely  indigestible  have  been  regarded  as  inedible.  Recent 
experiments  in  vitro  have  amply  confirmed  their  indigestibility,^ 

The  absorption  of  the  fungi  is  also  very  imperfect.  One  observer* 
took  large  quantities  of  fresh  mushrooms  daily.  He  found  that 
1 9  per  cent,  of  the  dry  substance  and  33*7  per  cent,  of  the  protein 
escaped  absorption.  Another  got  even  less  favourable  results,^  two- 
fifths  of  the  protein  being  excreted  unchanged.  Artificial  digestion 
outside  the  body  has  yielded  similar  results.*  On  the  other  hand, 
as  one  would  expect,  the  absorption  is  considerably  better  if  the 
mushrooms  are  taken  in  the  form  of  powder,  but  even  in  that  case 
29  per  cent,  of  the  protein  was  lost.* 

On  the  whole,  mushrooms  and  other  fungi  must  be  ranked  with 
such  substances  as  green  vegetables,  carrots  and  black-bread  as 
amongst  the  wasteful  foods. 

The  nutritive  value  of  the  fungi  has  been  very  much  exaggerated. 
Thus,  they  have  been  described  as  vegetable  beefsteaks  ;  it  has  been 
pointed  out  that  the  Patagonians  and  natives  of  Terra  del  Fuego  live 
largely  upon  them,  and  their  more  extensive  use  has  been  urged 
upon  the  poorer  classes  in  this  country.  This  is  partly  owing  to  the 
failure  to  recognise  that  about  one-third  of  their  nitrogenous  matter 
is  in  a  form  which  is  useless  for  the  purposes  of  nutrition,  and  partly 
to  ignorance  of  the  very  imperfect  degree  to  which  such  foods  are 
capable  of  being  absorbed.  Further,  the  carbohydrates  which  the 
fungi  contain  must  be  regarded  as  of  very  uncertain  nutritive  value. 
The  fungi  cannot,  therefore,  be  looked  upon  as  foods  of  any  greater 
value  and  importance  than  fresh  vegetables,  and  when  one  considers 
the  high  price  paid  for  many  of  them,  such  as  truffles,  they  must  be 
regarded  as  pure  luxuries.  This  conclusion  was  arrived  at  as  early 
as  1824  by  Dr.  Kitchiner,  who  stated  in  his  '  Cook's  Oracle' that 
he  did  not  believe  that  mushrooms  were  really  nutritious.  Pereira 
expressed  a  similar  opinion  twenty  years  later.     It  only  remains  to 

1  Gane,  Food  and  Sanitation,  April  22,  1899. 

2  Saltet,  Archiv.f.  Hygiene,  1885.  iii.  443- 

»  Uffelmann,  Archiv.  f.  Hygiene,  1887.  vi.  105. 

*  Morner,  Zeit.f.  Physiolog.  Chem.,  1886,  x.  503. 

•  Uffelmanu,  Archiv.f.  Hygiene,  1887,  vi.  105. 


268  FOOD  AND  DIETETICS 

add  that  when  eaten  in  large  amount  they  rapidly  produce  a  feeling 
of  satiety,  and  this  must  always  constitute  a  further  obstacle  to  their 
taking  serious  rank  as  articles  of  diet. 

Alga. 

This  group  includes  the  seaweeds,  several  varieties  of  which,  e.g., 

laver,  dulse,  etc.,  are  occasionally  used  as  foods.     The  only  one 

which  demands  special  consideration  is  Irish  or  Carraigeen  moss 

{Chondrus  crispus),  which  is  not  only  sometimes  used  as  an  ordinary 

article  of  diet,  but  finds  a  place  also  among  the  dietetic  resources  of 

the  sick-room.     Irish  moss  comes  into  the  market  in  a  dried  form, 

and  has  approximately  the  following  composition  (Church) : 

Water  i8  8  per  cent. 

Nitrogenous  matter  ••         ,.         ..  9-41       „ 

Mucilage,  etc.  ..         .,         ..         ..  554        „ 

Cellulose        ..  .,         .,         ..         ,.  22         „ 

Mineral  matter        ,.         ..         ..         ..  142        „ 

Its  chief  constituent  is  the  substance  described  in  the  analysis  as 
'  mucilage,'  but  which  is  also  known  as  lichenin.  This  substance 
is  insoluble  in  cold  water,  but  swells  up  and  dissolves  when  boiled, 
and  if  present  in  sufficient  amount  sets  to  a  yellowish  jelly  on 
cooling.  Its  chemical  nature  is  obscure.  When  boiled  with  acids 
it  yields  a  small  quantity  of  sugar,  but  of  what  nature  is  not 
definitely  determined.*  Of  this,  however,  there  is  no  doubt,  that  the 
mucilaginous  substance  in  Irish  moss  is  quite  unaffected  by  the 
ordinary  starch-digesting  fluids  (saliva  and  pancreatic  juice)  met 
with  in  the  body.  For  this  reason  its  nutritive  value  must  remain 
open  to  grave  question,  and  at  present  one  is  only  justified  in 
regarding  it  as  a  substance  capable  of  yielding  a  bland  and  soothing 
drink  which  may  be  of  value  in  irritable  conditions  of  the  throat. 
It  is  sometimes  recommended  as  a  substitute  for  starch  in  cases  of 
diabetes ;  but  although  it  may  not  aggravate  that  disease,  it  is  very 
doubtful  whether  it  contributes  in  any  important  degree  to  the 
nourishment  of  the  patient.  That  this  is  extremely  unlikely  is 
rendered  still  more  evident  by  the  fact  that  Irish  moss  jelly  contains 
only  3  per  cent,  of  solid  matter,  the  remainder  being  water.  A 
teacupful  of  such  jelly  would  furnish  only  \  ounce  of  solid  matter, 
or  as  much  as  the  weight  of  a  shilling.     Whether  the  nitrogenous 

1  In  a  specimen  of  Irish  moss  which  I  examined,  I  found  only  6'3  per  cent,  of 
nitrogenous  matter  and  i6"6  per  cent,  of  ash. 

2  The  sugar  does  not  appear  to  be  glucose.  I  have  not  found  that  it  ferments 
with  yeast.  It  gives  an  imperfect  pentose  reaction  with  phloroglucin.  The 
lichenin  of  Ireland  moss  gives  on  hydrolysis  a  large  yield  of  a  reducing  sugar, 
which  ferments  with  yeast,  and  gives  no  phloroglucin  reaction  (see  also  p.  269). ' 


LICHENS  269 

matter  of  Irish  moss  contributes  to  the  nourishment  of  the  body 
must  also  be  left  undetermined.  It  is  not  likely  that  it  is  all  present 
in  a  protein  form.  The  mineral  constituents  are  very  abundant, 
and  contain  traces  of  iodine,  but  not  sufficient  to  exert  any  effects  on 
nutrition. 

Lichens. 
The  only  lichen  which  we  need  consider  is  the  so-called  Iceland 
moss  {Cetraria  islandica).     In  its  commercial  form  it  resembles  Irish 
moss,  but  is  much  darker  in  colour.    According  to  Church's  analysis, 
its  composition  is  as  follows : 

Water  ..         ..         ••         ..         ..  100  per  cent. 

Proteia  87 

Lichen  starch  ,,         700 

acids,  etc. 63 

Cellulose 35 

Mineral  matter        15 

A  more  recent  analysis  of  the  commercial  article  dried  at  105°  C. 
has  been  made  by  Ernest  W.  Brown,*  with  the  following  result : 

Total  nitrogen 056  per  cent. 

Protein  nitrogen  ..         ..         ..         ..         ..  0-32  „ 

Extractive  nitrogen 014  „ 

Ether  extract ••         ••  12  „ 

Cellulose  53  „ 

Ash         22  „ 

Soluble  carbohydrates  (as  dextrose)  ..         ..  433  „ 

Material  soluble  in  85  per  cent,  alcohol     ..         ..  161  „ 

He  describes  two  kinds  of  carbohydrates  as  occurring  in  the 
substance :  (i)  Lichenin,  which  forms  the  jelly  and  yields  dextrose 
on  hydrolysis,  but  is  unaffected  by  digestion  and  probably  does  not 
form  glycogen ;  and  (2)  iso-lichenin,  which  is  present  in  much  smaller 
amount  and  resembles  soluble  starch,  but  on  digestion  yields  only 
dextrins — no  sugar. 

It  is  evident  from  the  chemical  nature  of  the  substance,  from  the 
resistance  of  its  constituents  to  digestion,  and  from  the  small  amount 
of  it  ever  present  in  a  jelly,  that  its  nutritive  value  must  be  regarded 
as  practically  nil. 

*  Amtrican  Journal  0/ Physiology,  1898,  i.  ^^^, 


[  270  ] 


CHAPTER  XV 

SUGAIt,  SPICES,  AND  CONDIMENTS 

Sogar. 

The  importance  of  sugar  as  an  article  of  diet  is  so  great  that  it  may 
be  well  to  devote  a  little  space  to  its  special  consideration. 

Several  different  varieties  of  sugar  enter  into  the  composition  of 
articles  of  diet,  but  for  practical  purposes  they  may  be  divided 
into  two  groups  :  (i)  The  sucroses,  known  chemically  as  the  di- 
saccharids  (C^gHooOji),  the  chief  examples  of  which  are  cane-sugar 
(sucrose),  beet-sugar,  maple-sugar,  malt-sugar  (maltose),  and  milk- 
sugar  (lactose) ;  (2)  the  glucoses,  or  monosaccharids  (CgH^jOj), 
exemplified  by  grape-sugar  (dextrose),  fruit-sugar  (laevulose),  and 
iuvert  sugar,  which  is  a  mixture  of  those  two,  and  is  best  known  in 
the  form  of  honey. 

We  may  now  consider  each  of  these  varieties  in  some  detail. 

I.  Cane-sugar,  or  sucrose,  is  the  most  familiar  of  all  kinds  of 
sugar.  It  is  most  commonly  derived  from  certain  special  grasses, 
such  as  the  sugar-cane  or  sorghum,  but  occurs  also  in  smaller 
amount  in  a  great  many  plants  and  fruits.  When  derived  from 
other  sources  than  the  sugar-cane,  special  names,  such  as  beet-sugar 
or  maple-sugar,  are  usually  given  to  it ;  but  it  must  be  distinctly 
understood  that  these  are  chemically  indistinguishable  from  the  form 
of  sugar  derived  from  the  sugar-cane. 

Cane-sugar  has  been  in  use  in  the  Avorld  as  a  food  for  many  ages, 
but  it  is  only  within  comparatively  recent  times  that  it  has  been 
manufactured  cheaply  enough  to  take  an  important  place  in  ordinary 
diets.  The  following  brief  history  of  its  introduction  into  Europe  is 
taken  from  a  valuable  pamphlet  on  *  Sugar  as  Food,'  issued  by  the 
United  States  Department  of  Agriculture  :^ 

'  Sugar  from  the  sugar-cane  was  probably  known  in  China  2,000 

*  Farmers'  Bulletin,  No.  535,  1913, 


HISTORY  OF  SUGAR  271 

years  before  it  was  used  in  Europe.  When  merchants  began  to 
trade  in  the  Indies  it  was  brought  westward  with  spices  and  per- 
fumes and  other  rare  and  costly  merchandise,  and  it  was  used  for  a 
long  time  exclusively  in  the  preparation  of  medicines.  An  old 
saying  to  express  the  loss  of  something  very  essential  was,  "  Like  an 
apothecary  without  sugar."  Greek  physicians  several  centuries 
before  the  Christian  era  speak  of  sugar  under  the  name  of  "  Indian 
salt."  It  was  called  "  honey  made  from  reeds,"  and  said  to  be  "  like 
gum,  white  and  brittle  '  But  not  until  the  Middle  Ages  did  Euro- 
peans have  any  clear  idea  of  its  origin.  It  was  confounded  with 
manna,  or  was  thought  to  exude  from  the  stem  of  a  plant,  where  it 
dried  into  a  kind  of  gum.  When  in  the  fourteenth  or  fifteenth 
century  the  sugar-cane  from  India  was  cultivated  in  Northern  Africa, 
the  use  of  sugar  greatly  increased,  and  as  its  culture  was  extended 
to  the  newly-discovered  Canary  Islands,  and  later  to  the  West  Indies 
and  Brazil,  it  became  a  common  article  of  food  among  the  well-to-do. 
In  1598  Hentzer,  a  German  traveller,  thus  describes  Queen  Eliza- 
beth, then  sixty-five  years  of  age :  "  Her  nose  is  a  little  hooked,  her 
lips  narrow,  and  her  teeth  black,  a  defect  the  English  seem  subject 
to  from  their  great  use  of  sugar."  By  many  the  new  food  was  still 
regarded  with  suspicion.  It  was  said  to  be  very  heating,  to  be  bad 
for  the  lungs,  and  even  to  cause  apoplexy.  Honey  was  thought  to 
be  more  wholesome,  because  more  natural  than  the  "  products  of 
forced  invention."  ' 

One  of  the  earliest  records  of  the  use  of  sugar  in  this  country  ^  is 
to  be  found  in  the  accounts  of  the  Chamberlain  of  Scotland  in  the 
year  1319.  Its  price  at  that  time  was  is.  9|d.  per  pound.  Since  then 
the  consumption  of  sugar  has  increased  so  enormously  that  each  of  us 
in  this  country  now  uses  between  80  and  90  pounds  of  it  annually.^ 

The  composition  of  the  sugar-cane  and  its  juice  is  about  as  follows  :3 

Entire  Cane.     Juice. 

Water 7104  794 

„  /19  6  (crystallizable). 

Sugar "02  \  03  (uncrystallizable). 

Cellulose        9'56 

Albuminous  matter  . .         ..        0-55  037 
Fatty  and  colouring  matter          035 

I  o  23 


Soluble  salts 012 

Insoluble  salts          ..         ..        016 
Silica 0-20 


i  See  Bannister's  Cantor  Lectures.  1390. 

*  Calculated  from  the  total  sugar  consumption  of  the  United  Kingdom.  Some 
of  this,  however,  is  re-exported  in  a  manufactured  form  as  biscuits,  jam,  sweets, 
etc. ,  so  that  it  is  probably  nearer  the  mark  to  say  that  the  average  amount  ot 
sugar  consumed  daily  by  each  individual  in  this  country  is  3  ounces. 

»  Thorpe's  '  Dictionary  of  Chemistry,'  1893,  iii.  615. 


272  •       FOOD  AND  DIETETICS 

In  order  to  separate  the  sugar,  the  canes  are  crushed,  and  the 
expressed  juice  is  then  bleached  by  means  of  sulphurous  acid, 
neutralized  with  lime,  and  all  albuminous  matters  coagulated  by 
boiling.  It  is  then  filtered,  evaporated  down,  and  the  uncrystal- 
lizable  sugar  (glucose)  separated  by  aid  of  a  centrifuge.  In  this 
way  the  raw  sugar  is  obtained  in  a  crystalline  form  still  mixed  with 
impurities,  while  the  residue  is  sold  as  molasses  or  treacle,  or  is  used 
to  make  rum.  The  chief  examples  of  raw  cane-sugar  are  '  Barbadoes,* 
'  Clayed,'  and  *  Demerara,'  the  diflferences  in  these  depending  on  the 
mode  of  manufacture.  '  Barbadoes '  is  a  very  dark  sugar,  while 
*  Demerara '  is  characterized  by  a  golden  colour  and  well-defined 
crystal ;  it  has  also  a  fine  flavour,  due  to  its  being  prepared  by  the 
careful  treatment  of  specially  selected  canes. 

Raw  sugar  is  purified  by  the  process  of  refining,  which  consists  in 
remelting  the  sugar,  filtering  it,  and  clarifying  it  by  means  of  char- 
coal. It  is  then  carefully  evaporated  in  vacuo.  If  loaf-sugar  is 
wanted  it  is  run  into  moulds.  Moulded  cube-sugar  is  made  in  the 
form  of  sticks,  and  afterwards  cut  into  cubes  by  machinery.  Granu- 
lated sugars  are  made  in  the  centrifuge.  Other  varieties  depend  on 
the  mode  of  crystallization  and  grinding  to  which  the  sugar  is  sub- 
jected. 

2.  Beet-sugar. — Fully  two-thirds  of  the  '  cane  '-sugar  commonly 
used  is  really  derived  from  the  sugar  beet.  The  following  account 
of  the  growth  of  the  industry  is  derived  from  the  pamphlet  already 
mentioned  : 

*  Marggraf,  a  chemist,  of  Berlin,  first  discovered  in  1747  that 
beets,  with  other  fleshy  roots,  contained  crystallizable  sugar  identical 
with  that  of  the  sugar-cane.  In  1796  Marggraf's  pupil,  Achard, 
erected  the  first  manufactory  for  beet-sugar,  and  in  1799  he  brought 
the  subject  before  the  French  Academy.  He  manufactured  beet- 
sugar  on  his  farm  in  Silesia,  and  presented  loaves  of  refined  beet- 
sugar  to  Frederick  William  III.  of  Prussia  in  1797  ;  but  the  2  to  3 
per  cent,  of  sugar  that  could  be  extracted  by  the  methods  then  in 
use  was  too  small  for  commercial  success.  A  new  stimulus  was 
given  by  the  sugar  bounties  of  Napoleon  in  1806,  and  methods  were 
rapidly  improved,  especially  in  France.  Two  great  difficulties  were 
still  to  be  met :  the  percentage  of  sugar  present  in  the  beet  was 
small  (6  per  cent.),  and  it  was  separated  with  great  difficulty  from 
the  many  non-sugar  constituents,  some  of  them  acrid  and  of  very 
unpleasant  taste.  Science  now  came  to  the  rescue,  and  a  beet  was 
gradually  developed  having  a  larger  percentage  of  sugar  and  a 
smaller  percentage  of  the  imdesirable  impurities.     Barber  says  that 


CANE-SUGARS  373 

in  1836  18  tons  of  beetroot  were  necessary  to  produce  i  ton  of  sugar ; 
in  1850  this  quantity  was  reduced  to  I3'8,  in  i860  to  127,  tons;  and 
in  1889  to  9-25  tons.  From  6  per  cent,  of  sugar,  as  found  by  Marggraf, 
the  sugar  beet  of  good  quality  now  contains  15  per  cent,  and  more, 
12  per  cent,  being  considered  necessary  for  profitable  manufacture.' 

The  sugar  is  extracted  from  the  beets  by  rasping  them  to  a  pulp, 
extracting  and  evaporating  in  vacuo,  with  subsequent  decoloration 
by  means  of  animal  charcoal. 

To  the  ordinary  consumer  beet-sugar  is  hardly  distinguishable  from 
that  derived  from  the  sugar-cane,  and  it  has  already  been  stated  that 
to  the  chemist  the  two  are  really  identical.^  There  is  no  evidence 
for  the  statement  sometimes  made,  that  beet-sugar  is  more  injurious 
to  health  than  genuine  cane-sugar ;  but  I  am  informed  by  manu- 
facturers that  for  some  purposes  sugar  derived  from  the  cane  is 
preferable,  e.g.,  in  the  manufacture  of  fruit  syrups  and  British  wines. 
It  is  said  to  be  less  liable  to  fermentation.' 

3.  Maple-sugar  is  derived  from  the  sugar  maple  of  North  America 
by  tapping  the  bark  in  early  spring  and  allowing  the  sap  to  escape 
as  it  flows  upward.  The  sap  is  evaporated  and  the  sugar  allowed 
to  crystallize  out  while  the  residue  is  used  as  maple  syrup.  One 
maple-tree  yields  about  4  pounds  of  sugar  in  a  season. 

There  is  no  chemical  difference  between  maple-sugar  and  that 
derived  from  the  cane  or  beet,  but  it  contains  certain  ethereal  sub- 
stances and  organic  acids  which  give  it  its  peculiar  flavour.  It  is 
probably  on  the  presence  of  these  that  the  slightly  laxative  qualities 
of  maple-sugar  depend.  As  a  commercial  source  of  sugar  the  maple 
cannot  compare  with  either  the  cane  or  the  beet,  and  maple-sugar  is 
now  chiefly  used  as  a  luxury  and  for  the  sake  of  its  agreeable  taste. 

The  average  composition  of  these  sugars  in  their  raw  state  is  as 
follows : ' 

Sour..  Wat..         Cane-su^ar.     ^1^^^;,^^^      ^*^- 

Sugar-cane..         .•        216  9333  424  1-27 

Sugar  beet  ..         ..         290  9200  259  256 

Maple  . .         . .  —  8280 

After  being  subjected  tc  the  process  of  refining,  sugar  is  practically 
a  pure  chemical  substance.  It  is  indeed  '  the  purest  food- substance 
in  commerce  '  (Wynter  Blyth). 

*  It  has  been  aptly  remarked  by  a  writer  in  the  British  Medical  Journal  (1901, 
i.  1119),  that  the  difference  between  cane-sugar  and  beet-sugar  is  'not  achemical 
but  a  physiological  one — a  question  of  taste  and  flavour.  It  is  a  difference 
similar  to  that  between  vin  ordinaire  and  Chateau  Margaux,  and  between  silent 
spirit  faintly  coloured  and  genuine  Scotch  whisky.' 

'  This  is  only  true  if  the  beet-sugar  has  been  imperfectly  purified. 

'  'Sugar  as  Food,'  p.  12. 

18 


274  FOOD  AND  DIETETICS 

4.  The  remaining  sugars  of  this  group  are  malt-sugar,  or  maltose, 
and  milk-sugar,  or  lactose.  Both  of  these,  though  disaccharids, 
differ  very  considerably  in  chemical  and  physical  properties  from  the 
sugars  we  have  been  considering.  Milk-sugar  has  already  been 
described  (p.  no),  and  we  may  defer  the  study  of.  maltose  until  we 
come  to  malt-extracts  (p.  566). 

Certain  substances  derived  from  cane-sugar  deserve  brief  men- 
tion. When  strongly  heated,  sugar  melts  into  a  yellowish  liquid, 
and  undergoes  some  physical  alteration,  so  that  on  cooling  it  does 
not  crystallize,  but  forms  a  transparent,  brittle  mass,  familiar  to 
everyone  as  barley  sugar.  If  heated  to  a  still  higher  temperature 
its  colour  darkens,  and  it  acquires  a  bitter  taste,  the  product  being 
caramel,  which  is  so  largely  used  in  cooking  operations. 

Treacle,  molasses,  and  golden  syrup  are  produced  as  by-products 

in  the  manufacture  of  crystallized  sugar.     Their  syrupy  consistence 

is  in  part  due  to  the  fact  that  the  impurities  which  they  contain 

prevent  the  cane-sugar  from  crystallizing,  and  partly  also  to  their 

being   fairly   rich   in    uncrystallizable  fruit-sugar.      The  following 

represents  their  composition ; 

IVest  Indian  ^       ,  Golden 

Molasses.  ■"'"'"'•  Syrup. 

Cane-sugar..         ..         ..        ,.        470  325  390 

Fruit-sugar 204  372  330 

Extractive  and  colouring  matter..           27  35  28 

Salts             ..         ..         ..         ..           26  34  25 

Water          273  234  227 

It  is  interesting  to  compare  the  proportion  of  nutritive  matter  in 
these  with  that  in  malt-extract  (p.  566),  but  to  this  subject  we  shall 
return  later. 

5.  The  other  great  group  of  sugars  is  the  glucoses,  or  mono- 
saccharids.  The  best  example  of  these  is  dextrose,  which  occurs  so 
abundantly  in  the  grape.  When  grapes  are  dried  to  form  raisins,  the 
dextrose  separates  out,  and  may  be  recognised  in  the  raisins  in  the 
form  of  little  yellowish-white  granular  masses.  Commercial  glucose 
is  usually  got  by  boiling  starch  with  acids.  It  occurs  in  a  syrupy 
form.  When  heated  it  turns  brown,  and  is  used  in  cookery  as 
'  sugar  colouring.'  Mixed  with  egg-albumin,  it  is  largely  employed 
in  the  preparation  of  *  icing '  and  '  fondants '  in  confectionery  and  in 
the  manufacture  of  bonbons. 

Fruit-sugar,  or  laevulose,  is  found,  as  its  name  implies,  in  most 
fruits.  It  is  characterized  by  being  almost  uncrystallizable.  It  is 
hardly  ever  met  with  in  an  isolated  form  in  dietetics,  but  is  some- 
times administered  to  diabetic  patients,  by  some  of  whom  it  is 
better  borne  than  any  other  form  of  sugar  (p.  498). 


CANE-SUGARS  275 

Invert  sugar  is  a  mixture  of  dextrose  and  lasvulose.  It  can  be 
prepared  from  cane-sugar  by  the  action  of  ferments  or  by  simple 
boiling,  but  more  readily  by  boiling  with  acids.  This  '  inversion ' 
of  cane-sugar,  as  it  is  called,  goes  on  pretty  rapidly  when  cane- 
sugar  is  boiled  with  fruit-juice,  the  active  agent  being  the  vegetable 
acid  of  the  fruit.  Thus,  a  large  proportion  of  the  cane-sugar 
used  in  making  jam  is  converted  into  invert  sugar  in  the  process. 
It  is  important  to  remember  also  that  invert  sugar  does  not 
crystallize. 

Honey  is  the  most  familiar  form  of  invert  sugar.  It  contains 
about  equal  parts  of  dextrose  and  Isevulose,  its  flavour  being 
due  to  the  presence  of  small  amounts  of  volatile  substances 
derived  from  the  flowers.  The  mean  composition  of  pure  honey 
was  found  by  Dr.  Sieber  to  be  as  follows; 

HONEY. 

Moisture 19-98  per  cent. 

Grape-sugar  (dextrose) 34'7i        » 

Laevulose  ..         ..         ..         ..         ..  39*24        „ 

Substances  other  than  sugar    ..         ••  5*02        „ 


The  comb  consists  of  fatty  substances,  which  are  probably 
incapable  of  digestion. 

The  basis  of  sweetmeats  is  either  cane-sugar  or  one  of  the 
glucoses.  Sugar-candy  is  one  of  the  purest.  It  consists  of  cane- 
sugar  which  has  been  allowed  to  crystallize  round  threads.  It 
contains  about  20  per  cent,  of  water  and  80  per  cent,  of  crystal- 
lizable  sugar. 

Toffee  consists  of  melted  sugar  and  butter  in  almost  equal  propor- 
tions. Everton  toffee  has  about  34  per  cent,  of  cane  and  27  per 
cent,  of  invert  sugar,  which  has  been  derived  from  cane-sugar 
by  the  prolonged  boiling.  It  is  a  highly  nutritious  substance,  and 
makes  an  agreeable  substitute  for  •  cod-liver-oil  and  malt  *  in  the  case 
of  ill-nourished  children. 

Chocolate  contains  about  45  per  cent,  of  cane-sugar,  but  no 
dextrose  or  laevulose.  The  rest  of  it  is  composed  of  cocoa-powder. 
(For  analyses,  see  p.  328.) 

Invert  sugar,  or  a  mixture  of  glucose  and  albumin,  is  largely 
used  in  the  preparation  of  uncrystallized  sweets,  such  as  the  creamy 
matter  in  the  interior  of  chocolate  drops. 


276  FOOD  AND  DIETETICS 

The  colouring  of  sweets  is  derived  either  from  burnt  sugar  or 
from  one  of  the  anilin  dyes,  most  commonly  eosin.  Cochineal  is 
also  a  favourite  colourer.  It  is  interesting  to  note  that  aniline  dyes 
may  be  excreted  in  the  urine  almost  unchanged,  and  cases  are  on 
record  where  patients  have  been  supposed  to  be  passing  blood, 
when  they  had  merely  been  sucking  red  sweets.  There  is  no  reason 
to  suppose,  however,  that  such  substances  are  in  any  way  harmful 
to  life. 

Jams  consist  essentially  of  fruit  preserved  in  a  strong  solution  of 
sugar.  We  have  already  seen  that  the  acids  of  the  fruit,  aided  by 
the  high  temperature  employed  in  the  course  of  preparation,  bring 
about  the  conversion  of  a  considerable  proportion  of  the  cane-sugar 
into  the  invert  form.  Home-made  jam  is  boiled  for  a  longer  time 
than  the  commercial  article,  and  consequently  contains  more  invert 
and  less  cane-sugar  than  the  latter.  Aitchison  Robertson^  gives  the 
proportion  of  cane-sugar  in  most  home-made  jams  as  20  per  cent., 
while  commercial  jams  have  anything  from  10  to  50  per  cent.  In 
some  home-made  jams  which  he  examined  the  proportion  of  cane- 
sugar  which  had  been  inverted  was  as  follows  : 

Proportion  oj  Cane-sugar 
inverted. 

Strawberry  two-fifths 

Raspberry  ..         ..         ..         three-fifths 

Blackberry  ..         ..         ..         four-fifths 

Marmalade  ..         ..         ..         five-sixths 

Plum  ..         ..         ..         ..         six-sevenths 

The  importance  of  these  figures  is  derived  from  the  fact  that  the 
larger  the  proportion  of  cane-sugar  which  has  been  inverted,  the  less 
likely  is  the  jam  to  interfere  with  digestion  (see  p.  278). 

Commercial  glucose,  on  account  of  its  incapability  of  crystallizing, 
is  often  used  to  make  jam  from  inferior  fruit  or  from  the  remains  of 
fruit,  the  juice  of  which  has  been  used  to  make  fruit  syrups  and 
jellies.  Such  jam  may  have  a  good  appearance,  but  is  deficient  in 
fruit  flavour.     It  is,  however,  quite  wholesome  and  nutritious. 

The  gelatinizing  power  of  jellies  is  due  to  the  presence  of  pectin 
in  the  fruit  (p.  255).  If  boiled  too  long,  the  power  of  gelatinizing  is 
lost,  and  a  syrup  results  instead  of  a  jelly.  In  commercial  jellies 
gelatin  is  sometimes  added  to  prevent  this. 

Almost  half  the  weight  of  any  given  quantity  of  jam  is  made  up 
of  sugar  in  some  form  or  another.  The  nutritive  value  of  jam  has 
already  been  considered  (p.  137). 

^  '  The  Value  of  Saccharine  Foods  as  Articles  of  Diet,'  Scottish  Medical  and 
Surgical  Journal,  1898,  iii.  30. 


DIGESTIBILITY  OF  SUGARS  *V 


Digestion  of  Sugar. 

The  first  factor  which  determines  the  digestibility  of  a  sugar  is  its 
chemical  form.     No  matter  in  what  form  sugar  is  consumed  in  the 
food,  it  can  only  be  assimilated  as  a  monosaccharid  (dextrose  or 
laevulose).     Hence,  we  find  that  provision  is  made  in  the  alimentary 
canal  for  the  conversion,  by  means  of  suitable  ferments,  of  all  forms 
of  sucrose  (disaccharids)  into  dextrose  and  laevulose ;  i.e.,  they  are 
inverted.     It  is  evident,  then,  that  from  a  dietetic  point  of  view  we 
may  speak  of  the  sucroses  as  undigested  and  the  glucoses  as  pre- 
digested  sugars.     It  now  becomes  clear  why  sweet  fruits  are  such 
important  dietetic  sources  of  sugar.     It  is  because  they  contain  the 
latter  in  a  form  in  which  it  is  fit  for  direct  absorption  into  the  blood. 
For   the   same  reason  honey  must   be  regarded  as  a  very  easily 
digested  saccharine  substance,  and  the  importance  of  the  inversion 
which  cane-sugar  undergoes  in  the  manufacture  of  jams  also  be- 
comes manifest.     The  superiority  of  home-made  over  commercial 
jams  is  also  set  in  a  clearer  light  by  reference  to  these  considerations. 
The  second  factor  which  influences  the  digestibility  of  a  sugar  is 
the  degree  of  concentration  of  its  solution.     In  strong  solution  sugar  is  an 
irritant  to  the  tissues.     In  contact  with  the  skin,  it  is  apt  to  set  up 
superficial  inflammation.     This  is  familiar  in  the  form  of  the  eczema 
which  is  apt  to  appear  in  diabetics  from  the  contact  of  the  sugar- 
containing   urine   with   the   skin,  and   from   the   similar   condition 
occurring  on   the  arms   of  grocers   and   other   persons  who   have 
frequently  to  handle  sugar,  and  it  is  on  account  of  its  irritating 
properties  that  sugar  cannot  be  used  as  a  subcutaneous  aliment, 
though  otherwise  well  adapted  to  fulfil  that  function.     All  attempts 
to  use  it  in  that  fashion  have  been  frustrated  by  the  pain  which  it 
sets  up  (see  p.  577).     The  same  is  true  of  the  stomach.     Brandl, 
experimenting  on  dogs,  found  that  a  5*7  per  cent,  solution  of  sugar 
produced  reddening  of  the  mucous  membrane ;  if  the  concentration 
was  increased  to  10  per  cent.,  the  mucous  membrane  became  dark 
red,  while  a  20  per  cent,  solution  produced  pain  and  great  distress. 
This  irritating  effect  on  the  mucous  membrane  is  accompanied  by 
the   production   of  much  mucus  and  the  pouring  out  of  a  highly 
acid  gastric  juice.     These  irritating  effects  seem  to  be  much  more 
pronounced  in  the  case  of  cane-sugar  than  in  that  of  the  glucoses. 
Aitchison  Robertson^  injected  250  cc.  of  a  20  per  cent,  solution  of 

*  'Digestion  of  Sugars  in  Some  Diseased  Conditions  of  the  Body,'  Edinburgh 
Utdical  Journal,  1S94,  xl.,  pt.  i.  496. 


278  FOOD  AND  DIETETICS 

cane-sugar  into  the  stomach  of  a  patient  who  was  suffering  from 
chronic  gastric  catarrh.  Shortly  afterwards  the  patient  felt  sick, 
and  vomited  a  very  acid  fluid  which  put  his  teeth  on  edge.  He 
complained  also  of  heart-burn  and  flatulence,  and  of  severe  pain 
in  the  region  of  the  stomach.  A  solution  of  invert  sugar  of  the 
same  strength  produced  no  discomfort.  The  experiment  was  repeated 
with  similar  results  in  other  cases  of  dyspepsia.  The  invert  sugfar 
produced  no  unpleasant  symptom,  and  disappeared  rapidly  from  the 
stomach,  while  the  cane-sugar  caused  much  distress,  and  remained 
for  a  long  time. 

The  greater  digestibility  of  invert  sugar  is  here  brought  out  again 
in  great  clearness.  Cane-sugar  may  easily  interfere  with  the  diges- 
tion of  other  foods,  by  reason  of  the  great  outpouring  of  mucus  in 
the  stomach  which  its  presence  induces.  Schiile^  found  that 
lo  to  30  grammes  (2  to  6  lumps)  of  cane-sugar,  when  taken  with  an 
ordinary  test  breakfast,  produced  no  appreciable  efi^ect  on  its  diges- 
tion; but  when  the  quantity  was  increased  to  120  grammes  consider- 
able delay  of  digestion  ensued.  Seeing,  he  says,  that  one  can  easily 
take  80  to  100  grammes  of  sugar  at  dessert  in  the  form  of  ices  and 
sweets,  a  retarding  action  on  the  digestion  of  a  meal  must  not 
unfrequently  be  manifested.  Experiments  by  Ogata  on  dogs  confirm 
these  results.* 

It  is  evident  from  all  this  that,  if  we  wish  to  avoid  the  risk  of 
interfering  with  digestion  by  the  use  of  sugar,  care  should  be  taken 
that  the  latter  is  not  consumed  in  a  concentrated  form,  but  that 
the  comparative  dilution  in  which  sugar  occurs  in  natural  foods, 
such  as  fruits  and  milk,  is  imitated.  This  is  of  special  importance 
in  the  case  of  dyspeptics,  and  the  superiority  of  glucose  for  such 
patients  over  ordinary  cane-sugar  cannot  be  too  strongly  insisted 
upon. 

Another  matter  affecting  the  behaviour  of  different  sugars  in  the 
stomach  is  their  tendency  to  undergo  fermentation.  Three  varieties 
of  such  fermentation  may  be  distinguished:  (i)  Alcoholic,  resulting 
in  the  production  of  alcohol  and  acetic  acid ;  (2)  butyric,  with  the 
formation  of  butyric  acid ;  (3)  lactic,  the  product  being  lactic  acid. 
Now,  it  is  interesting  to  note  that  different  sugars  vary  in  the  readi- 
ness with  which  they  tend  to  undergo  these  different  forms  of 
fermentation.  Some  interesting  experiments  upon  this  point  have 
been  carried  out  by  Aitchison  Robertson.'     He  arranges  the  sugars 

^  Zeit.  /.  Kltn.  Med.,  1896,  xxix.  49. 
'  '  Sugcir  as  Food,'  p.  22. 

•  '  Rate  of  Fermentation  of  Sugars,'  Edinburgh  Medical  Journal,  1894,  xxxix., 
pt  ii.  803. 


ASSIMILATION  OF  SUGARS  379 

in  the  following  order,  according  to  the  rapidity  with  which  they 

tend  to  undergo  each  variety  of  fermentation  : 

Lactic.  Butyric.  Alcoholic. 

Laevulose  (most  fer-  Lsevulose  (most  fer-  Maltose  (most  fer- 
mentable),                        mentable).  mentabie). 

Lactose.  Maltose.  Invert  sugar. 

Dextrose.  Dextrose.  Cane-sugar. 

Invert  sugar.  Invert  sugar.  Dextrose. 

Cane-sugar.  Cane-sugar.  Lasvulose. 

Maltose.  Lactose.  Lactose. 

The  practical  deductions  which  he  draws  from  his  observations 
are  these : 

1.  In  dyspepsia  the  absorption  of  carbohydrates  is  delayed,  and 
therefore  all  sugars  tend  to  ferment. 

2.  In  dyspepsia  with  lactic  acid  formation,  one  should  avoid 
dextrose,  laevulose  and  invert  sugar,  and  use  cane-sugar,  maltose 
and  lactose  in  moderate  amount. 

3.  In  butyric  fermentation  lactose  should  be  preferred. 

4.  In  alcoholic  and  acetic  fermentation  one  should  forbid  invert 
sugar  and  laevulose,  and  give  lactose. 

It  will  be  observed  that,  of  all  sugars,  lactose  is  least  liable  to 
fermentation.  This  is  another  point  in  favour  of  the  value  of  a 
milk  diet  in  stomach  complaints. 

The  last  point  connected  with  the  influence  of  sugar  on  the 
digestive  organs  is  its  supposed  injurious  effects  on  the  teeth.  The 
impression  that  sugar-eating  is  bad  for  the  teeth  is  so  widespread 
that  one  can  hardly  suppose  it  to  be  devoid  of  all  real  basis.  It 
must  be  admitted,  however,  that  the  supposition  is  not  supported  by 
any  very  conclusive  observations.  If  sugar  does  destroy  the  teeth, 
it  probably  does  so  indirectly  by  lingering  in  the  crevices  of  the 
mouth,  and  leading  to  the  production  of  acids  which  eat  away  the 
enamel. 

Assimilation  of  Sugars. 

The  fate  of  sugar  after  entering  the  blood  is  to  be  converted  by 
the  liver  into  glycogen.  What  becomes  of  it  after  that  is  still 
disputed,  but  everyone  is  agreed  that  glycogen  is  the  form  in  which 
sugar  is  stored  in  the  body,  for  a  time,  at  least.  Now,  it  has  been 
found  by  physiological  experiment  that  it  is  not  all  sugars  which  are 
capable  of  being  converted  into  glycogen.  It  is  only  those  which 
can  be  directly  fermented  by  yeast — fermented,  that  is  to  say,  without 
being  first  changed  into  invert  sugar. ^     Of  the  sugars  commonly 

*  See  Crem'er,  Zeit.  /.  Biologic,  1892,  xxix.  484,  and  1895,  xxxii.  49;  also 
Fritz  Voit,  Deut.  Archiv.  /.  Klin.  Med.,  1897,  Iviii.  523,  and  Achard  and  Weil, 
drfhives  4*  Med.  Exper.,  1898,  x.  816. 


28o  FOOD  AND  DIETETICS 

consumed,  cane-sugar  and  lactose  are  not  directly  fermented  by 
yeast,  and,  in  order  that  they  may  be  stored  up  as  glycogen,  provision 
has  to  be  made  for  their  previous  inversion.  This  is  met,  as  we 
have  seen,  by  the  production  of  certain  inverting  ferments  in  the 
intestine  which  act  on  these  sugars.  If,  however,  these  ferments 
happen,  in  any  particular  case,  to  be  of  feeble  activity  while  the 
absorptive  power  of  the  intestine  is  great,  some  of  the  sugar  may 
reach  the  blood  unchanged,  and,  being  incapable  of  conversion  into 
glycogen,  straightway  appears  in  the  urine.  Even  in  the  case  of  the 
directly  fermentable  sugars,  if  a  large  quantity  is  absorbed  in  the 
course  of  a  short  time,  the  glycogen-forming  power  of  the  liver  may 
be  unable  to  keep  pace  with  the  demands  made  upon  it,  and  some  of 
the  sugar  will  appear  in  the  urine.  There  results  from  this  what 
is  termed  alimentary  glycosuria.  By  giving  large  quantities  of 
different  sugars  on  an  empty  stomach,  and  observing  whether  or  not 
glycosuria  results,  one  has  been  able  to  determine  what  may  be 
called  the  assimilation  limit  of  each — that  is  to  say,  the  maximum 
quantity  which  can  be  consumed  at  one  time  without  the  overflow 
of  any  of  the  sugar  into  the  urine  taking  place.  These  maximum 
amounts  are  about  as  follows  : 

For  lactose    ..  ..  ..  120  grammes. 

For  cane-sugar  ..  ..  150  to  200  grammes. 

For  laevulose  ..  ..  200  grammes. 

For  dextrose  ..  . .  200  to  250  grammes. 

Lactose,  therefore,  is  the  least  assimilable  of  all  sugars,  and  if  taken 
in  excess  is  the  most  likely  to  result  in  the  production  of  glycosuria. 

It  must  further  be  borne  in  mind  that  the  assimilation  limit  is  not 
the  same  for  all  individuals.  Some  people  are  able  to  convert  more 
sugar  into  glycogen  than  others.  It  has  been  stated  that  persons 
with  a  low  assimilation  limit  are  potential  diabetics  ;  that  is  to  say, 
they  are  more  Hable  than  others  to  become  the  victims  of  diabetes 
mellitus. 

There  is  another  chemical  fact  relating  to  the  assimilation  of 
sugars  which  is  of  some  practical  interest,  and  it  is  this  :  Experi- 
ments have  shown  that  the  only  sugars  capable  of  direct  fermenta- 
tion, and  therefore  of  conversion  into  glycogen,  are  those  which 
contain  either  three  carbon  atoms  or  a  multiple  of  that  number. 
Those  which  contain  five,  seven,  or  any  other  number  of  carbon 
atoms  cannot  be  converted  into  glycogen,  and  accordingly,  should 
they  gain  access  to  the  blood,  are  at  once  excreted  in  the  urine. 
Now,  sugars  ^^^th  five  carbon  atoms  (pentoses)  occur  with  con- 
siderable frequency  in  certain  fruits,  and  hence  pentosuria,  as  it  is 


NUTRITIVE  VALUE  OF  SUGAR  281 

termed,  is  a  not  infrequent  result  of  the  free  consumption  of  such 
foods. 

Notwithstanding  all  this,  it  must  be  noted  that,  if  sugar  be  taken 
along  with  other  food,  and  distributed  uniformly  over  the  day,  very 
large  quantities  can  be  consumed  without  the  danger  of  exceeding 
the  assimilation  limit.  Vaughan  Harley  was  able  to  take  a  pound 
of  cane-sugar  daily — with  injurious  results  as  regards  his  digestion, 
it  is  true,  but  without  producing  glycosuria.  As  a  general  rule,  one 
may  assume  that  ^  pound  can  be  taken  daily  without  any  bad 
results  at  all,  but  the  exact  amount  must  of  necessity  depend  to  a 
large  extent  on  the  muscular  activity  of  the  subject. 

Nutritive  Value  and  Economy  of  Sugar.! 

We  have  seen  that  refined  sugar  is  to  be  regarded  as  a  practically 
pure  carbohydrate.  That  being  so,  its  food  value  must  be  high,  for 
every  gramme  of  it  will  yield  4*1  Calories  of  energy.  An  ordinary 
lump  of  loaf-sugar  weighs  5  grammes,  and  yields  therefore  fully 
20  Calories.  Four  such  lumps  contain  as  much  carbohydrate  as 
a  medium-sized  potato.  It  is  evident  from  these  considerations 
that  even  the  amount  of  sugar  ordinarily  added  to  a  cup  of  tea  may 
contribute  in  no  small  degree  to  the  supply  of  energy  required  by 
the  body  daily.  A  pound  of  butter  will  yield  about  twice  as  much 
energy  as  a  similar  weight  of  sugar,  but  at  nearly  four  times  the 
same  cost,  for  sugar  is  one  of  the  cheapest  fuel  foods — perhaps  the 
cheapest — which  we  possess,  a  shilling  spent  on  it  yielding  11,000 
Calories,  or  more,  even,  than  can  be  obtained  in  the  form  of  bread 
for  a  similar  expenditure. 

This  great  cheapness  of  sugar  is  a  development  of  recent  years, 
and  can  hardly  be  without  far-reaching  efTects  on  the  national  health. 
It  tends  to  make  us  consume  more  carbohydrate  and  less  fat,  for  fat 
is  always  a  dear  form  of  food.  Whether  this  is  an  advantage  it 
would  be  difficult  to  say.  It  is  true  that  sugar  can  replace  fat  as  a 
fuel  in  the  proportion  of  2^  parts  of  the  former  to  i  of  the  latter, 
but  it  does  not  follow  on  that  account  that  sugar  can  perform  all  the 
functions  in  the  body  which  are  usually  fulfilled  by  fat,  provided  that 
proportion  be  observed.  We  have  already  learnt  (p.  22)  that  sugar 
is  more  rapidly  burnt  up  in  the  body  than  fat,  and  is  on  that  account 
a  more  efficient  protein-sparer  than  the  latter.     This  rapid  oxidation 

*  For  an  interesting  discussion  on  this  subject  see  a  paper  by  Dr.  H.  Wil- 
loughby  Gardner  ('  The  Dietetic  Value  of  Sugar  ')  in  the  British  Medical  Journal, 
1901,  i.  loio. 


282  FOOD  AND  DIETETICS 

is  favoured  by  the  ease  with  which  sugar  is  absorbed,  and,  interfering 
as  it  does  with  the  complete  destruction  of  proteins,  probably  explains 
the  bad  effects  sometimes  observed  from  the  use  of  sugar  in  gout 
and  gravel  (p.  517).  The  relative  advantages  of  fat  and  sugar  as 
fat-formers  is  another  unsettled  point.  The  highly  fattening  proper- 
ties of  sugar  are  undoubted  ;  it  is  probably  not  only  itself  capable  of 
being  transformed  into  fat,  but  spares  the  body  fat  and  part  of  that 
in  the  diet  from  combustion ;  but  whether  the  fat  so  formed  is  as 
useful  as  that  which  can  be  stored  up  from  the  fat  in  the  diet  is  a 
question  which  physiology  is  not  yet  in  a  position  to  solve.  The 
point  is  one  of  some  practical  importance  in  the  feeding  of  con- 
valescents, and  in  the  selection  of  cod-liver-oil  or  malt  as  a  fattening 
agent. 

Of  this,  however,  there  can  be  little  doubt,  that  the  great  cheap- 
ness of  sugar  must  have  a  favourable  influence  on  the  health  and 
growth  of  children,  for  it  ensures  to  them  an  ample  supply  of  the 
body  fuel  which  they  so  much  need,  and  which  the  dearness  of  fat 
is  apt  to  make  unattainable.  It  has  the  advantage,  too,  of  being  a 
form  of  fuel  which  few  children  are  likely  to  refuse,  and  that  is  far 
from  being  true  of  fat.^ 

It  is  as  a  muscle  food,  however,  that  sugar  is  of  special  importance. 
We  have  already  learnt  (p.  37)  that  the  carbohydrates  are  probably 
the  chief  source  of  muscular  energy,  and  the  sugars,  on  account  of 
the  ease  and  rapidity  of  their  absorption,  are  better  calculated  to 
fulfil  this  function  than  any  other  member  of  the  carbohydrate 
group. 

It  is  interesting  to  note  that  Brillat-Savarin  pointed  out  long  ago 

that  '  the  English   give  sugar  to  their   blood   horses   in   order   to 

sustain  them  in  the  trials  to  which  they  are  subjected.'     To  Swiss 

guides  and  Arctic  explorers,  too,  the  value  of  such  a  saccharine  food 

as  chocolate  has  long  been  familiar.     It  was  not  until  the  year  1893, 

however,  that  Mosso  first  put  the  value  of  sugar  as  a  muscle  food  to 

the  test  of  experiment.     By  means  of  the  ergograph  he  was  able  to 

show  that  sugar  has  a  notable  effect  in  lessening  muscular  fatigue. 

1  On  the  other  hand,  Bunge  has  uttered  a  warning  note  regarding  the  dangers 
incidental  to  the  great  increase  in  the  dietetic  use  of  sugar  in  recent  times 
('  Der  Wachsende  Zuckerconsum  und  seine  Gefahren,'  Zeit.  f.  Biolcg.,  1901,  xli. 
p.  155).  He  points  out  that  sugar,  if  largely  eaten,  must  diminish  the  amount 
of  other  vegetable  foods  in  the  diet,  whence  there  may  result  a  deficit  in  the 
supply  of  calcium,  iron,  fluorine,  and  other  mineral  ingredients  to  the  blood. 
This  may  tend  to  produce  anaemia  and  caries  of  the  teeth.  He  is  of  opinion 
that  it  is  always  dangerous  to  replace  natural  foods  by  pure  isolated  chemical 
products.  I  think  it  is  not  unlikely,  too,  that  the  greater  consumption  of  sugar 
in  recent  years  may  have  something  to  do  wiih  the  iucreasing  commonae»s  of 
diabetes  which  uiauy  i^ll«ve  lu  eiLi;>t. 


SUGAR  AS  A  MUSCLE  FOOD  283 

The  subject  was  then  taken  up  by  Vaughan  Harley,  who  found, 
working  under  Mosso's  direction,  that  if  he  took  17^  ounces  of 
sugar  a  day  his  power  of  doing  work  was  increased  61  to  76 
per  cent.  He  showed  also  that  the  administration  of  sugar  delays 
the  onset  of  fatigue,  and  that  its  effects  are  rapidly  exerted,  the 
maximum  influence  being  reached  in  about  two  hours.  Schumburg^ 
was  able  to  confirm  these  results  as  regards  extraordinary  muscular 
exertion.  Similar  experiments  have  recently  been  performed  by 
Prautner  and  Stowasser,^  who  found  that  when  sugar  was  added 
to  their  diet  their  power  of  doing  work  was  increased,  while  fatigue 
and  nitrogenous  waste  were  lessened.  They  conclude  that  sugar  is 
a  specially  valuable  food  for  persons  who  have  to  perform  a  single 
muscular  effort,  and  especially  if  they  are  obliged  to  do  so  in  a  state 
of  exhaustion. 

The  results  of  these  scientific  experiments,  which  were  carried 
out  with  due  regard  to  all  possible  sources  of  fallacy,  have  led  to 
an  extensive  practical  trial  of  sugar  as  a  food  for  persons  engaged 
in  muscular  labour.  Two  examples  may  be  mentioned.  During 
the  autumn  manoeuvres  of  the  German  army  some  years  ago, 
a  number  of  the  men  were  given  ten  lumps  of  sugar  daily,  in 
addition  to  their  ordinary  rations.  The  trial  extended  over  five 
weeks,  and  it  was  found  that  the  soldiers  who  had  been  supplied 
with  sugar  marched  better  and  suffered  less  from  hunger,  thirst,  and 
fatigue  than  their  fellows  who  were  not  so  supplied.  As  a  result  of 
the  experiments,  the  surgeon  in  charge  recommended  that  the  sugar 
ration  for  soldiers  should  be  raised  to  60  grammes  per  day  (about 
2  ounces). 

The  other  example  illustrating  the  practical  value  of  sugar  as  a 
muscle  food  is  to  be  found  in  the  experience  of  certain  rowing  clubs 
in  Holland.  They  found  sugar  to  be  a  very  valuable  food  in  training. 
The  rowers  who  used  it  always  won,  on  account  of  their  superior 
powers  of  endurance,  and  it  seemed  to  counteract  the  bad  effects  of 
an  exclusively  meat  diet,  so  that  the  men  did  not  become  '  stale.' 

'  One  case,  as  given  in  detail,  is  very  interesting.  Two  schoolboys, 
seventeen  and  nineteen  years  of  age,  with  only  two  hours  a  day  for 
practice,  at  the  end  of  two  months  entered  for  the  rowing  races. 
No  change  had  been  made  in  their  diet  except  that  they  ate  as 
much  sugar  as  they  wished,  sometimes  as  much  as  one-third  of  a 
pound  at  the  time  of  their  daily  exercise.     One  of  them,  however, 

^  Archiv.  f.  Anat.  und  Physiol.,  1809.  Sup.  BJ.,  p.  289. 
-  CcnuMo.  J.  hit:.  MeJ.,   i^'jj.  \x.  iL.j. 


284  FOOD  AND  DIETETICS 

did  not  make  this  addition  to  his  diet  until  the  third  week,  when  he 
began  to  show  all  the  signs  of  overtraining — loss  of  weight,  and  a 
heavy,  dull  feeling,  with  no  desire  for  study.  On  the  third  day  after 
beginning  the  use  of  sugar  these  symptoms  disappeared.  At  the 
time  of  the  race  both  youths  were  in  fine  condition,  and  were 
victorious  over  their  antagonists,  who  did  not  believe  in  the  use  of 
sugar.     No  bad  after-effects  were  observed. '^ 

Additional  evidence  in  favour  of  the  free  use  of  sugar  in  training 
and  during  the  performance  of  hard  muscular  work  has  been  brought 
forward  by  Steinitzer.^  He  has  found  from  personal  experience  in 
Alpine  climbing  that  his  capacity  for  exertion  is  much  greater  when 
he  partakes  largely  of  sugar,  whilst  at  the  same  time  fatigue  is 
lessened.  The  sugar  is  best  taken  in  solution  in  quantities  of  from 
5  to  10  ounces  spread  over  the  day.  It  may  be  dissolved  in  tea, 
wine  and  water,  or  lemonade.  As  much  even  as  20  ounces  may 
safely  be  taken  for  several  days  on  end  during  hard  exercise  without 
the  least  harm. 

It  certainly  seems  as  if  it  would  be  worth  the  while  of  captains  of 
football  teams  to  try  the  effect  of  serving  round  small  cups  of  black 
coffee,  strongly  sweetened  with  sugar,  at  '  half-time,'  instead  of  the 
usual  lemon.  They  would  probably  be  rewarded  by  the  greater 
endurance  of  their  men  in  the  second  half  of  the  match. 

Spices  and  Condiments. 

The  spices,  condiments,  and  flavouring  agents  generally,  are  not, 
as  a  rule,  foods  in  the  strict  sense  of  the  term ;  that  is  to  say,  they 
are  not  capable  of  supplying  the  body  with  building  material  or 
energy.  None  the  less,  however,  they  are  essential  constituents 
of  the  diet.  Their  importance  rests  upon  the  power  which  they 
possess  of  improving  appetite,  and,  by  so  doing,  of  increasing  the 
digestive  power.  To  the  healthy  man  of  vigorous  appetite  their 
presence  is  less  essential.  It  has  been  found  by  experiment  that 
meat  from  which  all  the  flavouring  ingredients  have  been  extracted 
by  prolonged  boiling  is  as  well  digested  by  healthy  men  as  fresh 
meat  itself,^  in  spite  of  the  fact  that  it  was  eaten  with  but  little 
relish. 

To  persons  of  jaded  appetite,  however.,  and  to  invalids  and  con- 
valescents, the  flavouring  agents  of  the  food  are  very  powerful  aids 

'  *  Sugar  as  Food,'  p.  18. 

*  '  Die  Bedeutung  des  Zuckers  als  Kraftstofi,'  etc.  (Berlin,  Paul  Parey,  J902). 

*  Pettenkofer  and  Ziemssen's  'Handbuch,'  Part  I.,  p.  94,  1S82. 


SPICES  AND  CONDIMENTS  285 

to  digestion,  and  no  adjustment  of  the  diet  in  such  cases  can  be 
regarded  as  satisfactory  which  leaves  this  consideration  out  of 
account.  Their  presence  justifies  the  inclusion  in  the  regimen 
of  many  substances  which  are  otherwise  of  little  nutritive  value, 
such,  for  example,  as  beef-tea. 

The  experiments  of  Pawlow^  have  placed  the  mode  of  action  of 
these  substances  in  a  clearer  light,  and  tend  to  enhance  our  sense  of 
their  importance.  They  appear  to  act  partly  through  the  organs  of 
taste,  in  part  reflexly,  and  in  part  also  by  a  direct  local  action  on 
the  stomach.  In  all  of  these  ways  the  appetite  is  aroused  and  the 
secretion  of  gastric  juice  promoted. ^  The  direct  irritant  effect  which 
some  of  them  have  upon  the  stomach  contra-indicates  their  use  in 
certain  forms  of  dyspepsia  in  which  the  mucous  membrane  is  in  a 
state  of  congestion  or  slight  catarrh.  Many  of  them,  too,  exert  a 
similar  influence  upon  the  organs  of  excretion,  and  for  that  reason 
they  should  be  avoided  by  patients  who  are  suffering  from  conges- 
tion of  the  kidneys  or  nephritis,  or,  indeed,  inflammation  in  any  part 
of  the  genito-urinary  tract. 

We  have  not  space  to  study  in  detail  the  chemistry  and  composi- 
tion of  the  vast  number  of  flavouring  agents  which  enter  into  the 
diet.  It  will  be  sufficient  for  us  to  glance  for  a  moment  at  some  of 
those  in  commonest  use. 

Mustard  is  derived  from  the  seeds  of  the  black  or  white  mustard- 
plant  (Brassica  nigra  and  alba).  The  seeds  of  the  white  plant  are  the 
larger.  They  contain  an  acrid  principle,  but  no  essential  oil.  The 
black  seeds  contain  a  substance  called  myronate  of  potash,  along 
with  a  ferment  (myrosin),  and  these,  when  moistened  with  water, 
interact,  producing  the  pungent  essential  oil  to  which  the  character- 
istic sharpness  of  mustard  is  due.  The  horse-radish  (Cochlearia 
armovacia)  contains  an  oil  similar  to  that  of  black  mustard. 

Mustard  flour  contains  from  15  to  25  per  cent,  of  fixed  oil,  0-5  to 
2  per  cent,  of  volatile  oil,  35  to  45  per  cent,  of  nitrogenous  matter, 
2  to  5  per  cent,  of  cellulose,  and  4  to  6  per  cent,  of  mineral  matter, 
along  with  a  little  starch  (Snyder). 

Black  pepper  is  derived  from  the  unripe  berries  of  the  Piper  nigrum  ; 
white  pepper  is  produced  from  the  ripe  fruit.     The  seeds  contain  an 

*  'Die  Arbeit  der  Verdauungsdriisen,'  Wiesbaden,  1898,  chapter  viii. 

^  More  recent  experiments  on  men  have  shown  that  the  effect  of  spices  on  the 
secretion  of  gastric  juice  is  very  variable  and  inconstant,  and  probably  depends 
to  some  extent  on  factors  which  vary  in  different  individuals.  On  the  other 
hand,  their  power  of  stimulating  the  movements  of  the  stomach  is  invariable 
(see  v.  Korczynski,  '  Ueber  den  Enifluss  der  Gewurze  auf  die  Sekretorische  und 
motorische  Tatigkeit  des  Magens,'  Wtencr  Klin.  Woch.,  1902,  xv.  468). 


286  FOOD  AND  DIETETICS 

essential  oil  and  an  alkaloid  (piperine),  both  of  which  contribute  to 
the  pungent  taste  of  the  substance.  Cayenne  pepper  is  derived  from 
the  pods  of  capsicum  ;  the  small  pods  constitute  chillies. 

The  basis  of  vinegar  is  acetic  acid.  Every  loo  c.c.  of  good 
vinegar  should  contain  5  grammes  of  the  acid,  calculated  in  the 
glacial  form.  In  genuine  vinegars  the  acetic  acid  is  produced  by 
the  oxidation  of  alcohol  by  a  fungus  (the  Mycoderma  aceti),  while  in 
wood  vinegar  it  is  produced  by  the  destructive  distillation  of  wood, 
the  product  being  often  coloured  by  the  addition  of  burnt  sugar. 
The  source  of  the  alcohol  in  genuine  vinegars  varies.  In  the  best 
varieties  weak  wines  are  the  source,  and  such  vinegars  retain  a 
certain  amount  of  *  bouquet,'  derived  from  the  wine.  Solutions  of 
alcohol  derived  from  the  fermentation  of  malt — dilute  beers,  in  fact 
— are,  or  ought  to  be,  the  source  of  malt  vinegar ;  but  this  term  is 
often  used  by  manufacturers  in  a  very  misleading  fashion,  for  in 
recent  years  dilute  spirit  derived  from  sugar  or  molasses  has  come 
much  into  use  as  a  substitute  for  malt.  It  can  scarcely  be  main- 
tained that  such  a  substitution  is  in  any  way  injurious  to  health. 
Vinegar  is  often  distilled,  in  order  to  make  it  keep  better.  The 
distillate  contains  the  acetic  acid,  along  with  traces  of  alcohol  and 
ether.  This  variety  is  said  to  be  very  popular  in  Scotland 
(Allen). 

In  addition  to  being  a  condiment,  vinegar  has  an  important  action 
in  softening  the  fibres  of  hard  meat  and  the  cellulose  of  green  vege- 
tables. Hence  its  use  with  such  articles  as  crab  and  its  addition  to 
salads.  Although  the  acetic  acid  which  vinegar  contains  is  ulti- 
mately oxidized  in  the  body,  with  the  production  of  alkaline  com- 
pounds, there  is  still  reason  to  believe  that  it  has  an  unfavourable 
influence  in  gout,  and  may  even  precipitate  an  attack  if  freely  in- 
dulged in. 

Ginger  is  the  root  of  a  plant  (Zingiber  officinale)  met  with  chiefly 
in  India.  It  contains  from  1-5  to  3  per  cent,  of  volatile  oil,  and 
about  3  per  cent,  of  fixed  oil,  along  with  a  large  amount  of  starch. 

Cinnamon  and  Cassia  are  derived  from  the  bark  of  several  species 
of  tropical  plants.     They  contain  volatile  and  fixed  oils. 

Cloves  are  the  dried  flower-buds  of  a  tropical  evergreen.  .  They 
contain  as  much  as  10  per  cent,  of  volatile  oil  and  a  good  deal  of 
tannin. 

Allspice,  or  pimento,  is  the  fruit  of  a  West  Indian  evergreen,  which 
contains  about  2*5  per  cent,  of  volatile  oil. 

Nutmeg  is  the  kernel  of  a  small  pear-like  fruit  which  grows  in  the 
East  Indies.     Mace  is  the  red  fleshy  mantle  which  envelops  the  seed. 


SPICES  AND  CONDIMENTS  287 

These  contain  about  25  per  cent,  of  fixed   and  2-5  to  5  per  cent. 
of  volatile  oils. 

It  only  remains  to  add  that  sugar  itself,  in  addition  to  its  value  as 
a  food,  is  one  of  the  most  important  of  the  condiments  in  common 
use,  and,  like  all  of  these,  is  able  to  stimulate  appetite  and  digestion 
if  used  in  moderation.  This  justifies  the  consumption  of  sweets  at 
dessert.  Chemical  substitutes  for  sugar  which  possess  its  flavouring 
qualities  without  its  food  value  are  saccharin  (benzoic  sulphamide) 
and  dulcin  (sucrol).  The  preparation  known  as  saxin  owes  its 
sweetness  to  saccharin.  Porcherine  is  another  powerful  artificial 
sweetener.  These  have  many  hundred  times  the  sweetening  power 
of  sugar,  but  are  of  no  use  as  foods.  They  are  used  to  replace  sugar 
as  a  flavourer,  chiefly  by  diabetic,  gouty,  and  obese  patients* 


t288  1 


CHAPTER  XVI 

MINEEAL  CONSTITUENTS  OF  THE  FOOD 

The  human  body  contains  about  7  pounds  of  mineral  matter,  of 
which  about  five-sixths  is  in  the  bones.  An  analysis  of  the  whole 
body  would  yield  about  5  per  cent,  of  ash.  It  is  obvious  from  this 
that  the  mineral  ingredients  of  the  diet  are  important  building 
material  for  the  body,  and  are  therefore  to  be  regarded  as  foods  in 
the  strictly  scientific  sense  of  the  term. 

The  chief  mineral  substances  required  in  the  food  are  sodium, 
potassium,  calcium,  magnesium,  and  iron,  along  with  phosphorus, 
chlorine,  sulphur,  and  traces  of  silica,  fluorine,  and  iodine. 

So  necessary  are  these  for  maintaining  intact  the  fabric  of  the 
body  that  death  ensues  within  about  a  month  if  the  supply  of  them 
is  entirely  cut  off,  even  although  all  the  other  constituents  of  a  normal 
diet  are  supplied  as  before. 

Recent  estimates  of  the  amount  of  some  of  the  chief  mineral 
ingredients  of  the  diet  required  per  day  are  as  follows : 


Grammes. 
Phosphoric  acid  ..          ..     3  to  4 
Sulphuric        ,,     . .         ,.     2  ,,  3J 
Potassium  oxide  . .         . .     2  , ,  3 
Sodium  4  .,  6 


Grammes. 
Calcium  oxide. .         ,,        i  to  i'5 
Magnesium  oxide       ..     0*3  ,,  0*5 
Chlorine  ..         ..        6  ,;  8 

Iron       ..         ..         ..o-oo6,,  0012 


It  being  granted,  then,  that  the  mineral  constituents  of  the  food 
are  important  as  tissue-builders,  the  question  may  next  be  asked, 
Are  they  of  any  value  as  sources  of  heat  or  energy  ?  As  regards  the 
former,  the  reply  is  in  the  negative.  The  mmeral  substances  in  the 
food  enter  the  body  in  a  form  too  highly  oxidized  to  be  capable  of 
yielding  any  heat  in  the  tissues. 

As  regards  the  question  of  supplying  energy,  the  reply  is  more 
doubtful.  It  is  true  that  the  substances  under  consideration  cannot 
yield  energy  by  oxidation  in  the  way  that  the  proteins,  fats  and 
carbohydrates  do,  but  there  is  reason  to  believe  that  they  are  able  to 
act  indirectly  as  sources  of  energy  in  virtue  of  the  osmotic  properties 


MINERAL  CONSTITUENTS  OF  THE  FOOD        289 

which  they  possess.  It  is  found, ^  for  example,  that  ordinary  soup, 
by  reason  of  its  salts,  possesses  an  osmotic  pressure  of  from  7  to  9 
atmospheres.  Now,  the  body  fluids  have  an  osmotic  pressure  of 
only  6  atmospheres,  and  thus  half  a  pint  of  soup  will  raise  the  osmotic 
pressure  in  the  body  by  fully  half  an  atmosphere.  In  this  way  absorp- 
tion and  the  diffusion  of  the  body  fluids  is  aided,  and  such  an  action  is 
equivalent  to  the  supply  of  a  certain  amount  of  energy  to  the  body. 
Thus  it  is  that  the  mineral  constituents  of  the  diet  may  claim  to 
rank  as  *  foods '  on  two  grounds  :  they  are  builders  of  tissue  and 
they  are  sources  of  potential  energy  as  well. 

We  have  next  to  inquire.  What  amount  of  mineral  matter  must  be 
supplied  to  the  body  daily?  To  this  inquiry  no  definite  reply  is 
forthcoming.  We  cannot  tell  how  much  of  these  substances  is 
required  for  healthy  nutrition  in  as  precise  a  manner  as  we  can 
calculate  the  need  for  carbon  or  for  nitrogen,  mainly  for  this  reason — 
that  many  of  the  waste  mineral  matters  of  the  body  are  excreted  by 
the  intestine,  and  we  have  no  means  of  telling  what  proportion  of 
these  has  merely  escaped  absorption,  and  how  much  has  been 
excreted  from  the  blood  after  playing  a  part  in  metabolism.  This, 
however,  one  can  say,  that  the  amount  of  mineral  matter  found  in  an 
ordinary  mixed  diet  is  sufficient — nay,  much  more  than  sufficient — 
for  all  the  needs  of  the  body,  and  that  amount  is  about  20  grammes, 
eKclusive  of  such  arbitrary  additions  as  salt.  * 

As  regards  the  form  in  which  the  mineral  constituents  enter  into 
an  ordinary  diet,  it  may  be  said  that  many,  if  not,  indeed,  most  of 
them,  are  in  a  state  of  organic  combination.  Thus,  we  find  calcium 
and  phosphorus  organically  combined  in  milk,  iron  in  yolk  of  egg 
and  in  meat,  sulphur  in  all  protein-containing  foods,  and  so  on.  It 
would  appear,  although  the  reason  for  it  is  obscure,  that  such 
organic  mineral  compounds  are  of  special  value  in  nutrition.  It 
cannot  be  maintained,  however,  that  it  is  only  in  such  forms  that 
mineral  matter  can  find  access  to  the  blood.  Experiment  has  shown 
that  even  such  a  substance  as  carbonate  of  lime  is  absorbed  to  some 
extent,  for  its  administration  is  followed  by  an  increased  excretion  of 
calcium  in  the  urine,^  and  the  success  which  attends  the  treatment  of 
cases  of  chlorosis  by  purely  inorganic  preparations  of  iron  compels 
us  to  believe  that  the  metal  is  capable  of  being  absorbed  in  that 
form. 

^  Koeppe,  '  Die  Bedeutung  der  Salze  als  Nahrungsmittel ':  68ten  Versamm. 
Deut.  Naturforscher  und  Arzte.     Frankfurt,  1896,  Teil  ii.,  Halfte  ii.,  p.  80. 

^  Bunge  is  of  opinion  that  lime  and  iron  are  the  only  mineral  ingredients  of  the 
diet  which  are  ever  likely  to  be  present  in  too  small  amount  {Zeit.  f.  Biolog., 
1904,  xlv.  (N.F.,  27),  p.  53^) 

*  Strauss,  Zeit.  f.  Klin.  Mtd.,  1897,  xxxi.  493 

19 


290  FOOD  AND  DIETETICS 

Notwithstanding  these  facts,  it  was  found  by  Lunin  that  mice  fed 
on  desiccated  milk  lived  quite  healthily,  whereas  other  mice  which 
were  given  pure  casein  plus  all  the  salts  of  milk  in  an  inorganic 
form  died.^  No  explanation  of  such  results  can  be  given,  but  they 
show  that  the  form  in  which  the  mineral  constituents  of  the  food  are 
presented  to  us  is  by  no  means  a  matter  of  indifference. 

We  may  now  pass  on  to  consider  the  amount  and  kind  of  the 
mineral  constituents  met  with  in  different  articles  of  diet.  It  would 
serve  no  useful  purpose,  however,  to  present  the  reader  with 
analytical  tables  professing  to  exhibit  the  precise  percentage  of  the 
various  components  of  the  ash  of  different  foods,  for  the  reason  that 
these  are  subject  to  very  great  fluctuations  in  kind  and  amount. 
This  is  specially  true  of  vegetable  foods,  on  the  mineral  ingredients 
of  which  the  mode  of  cultivation  and  nature  of  the  soil  have  such  a 
marked  influence.  It  will  be  more  useful  to  take  up  the  principal 
mineral  substances  required  by  the  body  separately,  and  to  point  out 
in  general  terms  what  articles  of  diet  are  richest  in  them.  Let  us 
begin  with  calcium. 

Calcium. — It  has  been  calculated,  from  analyses  of  human  milk, 
that  an  infant  requires  about  J  gramme  (5  grains)  of  lime  daily.  The 
adult,  owing  to  cessation  of  the  growth  of  the  bones,  requires 
relatively  less.  Deficiency  of  lime  in  the  food  of  an  infant  leads  to 
softening  of  the  bones ;  but  this,  though  an  element  in  rickets,  is 
not  really  the  root  of  that  disease,  for  nothing  is  more  certain  than 
that  an  infant  may  suffer  from  rickets  even  although  there  has  been 
an  actual  excess  of  lime  salts  in  its  food. 

In  later  life  various  pathological  conditions  have  been  ascribed  to 
an  excessive  consumption  of  calcium  in  the  food.  Amongst  these 
are  calculus,  atheroma^  and  other  calcareous  degenerations,  and 
habitual  constipation.  It  must  be  admitted,  however,  that  there  is 
but  little  real  evidence  for  such  views.  It  is  exceedingly  doubtful 
whether  the  intestine  ever  absorbs  more  of  any  mineral  substance 
than  the  tissues  require,  and  if  there  is  a  tendency  to  the  accumula- 
tion of  such  substances  in  any  particular  situation,  the  fault  must  be 
ascribed  to  some  local  change  in  the  tissues,  rather  than  to  any 
undue  increase  of  absorption. 
Of  common  articles  of  diet,  the  richest  in  calcium  is  milk.     It 

1  See  also  Socin,  Zeit.  f.  Physiolog.  Chem.,  1891,  xv.  93. 

^  Ruinpf,  Berliner  Klin.  Wochensch.,  1897,  xxxiv.  265.  The  author  recom- 
mends atheromatous  subjects  to  adopt  a  diet  poor  in  calcium  salts,  such,  for 
example,  as  bread,  fish,  meat,  apples  and  potatoes.  See  also  1  Jirschberg 
[Berliner  Klin.  Wochensch.,  No.  46,  1911),  who  advises  that  the  intake  ul  calcium 
should  be  reduced  in  cases  of  spondylitis  and  arthritis  deformans. 


LIME  sgz 

contains  i|  grammes  of  lime  in  every  litre;  or,  put  otherwise,  there 
is  more  Imie  in  a  pint  of  milk  than  in  a  similar  quantity  of  lime- 
water.  Next  to  milk  come  eggs,  then  the  cereals — and  especially 
rice — and  then  some  vegetables,  such  as  radishes,  asparagus  and 
spinach.  Hard  waters  also  must  be  regarded  as  important  dietetic 
sources  of  calcium. 

Foods  poor  in  lime  are  meat  (but  only  if  derived  from  a  fully- 
grown  animal — veal,  for  example,  being  comparatively  rich  in 
calcium^),  fish,  bread,  fruits  and  potatoes. 

The  importance  of  milk  and  eggs  as  foods  for  growing  children 
will  be  apparent  from  these  facts,  while  if  one  should  for  any  reason 
desire  to  construct  a  dietary  containing  a  minimum  of  lime,  it 
would  be  well  to  draw  its  ingredients  from  the  members  of  the 
second  group. 

Magnesium  is  usually  present  in  foods  in  the  same  proportion  as 
calcium.  There  are  exceptions  to  this  rule,  however,  for  in  milk 
magnesium  is  less,  and  in  meat  rather  more,  abundant  than  calcium, 
while  in  bread  there  is  actually  five  times  as  much  of  the  former  as 
of  the  latter.2 

Iron  is  one  of  the  mineral  constituents  of  the  diet  of  which  one  may 
say  that  it  is  always  present  in  an  organic  form.  It  is  also  mainly 
excreted  in  the  faeces,  and  this  fact  has  led  to  great  difficulty  in 
attempting  to  estimate  the  amount  of  it  required  by  the  body  daily. 
Roughly  speaking,  there  are  about  lo  milligrammes  of  the  metal 
contained  in  an  ordinary  mixed  diet  (Stockman),  and  that  quantity 
must  therefore  be  regarded  as  sufficient  to  meet  all  physiological 
demands.^ 

It  is  difficult  to  give  precise  figures  as  to  the  amount  of  iron 
present  in  different  articles  of  diet.  In  animal  foods  it  depends  very 
much  on  whether  the  animal  was  bled  or  not,  while  in  vegetable 
foods  it  varies  very  greatly  with  the  amount  of  iron  in  the  soil. 
Bunge^  arranges  some  common  foods  in  the  order  of  their  richness 
(not  the  richness  of  their  ash)  in  iron  as  follows :  Spinach,  yolk  of 
egg,  beef,  apples,  lentils,  strawberries,  white  beans,  peas,  potatoes, 
wheat. 

^  See  Katz,  Pfluger's  Archiv,  1896,  Ixiii.  i. 

'  See  Richet's  '  Dictionary  of  Physiology.' 

'  A  study  of  several  typical  American  diets  (United  States  Department  of 
Agriculture,  OfiSce  of  Experiment  Stations,  Bulletin  185,  1907)  shows  that  the 
majority  yield  from  11  to  19  milligrammes  of  iron  per  day. 

*  Bunge,  '  Der  Kalk  und  Eisengehalt  uoserer  Nahrung,'  Zeit.  /.  Biolog.,  1904 
(N.F.  45),  xxvii.  532. 


292  FOOD  AND  DIETETICS 

Boussingault*  gives  the  following  proportions  of  iron  in  loo  parts 
of  the  following  foods  examined  in  the  fresh  condition : 

PROPORTION  OF  IRON  PER  loo  PARTS  OF  FRESH  SUBSTANCE. 

Blood  of  ox 003750 

,,       pig  . .         ..         . .         .  •         ..  006340 

Beef    ..         ..         ..  000480 

Veal 000270 

White  fish 000150 

Egg 000570 

Wheaten  bread         000480 

Haricots        000740 

Oats 001310 

Lentils  000830 

Potatoes         000160 

Milk o-ooiSo 

Carrots  000090 

Maize 000360 

Rice 000150 

Apples  ..  ..  ..  ..  ..  000200 

Spinach  0-00450 

Cabbage        000390  "j 

Burgundy 001090  >  in  one  litre. 

Beer    ..         ..         ..         ..         ..         ••  0*00400 J 

Stockman  has  pointed  out'  that  these  results  are  too  high,  probably 
from  faulty  methods  of  analysis.  He  gives  the  following  amounts  of 
iron  in  some  common  foods : 


I  pint  of  milk 

100  grammes  of  oatmeal   . . 
300        „  fine  bread 

280        „  common  bread 

120        „  beef-steak 


22  milligrammes  iron. 

1-8 

47 


From  the  results  available,  it  may  be  concluded  that  beef  and 

yolk  of  eggS  are  foods  richest  in  iron,  while  milk  and  its  derivatives, 
such  as  cheese,  are  amongst  the  poorest ;  but  even  5  pints  of  milk 
would  supply  the  10  milligrammes  of  metal  required  in  the  daily 
diet.  Oatmeal  and  Egyptian  lentils  are  amongst  the  richest  in  iron 
of  vegetable  foods,  but  bread,  rice,  potatoes  and  spinach  also  contain 
a  good  deal.  As  regards  an  ordinary  mixed  diet  it  may  be  said  that 
the  amount  of  iron  which  it  contains  is  roughly  proportional  to  its 
richness  in  protein,  for  these  two  constituents  tend  to  run  parallel  to 
each  other.  It  should  be  noted  that  the  iron  contained  in  haemoglobin 
and  its  derivatives  is  very  ill  absorbed.*    It  is  all  the  more  necessary 

I  Comptes  Rendus,  1872,  Ixxiv.  1355. 

*  Stockman  (R.  ),/ow;-«.  of  Physiolog.,  1895,  xviii.  484.  and  1897,  ^^i-  55  ;  sdso  Brit. 
Med.  Journ.,  1895,  ii.  1473.  For  later  analyses  see  '  Iron  in  Food  '  (United  States 
Department  of  Agriculture,  Office  of  Experiment  Stations,  Bulletin  185,  1907). 

*  See  Katz,  Archiv  f.  d.  Gesam.  Physiolog.,  1896,  Ixiii.  i  ;  also  Hairtung,  Ztit.  /. 
Biolog..  1902,  xliii.  195. 

*  V.  Starck,  Deut.  Med.  Wochensch.,  1898,  x\i\ .  805. 


IRON  293 

to  point  this  out,  as  haemoglobin  preparations  are  beginning  to  find 
a  place  in  the  treatment  of  anaemia. 

Amongst  beverages,  some  mineral  waters — e.g.,  Kronthal  (green 
label) — contain  a  good  deal  of  iron,  and  tea-leaves  also  are  very  rich 
in  it,  but  probably  littl^of  the  metal  finds  its  way  into  the  infusion. 
Wines  are  poor  in  iron,  even  the  so-called  ferruginous  varieties 
having  but  a  small  proportion. 

That  the  habitual  consumption  of  foods  poor  in  iron  may  lead  to 
anaemia  is  possible,  though  it  is  difficult  to  imagine  a  diet  that  would 
not  contain  the  small  amount  of  the  metal  required  daily.  Verdeil 
and  Subbotin,  however,  have  certainly  found  that  the  ash  of  the 
blood  of  dogs  fed  on  meat  contained  much  more  iron  than  that 
of  animals  nourished  on  bread ;  and  V.  Hoesslein  has  shown  that 
if  young  animals  receive  only  as  much  iron  as  adults  they  become 
anaemic. 

On  the  other  hand,  once  any  marked  deficiency  of  iron  in  the 
blood  exists,  it  is  almost  impossible  to  make  it  good  by  merely 
dietetic  means  ;  for  no  food  is  rich  enough  m  iron  salts  to  be  able  to 
accomplish  the  object  in  view.  Hence,  a  knowledge  of  the  amount 
of  iron  contained  in  different  foods  is,  after  all,  of  but  little  thera- 
peutic value. 

Sodium  and  Potassium. — Sodium  is  required  in  the  body  for  the 
proper  constitution  of  its  fluids ;  potassium  for  the  construction  of 
cells,  and  specially,  perhaps,  of  the  red  blood  cells  and  the  muscles. 
Young  animals  deprived  of  potassium  do  not  develop  good  muscles. 
As  regards  the  amount  of  sodium  and  potassium  contained  in  different 
foods,  it  may  be  said  that  the  vegetable  group  is  richest  in  the 
latter,  and  the  animal  group  in  the  former. 

Bunge  gives  the  following  table  of  proportions: 

To  I  equivalent  of  sodium  there  is — 

In  yolk  of  egg  . .         . .         . .  i    equivalent  of  potassium. 

,,   milk  ..         ..         ..         ..  o"8  to  6    equivalents  of  potassium. 

»  veal 4  „  „ 

„   wheat  12,,  23  „  „ 

„   potatoes       31  „  42  »  II 

>,  peas 44,,  50  „  ,, 

Sodium  is  chiefly  taken  in  the  form  of  sodium  chloride,  or 
common  salt.  Of  this  most  people  consume  about  20  grammes 
daily,  which  is  probably  at  least  ten  times  as  much  as  is  really 
necessary  to  meet  the  needs  of  the  body.     There  are  not  wanting 


294  FOOD  AND  DIETETICS 

people  who  maintain  that  this  excessive  consumption  of  salt  Is  not 
only  needless,  but  even  harmful,  as  tending  to  throw  a  strain  upon 
the  kidneys,  which  may  end  in  injuring  them  permanently,  and  as 
perhaps  contributing  to  the  production  of  gout,  diseases  of  the  skin, 
and  chronic  catarrhs. ^ 

These  views,  however,  are  not  yet  proven.  In  may  be  admitted 
— for  the  experience  of  those  who  refuse  to  add  any  salt  to  their 
food  amply  proves  it — that  the  amount  of  sodium  chloride  contained 
in  a  natural  form  in  ordinary  foods  is  quite  sufficient  for  our 
needs;  but  there  is  no  proof  that  an  extra  addition  of  salt  in  the 
form  of  a  condiment  is  really  injurious  to  health.  On  the  other 
hand,  it  is  equally  far  from  being  proved  that  such  addition  conduces 
in  any  way  to  the  well-being  of  the  body.  It  has  been  asserted,  for 
instance,  that  the  addition  of  salt  to  the  food  aids  digestion  (Ogata), 
but  more  recent  and  exact  experiments  have  shown  that — in  health, 
at  least,  and  in  moderate  doses — salt  has  very  little  real  influence 
on  digestion  at  all,  while  in  large  quantities  it  actually  delays  the 
process.^  If,  moreover,  sodium  chloride  is  entirely  removed  from 
the  food,  the  secretion  of  hydrochloric  acid  is  lessened,  or  even 
arrested  altogether,  and  upon  this  basis  it  has  been  urged  that  one 
should  limit  the  use  of  salt  in  cases  of  hyperacidity  of  the  stomach. 
Where,  on  the  other  hand,  appetite  is  poor  and  digestive  power 
feeble,  the  moderate  use  of  salt  in  the  food  may  act  as  a  digestive 
stimulant  in  the  same  way  as  any  other  condiment.  There  is  also 
reason  to  believe  that  it  may  slightly  aid  the  absorption  of  food.^ 

On  the  general  processes  of  nutrition  in  the  body,  salt  seems  to 
be  equally  devoid  of  any  pronounced  effects.  On  the  one  hand  it 
has  been  maintained  that  it  acts  as  a  cell  stimulant,*  while  on  the 
other  it  has  been  denied,  on  seemingly  equally  good  grounds,  that  it 
has  any  distinct  influence  on  metabolism  at  all.  The  latest  and 
most  conclusive  experiments*  tend  to  show  that  any  action  salt  may 
have  is  in  the  direction  of  lessening  nitrogenous  waste,  provided  a 
suffiiiency  of  water  is  supplied  at  the  same  time. 

The  craving  for  salt  as  an  addition  to  the  diet  seems  to  be  specially 

1  See  a  paper  by  R.  Ackerley,  '  Saline  Waters,  and  the  Use  and  Abuse  of 
Common  Salt,"  Proc.  Roy.  Soc.  of  Med.,  February,  1910. 

'  See  Pawlow,  *  Die  Arbeit  der  Verdauungsdrusen,'  and  Schiile,  Ztit.f.  Klin. 
Med.,  1895,  xxviii.  492,  and  1896,  xxix.  49. 

*  Gabriel,  Zeit.  f.  Biolog.,  1892,  xxix.  554. 

*  Gamier  and  Lambert,  Archives  de  Physiolog.,  1898,  xxx.  421. 

*  Walther  Straub,  Zeit.  f.  Biolog.,  1898,  xxxvii,  527.  For  a  recent  review  of 
the  whole  subject,  see  Belli,  Zeit.  f.  Biolog.,  1904  (N.F.  27),  x\\.  182. 


COMMON  SALT 


295 


strong  amongst  vegetable-feeders.  An  ingenious  explanation  of  this 
fact  has  been  advanced  by  Bunge  on  the  lines  that  the  large  propor- 
tion of  potassium  in  vegetable  substances  would  tend  to  drive  all 
sodium  out  of  the  body  were  the  latter  not  constantly  reinforced  by 
the  addition  of  salt  to  the  food.  This  theory  has  been  strongly 
criticised  by  Forster  and  others,  and  it  is  doubtful  if  it  can  be 
regarded  as  tenable — -at  least,  in  the  extreme  form  in  which  it  was 
brought  forward  by  its  distinguished  author.  Whatever  the  explana- 
tion, however,  the  fact  remains  that  the  artificial  addition  of  salt  is 
apparently  more  necessary  in  the  case  of  people  who  live  mainly  on 
vegetable  products  than  in  those  who  consume  a  mixed  diet. 

Phosphorus. — The  importance  of  phosphorus  as  a  building  material 
in  the  body  can  scarcely  be  overrated.  Wherever  growth  is  most 
active  there  most  phosphorus  is  found.  It  enters  into  the  composi- 
tion of  all  cell  nuclei,  and  it  is  abundantly  present  in  the  bones  and 
in  the  central  nervous  system.  One  would  naturally  expect,  there- 
fore, that  wherever  the  building  up  of  such  tissues  is  going  on  rapidly 
a  large  supply  of  phosphorus  will  be  required  in  the  food,  and  it  is 
not  surprising  to  find  that  the  development  of  young  animals  which 
are  deprived  of  it  is  apt  to  be  seriously  impaired.  Hence  the  great 
importance  of  a  due  supply  of  phosphorus  in  the  food  of  growing 
children. 

The  percentage  of  phosphoric  acid  (P2O5)  in  some  fresh  foods  is 
as  follows '} 


Vegetable. 


Animal. 


Carrot 

.         . .     0036  per 

cent. 

Pork 

0160  per  cent 

Turnip 

..     0058 

Milk 

0220         ,, 

Cabbage 

>•         ..     0089 

Beef 

0285 

Potato 

..     0140 

Eggs 

0-337 

Chestnuts 

.,     0200 

White  cheese     . . 

0-374 

Barleymeal 

..     0230 

Mutton    . . 

0425 

Haricots 

..     0924 

Gruyere  cheese  . . 

1353 

The  superiority  of  most  animal  foods  in  respect  of  this  constituent 
is  at  once  apparent. 

The  phosphorus  contained  in  foods  is,  for  the  most  part,  present 
in  an  organic  form  of  combination,  sometimes  of  a  very  complex 
sort,  but  in  part  also  in  an  inorganic  form  as  phosphates  of  the 
alkalis  or  earths. 


*  Giraxd,  Comptes  Ren  Jus,  1896.  cxxii   1387. 


age  FOOD  AND  DIETETICS 

There  is  reason  to  believe  that  the  organic  forms  are  the  more 
valuable  for  contributing  to  the  growth  and  repair  of  tissue.^ 
Examples  of  these  are  the  chemical  substances  nuclein,  lecithin, 
glycero-phosphoric  acid,  phospho-carnic  acid  and  phytin,  all  of  which 
are  probably  valuable  dietetic  sources  of  the  element.  The  foods 
richest  in  these  are  such  articles  as  yolk  of  egg,  thymus,  fish-roe, 
calves'  brains,  and  the  germ  of  wheat.  Phjrbin  is  particularly  rich 
in  organic  phosphorus.  It  is  an  acid  calcium  magnesium  salt  of 
anhydrous  oxymethylene  diphosphoric  acid  contained  in  the  seeds 
and  tubera  of  plants.  Being  readily  assimilated  it  is  a  valuable 
means  of  enriching  the  diet  in  phosphorus, 

It  is  doubtful,  on  the  other  hand,  whether  the  inorganic  com- 
pounds containing  phosphorus  are  of  much  value  in  the  body. 
They  seem  to  be  almost  immediately  excreted  by  the  kidney  or 
bowel,  probably  without  exercising  any  important  influence  on 
metabolism. 

Cere  bos  salt  consists  of  a  mixture  of  4  parts  of  calcium  and 
magnesium  phosphates  with  96  parts  of  common  salt.  The  phos- 
phates in  such  a  preparation  are  present  in  a  purely  inorganic  form, 
and  are  therefore  of  doubtful  utility.  In  any  case  the  recommenda- 
tion of  such  preparations  is  based  upon  the  groundless  assumption 
that  an  ordinary  mixed  diet  is  too  poor  in  phosphorus  to  be  able 
adequately  to  supply  our  need  of  that  substance.  It  has  been 
calculated  that  less  than  2  grammes  of  phosphates  are  required  to 
meet  the  daily  needs  of  the  body  and  that  an  average  mixed  diet 
contains  from  3  to  5  grammes  or  more  (Snyder).  It  may  be 
remarked  in  this  connection  that  we  know  of  no  diseased  condition, 
which  can  be  clearly  traced  to  a  deficiency  of  phosphorus  in  the  diet. 
This  is  true,  indeed,  not  of  phosphorus  alone,  but  of  all  the  other 
mineral  ingredients  of  the  diet  with  the  exception  of  iron,  and  possibly 
also  of  calcium.  A  deficiency  of  iron  in  the  food  may,  as  already 
remarked,  lead  to  the  development  of  anaemia,  and  too  little  lime 

^  Keller,  however,  in  a  review  of  the  whole  question  (Zeit.  /.  Dial,  und  Physik. 
Thcrapie.  1901,  iv.  669),  concludes  that  although  phosphorus  in  organic  com- 
bination is  fully  absorbed  and  assimilated,  yet  it  has  not  been  conclusively 
proved  that  it  is  more  useful  in  this  form  than  the  inorganic  phosphates,  and  still 
less  that  organic  combinations  of  phosphorus  are  essential  for  life  and  growth. 
Hart,  McCollum,  and  Fuller,  also,  found  in  experiments  on  pigs  {Amer.  Joiirn.  of 
Physiol.,  1908-09,  xxiii.  246)  that  the  administration  of  calcium  phosphate  could 
prevent  the  effects  of  a  low  phosphorus  ration,  and  gave  as  good  results  in  this 
respect  as  such  an  organic  phosphorus  compound  as  phytin.  On  the  other  hand, 
Tunnicliffe  {Arckiv.  internal,  de  Pharmacodynamie  et  de  Thera^ie,  1906,  xvi.  207) 
found  that  the  addition  of  calcium  phosphate  to  the  food  of  children  did  not 
increase  the  amount  of  phosphorus  assimilated  or  retained,  whereas  the  addition 
of  an  organic  phosphorus  compound  did. 


PHOSPHATES  297 

in  the  food  may  cause  the  bones  of  children  to  become  soft ;  but 
with  these  rather  doubtful  exceptions  it  may  be  safely  assumed  that 
any  ordinary  diet  will  amply  provide  for  all  the  mineral  matter  we 
require.  If  one  should  for  any  reason  think  it  advisable  to  increase 
the  proportion  of  phosphorus  in  the  food,  it  would  be  wiser  to  have 
recourse  to  those  articles  already  mentioned  in  which  it  is  present  in 
an  organic  form,  rather  than  to  pour  into  the  body  inorganic  com- 
pounds which  will  probably  be  excreted  from  it  just  as  they  entered. 
That  such  organic  forms  are  well  absorbed  there  is  now  no  doubt. ^ 

Oxalic  acid,  though  not  strictly  speaking  a  mineral  substance,  may 
be  conveniently  considered  here,  for  it  is  usually  present  in  the  diet 
in  the  form  of  oxalate  of  lime.  Esbach  gave  the  following  table  of 
the  amount  of  oxalic  acid  in  different  articles  of  food  : ' 

Per  r.ooo. 

Black  tea  infused  5  minutes  ..         ..  2*060 

Cocoa-powder  ..         ..         ..         ..  3-5:^0  to  4500 

Pepper  3250 

Coffee 0127 

Parsley  . .         . .  . .  . .  . .  o  006 

Haricots  0312 

Common  beans         ..         ..         ..         ..  0158 

Potatoes  ..         ..         ..         ..         ..  0046 

Good  bread    ..         ..         ..         ..         ..  0047 

Crust 0130 

Crumb  ..         ..         ..         ..         ..  0120 

Buckwheat  flour       ..  ..  ..  ..  0171 

Barleymeal     ..  ..  ..  ..  ..  0039 

Maize  flour     ..         ..         ..         ..         ..  0033 

Sorrel  '..  2740  to  3630 

Spinach  ..         ..         ..         ..         ..  i9ioto3-!^o 

Rhubarb         ..         ..  2466 

Brussels  sprouts        ..  ..  ..  ..  0020 

Cauliflower    . .         . .         . .         . .         . .  o  003 

Beetroot  . .  . .         . .  . .  . .  0390 

French  beans  ..         ..         ..         ..  o  060  to  o  2H 

Salsifies  . .         . .         . .         . .         . .  0070 

Tomatoes       ..         ..  0002  to  005a 

Carrots  0027 

Chicory  ..         ..         0103 

Dodder  ..         ..         ..         ..         ..  0045 

Endive  ..         ..         ..         ..         ..  0017 

Lettuce  ..         ..         ..         ..         ..  0016 

Dried  figs        ..         ..         ..         ..         ..  0^70 

Currants         ..         ..         ..         ..         ..  0130 

Prunes  ..  ..  ..  ..  ..  o  120 

Gooseberries  . .         . .         . .         . .         . .  0070 

Plums  . .  . .  . .  . .  . .         . .  0070 

Raspberries    . .         . .         . .         . .         . .  0062 

Oranges  ..         ,.  ..  ..  ..  0030 

Lemons  ..  ..  ..  ..  ..  0030 

Cherries  ..  ..  ..  ..  ..  0025 

Strawberries  ..         ..         ..         ..         ..  0012 

1  See  Bergell,  Fortschr.  der  Med.,  1898,  xvi.  i. 

*  For  other  estimations  see  a  paper  by  ApoUina,  '  Ueber  die  Oxalsaure  im 
Organismus, '  B#»'i«».  Klin.  Wochensch.,  1901,  xxxviii.  544. 


298  FOOD  AND  DIETETICS 

It  will  be  observed  from  the  table  that  oxalic  acid  occurs  in 
relatively  large  amounts  in  tea,  cocoa,  spinach,  rhubarb,  sorrel,  and 
pepper.  Tomatoes  are  sometimes  said  to  be  rich  in  it,  but  this 
would  appear  to  be  an  error.  Their  sour  taste  is  due  to  the  presence 
of  citric  acid.  An  animal  diet  diminishes  the  excretion  of  oxalic 
acid  owing  to  the  small  amount  of  it  which  animal  foods  contain.^ 

There  would  seem  to  be  little  doubt  that  the  consumption  of  foods 
rich  in  oxalic  acid  may  be  a  cause  of  the  production  of  oxalic 
calculus.  Dr.  Prout,  for  example,  states  that  he  has  seen  well- 
marked  instances  in  which  an  oxalate  of  lime  nephritic  attack  has 
followed  the  free  use  of  rhubarb  (in  the  shape  of  tarts,  etc.), 
particularly  when  the  patient  has  been  in  the  habit  at  the  same  time 
of  drinking  hard  water.  On  the  other  hand,  the  condition  of  so- 
called  oxaluria  seems  to  have  no  relation  to  the  amount  of  oxalates 
in  the  diet,  but  to  be  merely  a  variety  of  acid  dyspepsia. 

Sulphur  is  present  in  the  food  almost  entirely  in  a  state  of  organic 
combination — chiefly  in  proteins.  The  amount  of  it  present  in  these 
varies  considerably,  as  is  shown  by  the  following  analyses  of  dry 
proteins.2     There  is  in — 

Dried  egg-white  ..  ..  ..  ..     iSo  per  cent. 

,,      syntonin  .,  ..  ..  ..     iSo         ,, 

„      albumin  of  wheat  ..  ..  ..155         ,, 

„  ,,  peas  ,.  ..  ..     0*40         ,, 

„     gluten    ..         ..  ..  ..  ..     070        „ 

We  know  nothing  of  the  advantages  or  otherwise  of  an  increase 
or  diminution  of  sulphur  in  the  food. 

CMorine  is  taken  in  almost  entirely  in  the  form  of  sodium  chloride, 
or  common  salt.  Except  as  a  source  of  hydrochloric  acid,  nothing 
is  known  of  its  uses  in  the  body,  but  the  peculiar  behaviour  of  the 
chlorides  in  some  acute  fevers  would  point  to  some  special  rdle 
attaching  to  them  in  metabolism. 

Iodine  is  present  in  small  quantities  in  fish.*  Thus,  herring  con- 
tain 2  milligrammes  per  kilo,  mussels  i-g  milligrammes,  salmon  1-4, 
ling  and  cod  1-2,  and  oysters  1-2.  The  only  situation  in  the  body  in 
which  this  element  has  been  detected  is  the  thyroid  gland,  and  the 
significance  of  its  presence  in  the  food  is  as  yet  quite  obscure, 
though  it  may  one  day  prove  to  be  of  some  importance. 

Fluorine  and  silica  are  present  in  the  body  in  small  quantities, 
chiefly  in  the  teeth  and  bones.  Vegetable  foods,  and  especially  the 
cereals,  are  their  most  abundant  source  in  the  diet. 

*  J.  C.  Dun\op,  Journal  oj  Pathology  and  Bacteriology,  1896,  iii.  389. 
■  •  R'chet's  '  Dictionary  of  Physiology.' 
»  See  Lancet,  1899,  ii.  1030  (abstract). 


ACIDITY  AND  ALKALINITY  IN  FOODS 


299 


The  question  of  the  acidity  or  alkalinity  of  foods  may  be  con- 
veniently dealt  with  here.  According  to  the  reaction  of  their  ash, 
foods  may  be  divided  into  three  groups  :i  (i)  Acid  foods,  i.^.,  those 
which  leave  on  incineration  an  acid-reacting  ash ;  (2)  neutral  food, 
with  neutral  ash  ;  and  (3)  alkaline  foods,  the  ash  of  which  is  alkaline 
in  reaction. 

Examples  of  these  groups,  arranged  in  the  order  of  their  acidity 
or  alkalinity  respectively,  are  as  follows  : 

Acid  Foods. 
Oats. 
Barley. 
Beef. 
Wheat 
Eggs. 
Rice. 
Maize. 


Wright  is  of  opinion  that  the  exclusion  from  the  diet  of  a  sufficient 
quantity  of  '  alkaline '  foods  leads  to  the  development  of  scurvy  and 
other  diseases  characterized  by  a  diminution  of  blood  coagulability. 
It  is  not  improbable,  also,  that  the  proportion  of  acids  or  alkalies  in 
foods  may  have  important  bearings  on  gout,  but  a  discussion  of  the 
question  would  lead  us  into  the  sphere  of  too  many  controversial 
matters.  At  all  events,  it  is  probably  safest  to  allow  the  '  alkaline 
foods  '  to  predominate  to  some  extent  in  the  diet. 

1  Wright,  'On  the  Pathology  and  Therapeutics  of  Scurvy,'  Army  Medical 
Reports,  1895,  xxxvii.  394.  It  must  be  pointed  out  that  the  reaction  of  the  ash 
of  foods  still  requires  elucidation.  I  have  not  been  able  to  find,  for  example, 
that  meat  leaves  an  acid-reacting  ash,  although  this  may  be  due  to  the  blood 
contained  in  the  meat.  For  a  discussion  of  the  question,  see  Sherman's  '  Food 
Products'  (Macmillan  Co.,  1914),  p.  352. 


Neutral. 

A  Ikaline. 

Sugar. 

Carrot. 

Vegetable  oils. 

Turnip. 

/^mal  fats. 

Potato. 

Onion. 

Milk. 

Blood. 

Peas. 

Lemon-juice. 

Orange-juice. 

Beans. 

[joo  ] 


CHAPTER  XVII 
WATER  AND  MINERAL  WATERS 

About  two-thirds  of  the  total  weight  of  the  body  is  made  up  of 
water.  The  importance  of  water  as  a  tissue-builder  and  its  right 
to  rank  as  a  true  '  food '  are  at  once  apparent  from  this  statement. 

About  4I  pints  of  water  are  given  off  from  the  body  every  day  in 
the  various  excreta  and  exhalations,  and  of  this  about  one-sixth  is 
actually  formed  in  the  tissues  out  of  hydrogen  and  oxygen,  the 
remainder  being  derived  from  the  food  and  fluids  consumed.  If  one 
reckons  that  half  of  the  whole  weight  of  solid  food  taken  consists 
of  water,  then  the  amount  required  to  be  added  to  the  diet  in  an 
actually  fluid  form  would  be  approximately  2J  pints  (about  two 
breakfast-cupfuls  and  three  tumblerfuls).  Obviously,  however,  the 
exact  amount  must  vary  very  greatly  with  external  conditions,  and 
especially  with  the  amount  of  sweat  produced. 

The  nature  of  the  diet  has  also  an  important  influence  on  the 
amount  of  water  consumed.  On  this  point  some  interesting  obser- 
vations have  been  made  by  Voit,  examples  of  which  are  contained 
in  the  following  table : 

Food  consumvd.  Water  consumed.  Water  in  Faces. 

800  grammes  of  bread  . .         ..         ..  1,151  grammes.  212  grammes. 

500        ,,        of  meat  and  200  of  fat . .         760        „  25        ,, 

500        „  ,,  200  of  starch      646        „  16        „ 

1,500        „        of  meat 1,238        „  10        „ 

It  will  be  observed  that,  upon  the  whole,  the  amount  of  water 
consumed  is  proportionate  to  the  amount  contained  in  the  faeces. 
Where,  as  in  a  bread  diet,  the  fasces  are  rich  in  water,  an  increased 
amount  of  fluid  is  consumed  in  order  to  make  up  for  the  loss  from 
the  bowel.  This  fact  is  entirely  opposed  to  the  statement  not  in- 
frequently made,  that  a  diet  mainly  composed  of  vegetable  ingredients 
tends  to  lessen  thirst.  On  the  other  hand,  if  nitrogenous  food,  such 
as  meat,  is  eaten  in  large  quantities,  the  consumption  of  water  must 
also  be  increased,  owing  to  the  necessity  for  providing  for  the 
proper  elimination  of  urea  and  other  products  of  nitrogenous  waste. 


WATER  IN  THE  DIET  301 

For  this  reason  the  body  tends  to  become  richer  in  water  if  the  diet 
is  composed  chiefly  of  fats  and  carbohydrates,  and  poorer  in  water  if 
the  food  be  rich  in  protein.  We  have  already  seen  that  this  excess 
of  water  in  the  body  is  one  of  the  consequences  of  a  purely  vegetable 
diet. 

Effects  of  an  Increase  or  Diminution  of  Water  in  the 

Diet. 

If  a  litre  of  water  be  swallowed  on  an  empty  stomach,  almost  the 
whole  of  it  has  been  excreted  in  the  urine  within  the  space  of  three 
hours.  This  result  is  not  due  to  mere  dilution  of  the  blood,  for  if 
normal  salt  solution  be  taken  instead  of  water  the  result  is  precisely 
the  same.i  The  real  explanation  would  appear  to  be  that  the  total 
volume  of  the  circulating  fluid  in  the  body  is  a  fairly  fixed  quantity, 
and  is  maintained  by  some  regulating  mechanism,  so  that  it  is  not 
possible  permanently  to  increase  it.  Nor  can  the  volume  of  the  blood 
be  much  reduced  by  diminishing  the  amount  of  water  consumed.  It 
is  probable  that  such  an  effect  can  only  be  produced  for  a  very  short 
time.  Experiments  have  shown 2  that  if  the  water  of  the  diet  be 
reduced  by  about  27  per  cent,  there  is  indeed  evidence  that  the 
blood  becomes  more  concentrated,  for  in  one  such  case  the  solids  of 
the  plasma  rose  from  8-8  to  11 -6  per  cent.,  the  number  of  red  cor- 
puscles from  4,800,000  to  5,580,000  per  cubic  millimetre,  and  the 
specific  gravity  of  the  serum  from  1027-4  to  1033-4.  ^^  the  same 
time  the  arterial  tension  and  the  volume  of  the  pulse  were  diminished. 
It  was  found,  however,  that  equilibrium  was  very  readily  established, 
so  that  in  a  subsequent  experiment  the  results  were  much  less  pro- 
nounced. This  equilibrium  seems  to  be  brought  about  by  an  inter- 
change of  fluid  between  the  blood  and  the  tissues.  If  the  blood 
becomes  more  concentrated,  water  passes  into  it  out  of  the  tissues  to 
make  good  the  deficiency,  so  that  the  latter  become  drier.  Hence 
it  is  that  if  the  tissues  become  water- logged,  as  they  do  in  cardiac 
dropsy,  good  results  may  be  obtained  by  restricting  the  amount  of 
fluid  in  the  diet,  for  the  tissues  will  then  drain  themselves  into  the 
bloodvessels.  Conversely,  if  the  blood  be  habitually  overloaded 
with  water,  as  it  is  apt  to  be,  for  example,  in  those  who  habitually 
consume  large  quantities  of  beer,  some  of  the  surplus  passes  out  of 
the  vascular  area  into  the  tissues,  which  then  become  abnormally 

^  See  Falck,  Archiv  f.  Physiol.  Heilkundi    1852,  xi.  125.  and  Schmaltz,  Dcut. 
Archiv  f.  Klin.  Med.,  1891,  xlvii    145. 
»  Dennig,  Zcit.  /.  Di'dt.  md  Physik.  Therapie,  1898,  i.  281  and  ii.  292. 


3oa  FOOD  AND  DIETETICS 

watery.  The  tissues  are  therefore,  in  a  sense,  reservoirs  of  water, 
and  it  is  to  the  rapid  emptying  or  filling  of  these  that  sudden  altera- 
tions in  the  weight  of  the  body  are  usually  to  be  ascribed.  For 
example,  in  the  experiment  just  mentioned,  in  which  the  fluids  of 
the  diet  were  reduced  27  per  cent.,  the  patient  lost  8  per  cent,  of  his 
weight  within  a  week.  It  is  important  to  bear  this  influence  of 
water  on  the  body  weight  in  mind,  for  there  is  no  doubt  that  the 
fluctuations  which  it  brings  about  are  often  erroneously  attributed 
to  the  loss  or  storage  of  solids  such  as  fat.  Much  of  the  loss  of 
weight  in  acute  fevers,  for  instance,  is  certainly  due  to  increased 
dryness  of  the  body,  and  its  very  rapid  restoration  during  convales- 
cence is  the  result  of  a  retention  of  water  in  the  tissues.  The  same 
holds  good  for  obesity.  Those  who  have  insisted  upon  the  aid 
which  a  restriction  of  the  fluids  of  the  diet  furnishes  in  reducing  a 
patient's  weight  have  too  often  forgotten  that  the  reduction  is  not 
necessarily  due  to  the  removal  of  fat.  But  we  shall  return  to  this 
subject  in  discussing  the  dietetic  treatment  of  obesity. 

It  has  been  stated  that  we  are  unable,  by  increasing  or  diminishing 
the  amount  of  water  in  the  diet,  to  bring  about  any  permanent  altera- 
tion in  the  volume  of  the  blood.  It  must  not  be  concluded  from 
this  that  any  regulation  of  the  fluid  consumed  is  entirely  without 
effect  in  cases  of  disease  affecting  the  cardio-vascular  apparatus. 
Quite  the  contrary  is  the  case.  The  mere  temporary  rise  in  the 
volume  of  blood  to  be  driven  round  the  circulation  which  the  con- 
sumption of  a  large  quantity  of  fluid  brings  about,  and  the  increased 
labour  which  its  excretion  entails,  may  of  themselves  seriously 
hamper  an  already  embarrassed  heart ;  and  for  this  reason  the 
amount  of  water  in  the  diet,  in  cases  of  advanced  cardiac  disease 
and  dropsy,  may  often  be  greatly  reduced  with  nothing  but  benefit 
to  the  patient.^  On  the  other  hand,  it  must  always  be  remembered 
that,  if  the  consumption  of  fluid  be  reduced  to  the  extent  of 
increasing  the  viscosity  of  the  blood,  one  increases  thereby  the 
resistance  offered  in  the  capillary  circulation,  and  the  increased 
strain  thus  thrown  upon  the  heart  may  end  by  doing  more  harm 
than  the  restriction  of  the  volume  of  the  blood  does  good. 

One  may  perhaps  best  avoid  both  dangers  by  seeing  that  the 
amount  of  fluid  consumed  is  not  only  moderate  in  quantity,  but  is 
evenly  distributed  over  the  day,  so  that  there  is  no  period  at  which 
the  total  volume  of  the  blood  is  unduly  swelled. 

It  will  be  understood  that  very  much  the  same  remarks  apply  to 

^  A  reduction  to  30  ounces  or  less  per  day  can  usually  be  managed  without 
any  difficulty. 


WATER  AND  DIGESTION 


303 


the  treatment  of  aneurysm.  What  we  have  to  avoid  in  that  disease 
is  throwing  any  undue  strain  upon  the  weakened  vessel  walls,  and 
that  can  best  be  done  by  taking  care  that  the  circulation  is  never 
flooded  by  the  sudden  access  of  a  large  quantity  of  extraneous  fluid. 
For  a  similar  reason  it  is  often  advisable  to  restrict  the  consumption 
of  fluids  after  severe  haemorrhage,  in  spite  of  the  great  thirst  of  which 
the  patient  usually  complains,  for  the  vascular  strain  which  any 
increase  in  volume  of  the  circulating  fluid  must  inevitably  bring 
about  may  be  quite  sufiicient  to  start  the  bleeding  afresh. 

Influence  of  Water  on  Digestion. 

The  first  point  which  it  is  necessary  to  emphasize  in  this  connec- 
tion is  that  water  is  not  absorbed  by  the  mucous  membrane  of  the  stomach. 
This  is  certainly  a  surprising  fact,  but  it  has  been  incontestably 
established  both  by  physiological  experiment  and  by  observa- 
tions on  patients  suffering  from  obstruction  at  the  outlet  of  the 
stomach. 

When  water  enters  the  stomach,  it  begins  to  flow  out  into  the 
intestine  almost  at  once,  the  process  going  on  in  little  gushes 
through  the  pylorus  until  all  has  escaped.  Roughly  speaking,  one 
may  assume  that  a  pint  of  water  will  have  entirely  passed  from  the 
stomach  in  the  space  of  about  three-quarters  of  an  hour.^  The 
precise  rate  of  leaving,  however,  is  very  markedly  influenced  by 
temperature.  Hot  water  escapes  from  the  stomach  much  more 
rapidly  than  cold.'-^  The  heat  increases  powerfully  the  movements 
of  the  stomach  walls,  and  at  the  same  time  seems  to  cause  the 
pylorus  to  open,  so  favouring  the  escape  of  the  contents.  The 
stimulating  effects  which  hot  water  exerts  on  gastric  peristalsis 
render  it  a  powerful  aid  to  sluggish  digestion,  while  the  '  unlocking ' 
of  the  pylorus  which  it  brings  about  is  probably  the  explanation  of 
the  almost  instantaneous  relief  which  it  affords  in  many  cases  of 
stomach  pain. 

The  fact  that  water  is  exclusively  absorbed  in  the  intestine  has 
important  bearings  on  the  treatment  of  patients  suffering  from 
dilated  stomach.  In  the  extreme  form  of  that  disease,  when  the 
stomach  contents  are  quite  unable  to  escape  through  the  pylorus, 
the  entrance  of  water  into  the  blood  is  arrested,  and  the  patient  is 
the  victim  of  a  *  tissue  thirst,'  to  which  much  of  the  emaciation  and 
discomfort  from  which  he  suffers  must  be  attributed.  Not  only  is 
this  so.     The  deficiency  in  the  supply  of  water  to  the  blood  may  go 

*  Moritz,  Munch.  Med.  Wochensch.,  1894,  xli.  816. 

■  Schule,  Zcit.  j.  Klin.  Med.,  1895,  xxviii.  461-  «rd  1S96,  xxix.  49. 


304  FOOD  AND  DIETETICS 

so  far  that  the  proper  excretion  of  waste  products  is  interfered 
with,  and  toxic  symptoms,  such  as  coma  or  convulsions,  may  then 
supervene.  In  such  cases  there  is  an  imperious  necessity  for  getting 
water  into  the  blood  by  some  route  other  than  the  stomach,  pre- 
ferably per  rectum. 

The  rapidity  with  which  water  passes  through  the  stomach  causes 
it  to  be  a  very  dangerous  vehicle  of  infection,  for  the  hydrochloric 
acid  of  the  gastric  juice  has  no  time  to  act  upon  any  germs  which 
it  may  contain.  For  this  reason  contaminated  water  is  a  more 
obnoxious  carrier  of  disease  that  impure  milk.  All  the  greater, 
then,  is  the  reason  for  insuring  that  our  water-supply  is  above 
suspicion. 

It  is  commonly  said  that  the  free  consumption  of  water  at  meals 
is  apt  to  delay  digestion  by  diluting  the  gastric  juice.  This  state- 
ment is  not  well  grounded.  Water  is  itself  a  slight,  though 
unimportant,  excitant  of  gastric  secretion,  and  experiment  has 
shown^  that  even  in  quantities  of  \  litre  (about  a  pint)  it  does  not 
in  any  way  affect  the  rapidity  of  digestion.  Even  i  litre  produces 
only  slight  slowing,  while  it  requires  quantities  of  ij  litres  (about 
3  pints)  to  produce  any  marked  effect. 

On  the  other  hand,  it  must  be  remembered  that  water  may 
actually  hasten  the  digestion  of  some  foods  by  softening  them  and 
favouring  their  reduction  to  a  state  of  pulp,  while  hot  water  is,  as 
we  have  seen,  a  powerful  stimulant  of  the  stomach  movements. 

On  the  process  of  absorption,  water  does  not  seem  to  exercise  any 
very  marked  effect,  for  even  on  a  dry  diet  the  solid  constituents  of 
the  food  entered  the  blood  with  their  accustomed  freedom  (Dennig). 
Any  influence  which  it  may  exert,  however,  is  probably  a  favourable 
one. 

Influence  of  Water  on  Metabolism. 

The  influence  of  water  on  the  chemical  processes  of  the  body 
would  seem  to  be  very  slight.  It  was  formerly  believed  that  an 
increased  consumption  of  water  was  accompanied  by  an  increased 
waste  of  the  nitrogenous  tissues.  This  is  now  regarded  as  an  error. 
Any  increased  excretion  of  nitrogen  which  a  free  consumption  of 
water  entails  is  now  ascribed,  not  to  an  increased  breaking-down  of 
the  body  substance,  but  to  a  washing-out  of  the  tissues  and  the 
elimination  of  waste  matters  loitering  in  them.''  This  eliminative 
hinction  of  water  is  one  of  the  first  importance.     It  indicates  the 

*  Fleischer,  Berliner  Klin.  Wochensch.,  1882,  xix.  97. 

*  See  K.  O.  Neumann,  Archiv.f.  Hygiene,  1899,  xxxvi.  248. 


VARIETIES  OF  WATER  305 

necessity  for  a  free  supply  of  that  fluid  in  such  diseases  as  gout, 
diabetes,  and  fevers,  and  in  cases  in  which  the  excretory  power  cf 
the  kidney  is  deteriorated. 

Varieties  of  Water. 

A  good  drinking  water  should  have  little  or  no  colour,  no  odour, 
a  pleasant,  fresh  taste,  and  should  contain  only  a  moderate  amount 
of  solid  matter,  8^  grains  per  gallon  being  a  good  average.  A 
tumblerful  of  ordinary  London  water  contains  only  about  one 
grain  of  solids.  A  wholesome  water  should  contain  very  little 
organic  matter,  and  that  should  be  of  vegetable  origin,  and  if  it 
has  anything  like  a  large  proportion  of  chlorides  it  should  be  viewed 
with  suspicion. 

The  amount  of  lime  salts  which  drinking  water  contains  is  a 
matter  of  some  importance,  and  the  relative  merits  of  hard  and 
soft  water  for  drinking  purposes  have  been  much  discussed.  It  has 
been  maintained  on  the  one  hand  that  hard  waters  are  apt  to  be 
productive  in  those  who  habitually  consume  them  of  such  diseases 
as  goitre  and  stone,  while  on  the  other  hand  it  has  been  said  that 
soft  waters  may  favour  the  development  of  rickets.  It  must  be 
admitted  that  neither  of  these  contentions  is  very  well  founded, 
but  it  may  be  granted  that  it  is  well  that  the  water  one  drinks 
should  not  contain  more  than  15  grains  of  lime  salts  in  every 
gallon,  and  that  the  sulphate  of  lime  is  more  likely  to  be  harmful 
than  the  carbonate,  for  in  some  susceptible  persons  its  presence 
may  excite  dyspepsia  and  diarrhoea. 

The  fear  that  the  use  of  soft  water  may  lead  to  the  development 
of  rickets  is  quite  groundless.  When  one  remembers  that  even  a 
hard  water  only  contains  about  0'002  grm.  of  lime  in  every  100  c.c, 
and  that  an  infant  requires  about  0-32  grm.  of  lime  daily,  it  will  be 
evident  that  as  a  source  of  calcium  for  the  bones  water  may  be 
practically  disregarded.  On  the  other  hand,  there  is  no  doubt  that 
soft  waters  are  more  liable  to  become  contaminated  with  lead  than 
those  which  are  richer  in  lime  salts,  and  in  that  respect  at  least  soft 
water  may  be  a  source  of  danger  to  health. 

The  dangers  of  water  as  a  source  of  infection,  owing  to  its  con- 
tamination with  the  germs  of  disease,  have  already  been  mentioned, 
and  one  of  the  reasons  for  it  pointed  out.  The  avoidance  of  such 
contamination,  and  the  provision  of  pure  water  on  a  large  scale,  is 
one  of  the  most  important  duties  of  the  Public  Health  Authorities 
in  any  community,  but  the  methods  by  which  these  results  are  to 

be  obtained  hardly  fall  within   the   scope   of  this   work.      One  is 

ao 


3o6  FOOD  AND  DIETETICS 

frequently,  however,  asked  for  advice  as  to  the  domestic  purification 
of  water,  and  as  to  the  best  means  of  avoiding  the  risk  of  infection 
from  it,  especially  during  epidemics.  The  reply  one  should  make 
to  such  inquiries  is  quite  clear.  The  07ily  sure  method  of  render- 
ing water  harmless  is  by  boiling  it.^  It  may  be  objected  that 
this  gives  the  water  a  flat  and  insipid  taste,  but  that  objection  can 
easily  be  overcome  by  subsequent  aeration  in  a  gazogene,  or  by 
simply  shaking  up  the  water  with  air  in  a  stoppered  bottle.  The 
invention  known  by  the  name  of  the  Sparklets  Process  is  also  a 
very  simple  and  efficient  method  of  aerating  water,  and  so  over- 
coming the  flatness  produced  by  boiling.  For  convenience  in  out- 
of-door  use  and  when  travelling  it  surpasses  all  other  methods.  The 
addition  of  toast,  also,  to  boiled  water  communicates  to  the  latter 
the  flavour  of  some  of  the  soluble  ingredients  of  the  toast,  and  has 
long  been  in  use  as  a  means  of  overcoming  the  flatness  produced  by 
boiling. 

Before  leaving  this  subject,  one  must  also  warn  the  reader  against 
the  delusion  so  ofu.i  cherished,  that  the  addition  of  a  little  wine,  or 
even  spirits,  to  water  can  kill  any  germs  that  are  in  it,  and  so  render 
it  safe.  That  is  not  the  case;  the  proportion  of  alcohol  in  the 
mixture  is  never  high  enough  to  be  certain  of  killing  the  organisms. 


Aerated  and  Mineral  Waters. 

Artificial  aerated  waters,  which  are  now  so  familiar,*  were  invented 
by  the  distinguished  chemist  Joseph  Priestley  in  the  latter  half  of  the 
eighteenth  century .^  They  are  made  by  charging  water  with  carbonic 
acid  gas  at  high  pressure,  the  gas  being  derived  from  the  action  of 
vitriol  on  chalk.  Ordinary  bottles  of  aerated  water  contain  3  or  4 
volumes  of  carbonic  acid  gas  to  i  volume  of  water ;  syphons  contain 
more.  There  is  no  doubt  that  this  proportion  is  needlessly  high,  and  has 
the  effect  of  causing  such  violent  ebullition  when  the  bottle  is  opened 
that  some  of  the  contents  are  apt  to  be  lost  during  the  escape  of  the 
surplus  gas.     The  only  advantage  attendant  upon   this  process  is 

1  The  Berkefeld  and  Pasteur  filters,  if  used  with  intelligence  and  care,  may 
also  be  depended  upon  to  render  water  free  from  disease  germs. 

2  It  has  been  calculated  that  upwards  of  200,000,000  gallons  of  aerated  waters 
are  consumed  in  the  United  Kingdom  per  annum. 

'  '  Directions  for  Impregnating  Water  with  Fixed  Air,  in  order  to  Communi- 
cate to  it  the  Peculiar  Spirit  and  Virtues  of  Pyrmont  Water  and  other  Mineral 
Waters  of  a  Similar  Nature,'  Joseph  Priestley,  London,  lya.  For  a  full  account 
of  the  histor}'  of  the  subject  see  '  The  Evolution  of  Natm  il  Mineral  Waters,'  by 
William  Kirkby  (Manchester:  Jewsbuiyand  Brown.  1902). 


AERATED  AND  MINERAL   WATERS  307 

that  the  gas,  as  it  passes  off,  withdraws  from  the  water  a  consider- 
able amount  of  heat,  so  that  aerated  waters  are  always  cooler  to  the 
taste  than  ordinary  water  kept  under  the  same  conditions. 

The  varieties  of  artificial  aerated  waters  which  call  for  mention 
are  as  follows : 

1.  Ordinary  Water  impregnated  with  Carbonic  Acid  Gas. — The  best 
makers  obtain  the  water  from  artesian  wells,  so  that  it  is  of  great 
purity.  Ordinary  water  so  impregnated  is  often,  but  erroneously, 
described  as  'soda-water.'  As  soda  is  sometimes  entirely  absent,  it 
is  better  to  describe  it  simply  as  '  carbonated  water.' 

2.  Aerated  Distilled  Water. — In  this  case  the  water  is  distilled  prior 
to  being  charged  with  gas.  It  is  therefore  entirely  free  from  mineral 
matter  and  from  all  impurities.  Examples  of  such  water  are  sold 
under  the  names  of  '  Puralis,'  '  Salutaris,'  and  *  Globenaris.'^ 

3.  Water  to  which  Various  Che. leal  Salts  have  been  added,  e.g.  : 

Soda  water,  containing  3  to  5  grains  of  bicarbonate  of  soda  to  the  bottle. 
Medicinal  soda  water,  containing  15  grains  of  bicarbonate  of  soda  ditto. 
Potash  water,  containing  15  grains  of  bicarbonate  of  potash  ditto. 
Magnesia  water,  containing  is  grains  of  carbonate  of  magnesia  ditto. 
Carrara  water,  containing  5  grains  of  lime  ditto. 
Lithia  water,  containing  3  to  5  grains  of  carbonate  of  lithia  ditto. 

4.  Imitations  of  Various  Natural  Mineral  Waters. — One  of  the  best 
examples  of  these  is  seltzer-water,  which  is  intended  to  be  a  sub- 
stitute for  the  natural  water  obtained  from  the  Selters  spring.  Its 
ingredients  are  common  salt,  bicarbonate  of  soda,  carbonate  of  mag- 
nesia, and  hydrochloric  acid.  By  the  interaction  of  these  constituents 
an  aerated  water  is  produced  which  '  gives  a  good  imitation  of  the 
peculiar  mellowness  of  genuine  seltzer.'  An  analysis  of  Schweppe's 
seltzer  showed  it  to  contain  1*13  grains  of  mineral  matter  per 
imperial  pint,  or  0*620  grain  per  bottle.  A  tumblerful  had  an 
acid-neutraliiing  power  equal  to  that  of  37^  c.c.  of  decinormal  soda 
solution. 

5.  Sweetened  and  Flavoured  Mineral  Waters. — This  is  the  large  and 
popular  group  which  includes  lemonade,  ginger-beer,  et  hoc  genus 
ovine.  The  basis  of  their  composition  is  water  sweetened  with  cane- 
sugar,  and  rendered  tart  by  the  addition  of  an  acid,  then  flavoured  in 
any  way  desired,  and  finally  charged  with  carbonic  acid  gas. 

A  bottle  of  such  water  contains  about  i  ounce  of  sugar  (equal  to 
five  or  six  ordinary  lumps).  Unless  the  water  is  sold  as  a  genuine 
•  fruit  product '  the  acid  added  is  only  exceptionally  citric  or  tar- 
taric; far  more  often  one  finds  that  a  mineral  acid  is  used,  most 

1  An  excellent  aerated  distilled  water  is  also  prepared  by  Packham  and  Co., 
Ltd.  (Croydon). 


3o8  FOOD  AND  DIETETICS 

commonly  phosphoric,  in  the  form  of  so-called  '  phospho-lactic '  or 
*  phospho-citric  '  acid.  Some  makers  employ  acetic  acid.  If  citric 
or  tartaric  acid  is  used,  the  amount  added  is  about  lo  grains  per 
bottle,  and,  as  a  rule,  the  acidity  of  a  bottle  of  ordinary  mineral 
water  of  this  class  may  be  reckoned  as  about  equal  to  that  of  a 
tablespoonful  of  good  vinegar. 

The  following  recipes  for  making  mineral  waters  are  taken  from 
the  '  Mineral  Water  Maker's  Manual '  (1896),  and  will  serve  to  show 
the  constituents  of  some  of  these  products : 

Lemonade.  Orangeade. 

Plain  syrup, »  i  gallon.  Plain  syrup,  i  gallon. 

Lemon  tincture,  4  ounces.  Orange  tincture.  4  to  6  ounces. 

Acetic  acid,  4  to  5  ounces.  Acetic  acid,  4  ounces. 

I  to  li  ounces  to  the  bottle.  i  to  ij  ounces  to  the  bottle. 

Ginger-beer.  Gingerade. 

Plain  syrup,  3  quarts.  Plain  syrup,  i  gallon. 

^           Boiling  water,  i  quart.  Tincture  of  ginger,  4  ounces. 

Oil  of  lemons,  24  minims.  Acetic  acid,  4  ounces. 

Acetic  acid,  4  fluid  ounces.  Bitter  orange  tincture,  q.s. 

Tincture  of  ginger,  q.s.  i  to  i^  ounces  to  the  bottle. 
I  to  i^  ounces  to  the  bottle. 

Ginger-ale. 
Plain  syrup,  i  gallon. 
Compound  tincture  of  ginger,  4  ounces. 
(Or  tincture  of  capsicum,  i  ounce.) 
Acetic  acid,  4  ounces. 
Sugar  colouring,  ^  ounce. 
I  to  ij  ounces  to  the  bottle. 

It  will  be  observed  that  ♦  lemonade  '  and  '  orangeade  '  have  very 
little  to  do  with  the  fruits  from  which  they  derive  their  names.  The 
term  '  ginger-beer  '  or  '  ginger-ale  '  is  even  more  ambiguous.  The 
article  so  named  may  have  nothing  to  do  with  ginger  at  all,  for  the 
requisite  degree  of  sharpness  is  usually  obtained  by  aid  of  tincture  of 
capsicum. 

Genuine  fermented  ginger-beer  ('  stone  ginger ')  is  a  very  different 
product.     The  following  are  its  ingredients  : 

Water 21  gallons. 

Sugar 21  pounds. 

Bruised  gin'.;er  ..         ..  i\  pounds. 

Tartaric  acid 6  ounces. 

Gum  arable    ..         ••         ..  i  pound. 

Oil  of  lemon Jounce. 

Yeast i  pint. 

.\s  the  result  of  fermentation  it  usually  contains  at  least  2  per  cent, 
of  alcohol,  sometimes  considerably  more. 

^  10  pounds  of  sugar  to  x^  gallons  of  water. 


NATURAL  MINERAL   WATERS 


309 


Natural  Mineral  Waters. 

These  are  obtained  from  natural  springs,  and  the  majority  of 
them  are  impregnated  with  carbonic  acid  gas.  The  mineral 
matters  which  they  contain  are  very  various,  but  the  most 
abundant  are  common  salt  and  alkaline  salts  of  soda  or  lime. 
For  ordinary  table  use  a  water  must  not  contain  more  than  i  per 
cent,  of  mineral  matter,  for  above  that  one  begins  to  get  the 
specific  effect  of  its  salts. 

The  following  table  contains  a  description  of  the  natural  table 
waters  most  largely  used  in  this  country,  and  the  results 
which  were  obtained  from  a  comparison  of  their  respective  acid- 
neutralizing  powers : 


Apollinaris' 


Rosbach 


Jofaannis 


Mineral 

Matter 

in  an 

Imperial 
Pint  (in 
Grms.). 


Perrier 


2 '27 


1-05 


1-58 


Mineral 

Matter 

in  a 

Bottle  (in 
Grms. ). 


I  "40 


0'6i 


0-95 


Acid-neutralizing 
Power  of  250  c.c. 
(=1  tumblerful), 
expressed  in  c.c. 
of  Decinormal 
Caustic  Soda. 


91-8  C.C. 
^NaOH 


293  c.c. 


31  8  c.c. 


15  o  c.c. 


General  Description  and  Remarks. 


From  spring  in  valley  of  Ahr 
(Rhenish  Prussia).  An  alkaline, 
highly  aerated,  and  slightly  chlor- 
inated water.  Chief  constituents : 
sodium  chloride  and  carbonates  of 
soda,  lime,  and  magnesia. 

From  spring  near  Homburg.  Mildly 
alkaline ;  well  aerated ;  lightly 
mineralized  ;  containing  about 
12  grammes  of  sodium  chloride 
and  05  grammes  of  earthy  car- 
bonates in  a  litre. 

Produced  at  Johannis  springs  (Zoll- 
haus  in  Nassau).  Mildly  alkaline 
and  well  aerated.  Chief  salts  are 
carbonates  of  lime,  soda,  and  a 
small  amount  of  sodium  chloride. 
A  lithiated  Johannis  is  made  from 
this,  containing  i  grain  of  bicar- 
bonate of  lithia  per  bottle, 

A  lightly  mineralized  and  well- 
aerated  natural  water.  The  chief 
salt  present  is  bicarbonate  of  soda. 
Obtained  from  springs  at  Les 
Bouillens,  Vergeze,  in  France. 


1  For  a  fuller  description  of  this  water  see  the  Lancet  {'  Some  Points  concern- 
ing Natural  Mineral  Waters  in  General  and  Apollinaris  Water  in  Particular '), 
January  30,  1904. 


iio  FOOD  AND  DIETETICS 

Others  are : 

Vichy  (Etat),  with  8  grammes  solids  per  litre  (5  grammes  bicarbonate  of  soda). 

It  has  a  high  acid-neutraHzing  power,  250  cc.  =  26S  c.c.  decinormal  acid, 

but  cannot  be  regarded  as  a  water  adapted  for  use  in  health. 
St.  Galmier,  which  is  largely  used  in  France,  has  2 '8  grammes  solids  per  litre, 

chiefly  earthy  bicarbonates. 
Contrexeville  (Pavilion)  has  2*3  grammes  solids  of  a  similar  nature,  and  is  only 

slightly  gaseous. 
Sparkling  Malvern  is  a  pure  natural  water  derived  from  the  Malvern  springs. 

It  has  18  grammes  of  solids  per  litre  (o '866  gramme  per  bottle),  including 

I  gramme  of  sodium  carbonate  and  075  gramme  of  sodium  chloride. 
Seltzer  (Nieder-Selters,  in  Nassau)  has  36  grammes  solids  per  litre,  consisting 

of  224  of  sodium  chloride  and  1*3  of  carbonates. 
Adonis  is  a  mildly  alkaline  water,  containing  2*3  grammes  sodium  bicarbonate 

per  litre.     It  is  soft  and  well  aerated,  and  is  derived  from  springs  situated  in 

the  Belgian  Ardennes. 
Sinaro  is  a  natural  sparkling  water  derived  from  springs  near  Wiesbaden, 

Nassau.     Its  chief  mineral  ingredients  are  the  bicarbonates  of  calcium  and 

sodium. 

Uses  of  Mineral  Waters. 

What  dietetic  advantages  are  obtained  from  the  iinpregnation  of 
water  with  carbonic  acid  gas  ?  Apart  from  the  pleasant,  sharp 
taste  which  such  water  possesses,  one  finds  that  carbonic  acid  gas  is 
an  undoubted  aid  to  digestion.  Indeed,  it  may  be  said  that  the 
mineral  waters  stand  alone  among  beverages,  in  that  they  actually 
promote  the  chemical  processes  of  digestion  by  causing  an  earlier  and 
more  abundant  secretion  of  gastric  juice.^  Not  only  is  this  the 
case ;  carbonic  acid  acts  as  a  stimulant  to  the  movements  of  the 
stomach,  and  so  aids  the  mechanical  processes  of  digestion  also, 
while  the  bubbling  up  of  the  gas  through  the  stomach  contents 
doubtless  facilitates  their  disintegration. 

There  are  cases,  however,  in  which  such  waters  should  be  avoided. 
Carbonic  acid  gas  is  rapidly  absorbed  from  the  stomach  into  the 
blood,  and  where  that  fluid  already  contains  an  excess  of  the  gas,  as 
it  does  in  cyanosis,  it  may  be  well  not  to  run  the  risk  of  adding  to  it. 
The  mechanical  distension  of  the  stomach,  too,  which  the  escape  of 
the  gas  induces,  may  be  harmful  in  dilatation  of  that  organ,  and  in 
other  cases  may  hamper  a  weakened  heart  by  causing  the  fundus  of 
Ihe  stomach  to  press  up  against  it.  The  use  of  mineral  waters 
should  also  be  avoided  in  cases  in  which  the  appetite  is  much 
depressed,  for  the  carbonic  acid  gas,  by  lowering  the  sensibility  of  the 
Btomach  nerves,  may  still  further  impair  the  desire  for  food. 

Unfortunately,  it  cannot  be  justly  claimed  for  the  aerated  waters 
that    they    are  always  sterile.     Carbonic  acid   gas  is   ftot    fatal   to 

^  Penzoldt,  '  Die  Wirkung  der  Kohlensaure  auf  die  Magenverdauung, '  Deut 
Archiv.  f.  Klin.  Med.,  1902,  Ixxiii.  200. 


USES  OF  MINERAL   WATERS  311 

organisms,  with  the  exception,  perhaps,  of  the  cholera  bacillus.  On 
the  other  hand,  the  mineral  waters  supplied  by  the  best  makers  are 
usually  prepared  from  water  obtained  from  artesian  wells,  and  on 
that  account  are  likely  to  be  free  from  the  germs  of  disease.  The 
distilled  aerated  waters  are  also  beyond  reproach  in  this  respect,  but 
they  should  not  be  taken  in  large  quantities  unless  along  with  food, 
for  there  is  reason  to  believe  that  distilled  water  may  have  injurious 
local  effects  in  the  stomach,  and  lead  to  nausea  and  vomiting  by 
destroying  its  surface  epithelium. 

The  question  of  natural  versus  artificial  mineral  waters  must  be 
decided  entirely  in  favour  of  the  former.  For  one  thing,  the  natural 
waters  do  not  contain  any  excess  of  gas,  and  a  larger  proportion  of 
what  they  do  contain  is  present  in  a  combined  form  than  is  the  case 
with  the  artificial  waters.  Hence  their  gas  is  given  off  more  slowly, 
and  they  remain  longer  brisk,  and  are  less  apt  to  lead  to  sudden  dis- 
tension of  the  stomach.     The  following  experiment  bears  this  out^ : 

Natural  Artificial 

Water.  Water. 

Gas  evolved       ..         480  c.c.  760  c.c.  )  Bottle  opened  and  exposed 

Gas  remaining  . .      1,010  c.c.  723  c.c.  j  for  half  an  hour. 

Total         ..      1,490  c.c.  1,4830.0. 

There  is  also  reason  to  believe  that  the  effects  of  the  salts  in 
natural  mineral  waters  are  such  as  cannot  be  obtained  from  any 
artificial  imitation  of  them.  The  reasons  for  this  have  been  discussed 
by  Koeppe.2  He  attributes  it  to  the  fact  that  the  natural  waters 
contain  traces  of  many  salts  which  are  not  present  at  all  in  the 
artificial  waters,  and  which  are  yet  not  without  effect  on  the  body. 
Being  formed  under  pressure,  too,  the  natural  waters  contain  double 
salts,  the  physical  effects  of  which  are  not  comparable  to  each  salt  taken 
separately,  for  each  salt  has  its  own  partial  pressure,  while  for  any 
given  degree  of  concentration  one  finds  fewer  dissociated  '  ions.'  This 
is  not  without  influence  on  the  physical  processes  of  osmosis,  and  as 
a  matter  of  fact  it  has  been  found  that  more  mineral  matter  is 
absorbed  in  a  given  time  by  the  intestine  of  a  dog  from  a  natural 
than  from  an  artificial  water. 

The  slight  alkalinity  of  some  of  these  waters  renders  them  useful 
additions  to  the  more  acid  wines,  for  the  inhibitory  action  of  the 
latter  on  the  saliva  is  thereby  corrected. 

The  sweetened  mineral  waters,  such  as  lemonade,  are  apt  to  dis- 

*  Analytical  Reports,  Lancet,  August  S,  1891. 

■  See  footnote,  p.  285,  and  Dr.  Brasch,  Zeit.  f.  Didt.  und  Pkysift.  Therapie, 
1900,  ill.  683. 


312  FOOD  AND  DIETETICS 

agree  with  the  stomach  and  produce  '  acidity,'  both  by  reason  of  the 
acid  which  they  contain,  and  also  from  the  action  of  their  sugar  on 
the  secretory  processes  in  the  stomach,  and  perhaps  also  by  fermenta- 
tion. On  the  other  hand,  it  must  be  remembered  that  such  beverages 
are  by  no  means  devoid  of  nutritive  value,  for  a  bottle  of  one  of  them 
contains  enough  sugar  to  yield  nearly  115  Calories  of  energy  to  the 
body  ;  and  their  refreshing  influence  in  fatigue  may  also  be  explained 
by  reference  to  the  value  of  sugar  as  a  food  in  exhaustion  (see  p.  282) 


[  313  1 


CHAPTER  XVIII 

TEA,  COFFEE,  AND  COCOA 

In  dealing  with  these  beverages,  it  will  be  convenient  to  take  up  the 
history,  mode  of  manufacture,  and  chemistry  of  each  of  them 
separately,  and  then  to  consider  their  action  on  digestion  and  their 
uses  in  the  diet  together. 

Tea.» 

1.  History. — Tea  was  introduced  into  Europe  by  the  Dutch  East 
India  Company  in  the  year  i6io.  As  its  price  was  at  first  ten 
guineas  a  pound,  it  can  be  readily  imagined  that  it  grew  but  slowly 
in  popularity,  and  even  in  i66o  we  find  Pepys  writing  in  his  Diary: 
'  I  sent  for  a  cup  of  tee,  a  China  drink,  of  which  I  had  never  drank 
before.'  By  the  beginning  of  the  last  century  the  annual  consump- 
tion had  risen  to  i^  pounds  per  head  of  the  population,  and  now  it 
amounts  to  about  6*6  pounds  per  head.  In  Great  Britain,  indeed, 
we  consume  more  than  all  the  European  countries  put  together,  about 
800,000  pounds  of  tea,  or  5,000,000  gallons  of  the  beverage,  being 
used  daily.  It  is  only  in  Australia,  where  tea  is  so  largely  used  in  the 
Bush,  that  the  consumption  surpasses  that  of  this  country,  amounting 
as  it  does  to  9  pounds  per  head  of  the  population  annually. 

Up  to  the  year  1862  nearly  all  our  tea  was  obtained  from  China, 
the  imports  from  that  country  reaching  their  maximum  in  1879. 
Since  that  time  the  consumption  of  China  teas  has  rapidly  declined, 
their  place  being  taken  by  Indian  tea,  and,  since  1880,  by  teas  grown 
in  Ceylon.  The  proportion  of  China  tea  is  now  less  than  12  per 
cent,  of  the  total  import. 

2.  Mode  of  Manufachire. — Tea  was  originally  obtained  from  the 
leaves  of  the  Thea  chtJiensis  and  Thea  assamica,  both  of  the  Camellia 

1  I  am  indebted  for  much  valuable  information  on  the  subject  of  tea  to  the 
following,  among  other  publications:  Bannister's  Cantor  Lectures,  1895;  A.  G. 
Stantor,  journal  of  the  SocUty  of  Arts,  January  25,  1890  ;  Prescott,  Popular  Science 
Monthly,  u.  359,  1882. 


314 


FOOD  AND  DIETETICS 


order;  but  many  hybrids  are  now  used  for  tea  production.  The 
plant  '  flushes,'  or  sends  out  young  shoots,  four  times  in  the  year, 
and  is  '  picked '  at  each  '  flush.'  In  China  and  Japan  the  best  tea  is 
obtained  from  the  first  'flushing,'  but  in  India  and  Ceylon  this  is 
not  the  case. 

The  varieties  of  tea  are  named  according  to  the  different  leaves 
from  which  they  are  produced 
(Fig,  28).  The  young  shoot  has 
two  small  leaves  at  its  tip  which 
contain  least  fibre  and  most  juice, 
and  therefore  produce  the  finest 
sort  of  tea.  In  India  and  Ceylon, 
tea  produced  from  these  leaves  is 
called  '  flowery  *  and  '  orange  ' 
'  Pekoe,'  or,  if  the  leaves  are  still 
smaller,  'broken  Pekoe.'  The 
tea  produced  from  a  somewhat 
larger  leaf  just  below  this  is  called 
'  Pekoe ';  the  next  largest  leaves 
produce  *  Souchong ';  the  leaves 
below  that,  '  Congou  *  (though 
these  are  not  often  picked  now) ; 
while  a  still  coarser  leaf  near  the 
base  of  the  shoot  used  to  yield 
'  Bohea,*  which  has  now, 
ever,  almost  disappeared 
commerce.^ 

In  China  a  slightly  different 
nomenclature  is  used,  the  whole  end  of  the  young  shoot,  with  its 
cluster  of  leaves,  going  to  form  '  Pekoe,'  while  the  leaves  below  that 
are  used  for  the  production  of  *  Souchong.' 

It  should  be  noted  also  that  the  term  '  Congou '  is  often  applied  in 
the  retail  trade  to  blends,  while  *  Pekoes '  and  '  Souchongs '  are 
unblended  teas. 

The  treatment  of  the  leaves  after  they  are  picked  varies  according 
as  black  or  green  tea  is  to  be  produced. 

For  the  production  of  black  tea,  the  leaves  are  *  withered,'  then 
rolled  till  they  become  soft  and  '  mashy,'  the  object  of  this  being 

1  'Pekoe'  is  deri%ed  from  'poco,'  the  hair  or  down  on  the  young  buds; 
'  Souchong  '  means  '  little  sprouts  ';  and  '  Congou  '  signifies  labour,  from  the  care 
required  in  the  subsequent  treatment  of  the  leaves.  It  should  be  noted  that  to  a 
large  extent  the  varieties  or  grades  of  tea  described  above  have  now  become 
mere  commercial  terms,  witb  little  relation  to  any  particular  leaves. 


Fig.  28. — Young  Shoot  of  Tea 
Plant  (after  Money). 

L  a,    Flowery   Pekoe  ;    b,  Orange  Pekoe ; 

tiow-  ^  Pekoe  ;  d.  Souchong  (first) ;  e.  Sou- 
from       chong  (second) ;  /,  Congou  ;  H.  Bohea ; 

a  and  b  (mixed),  Pekoe ;  a,  b,  c,  d,  and 

e,  Pekoe-Souchong. 


VARIETIES  OF  TEA  315 

to  break  up  the  fibre  and  cells  of  the  leaf,  and  liberate  the  con- 
stituents, so  that  they  are  afterwards  more  easily  extracted,  and 
then  allowed  to  ferment.  During  the  process  of  fermentation,  some 
of  the  tannic  acid  in  the  leaves  appears  to  be  oxidized  and  converted 
into  less  soluble  forms,  while  more  essential  oils  seem  to  be  pro- 
duced, and  a  certain  amount  of  bitterness  developed.  After 
fermentation  is  complete  the  leaves  are  '  fired '  in  a  drying- 
machine. 

For  the  production  of  green  tea,  the  fresh  leaves  are  withered  in 
hot  pans  at  a  temperature  of  160°  F.  (Chinese  method),  or  steamed 
(Japanese  method) ;  then  rolled  to  break  them  up  and  liberate  their 
juices  ;  then  '  fired.' 

It  will  be  observed  that  the  chief  difference  between  black  and 
green  tea  is  that  the  former  is  fermented,  while  the  latter  is  not ;  and 
one  of  the  main  results  of  fermentation  seems  to  be  to  render  the 
tannic  acid  less  soluble,  so  that,  as  we  shall  shortly  see,  an  infusion 
of  green  tea  contains  more  tannin  than  an  infusion  of  black. 

In  former  days  a  good  deal  of  so-called  green  tea  was  really  made 
in  the  same  way  as  black,  and  subsequently  '  faced '  with  Prussian 
blue  or  indigo  to  give  it  the  proper  colour ;  but  I  am  informed  that 
this  does  not  take  place  now  to  any  important  extent. 

We  have  seen  that  the  quality  of  teas  varies  with  the  age  of  the 
leaf  from  which  they  are  prepared,  the  younger  leaves  yielding  the 
finest  tea.  Apart  from  this  cause  of  variation,  teas  show  marked 
differences  according  to  the  country  and  district  in  which  they  are 
produced. 

Chinese  teas  have  the  most  delicate  flavour  of  any,  but  are 
rather  lacking  in  '  body ';  they  are  also  devoid  of  any  marked 
astringency. 

Indian  teas,  and  especially  those  produced  in  Assam,  have  the 
greatest  degree  of  *  body  *  and  astringency.  This  makes  them 
powerful  teas,  suited  rather  for  blending  with  milder  varieties  than 
for  drinking  alone. 

Ceylon  teas  have  plenty  of  body,  and  a  rich  and  peculiar  flavour, 
but  have  not  so  much  strength  or  pungency  as  the  Indian  varieties. 

According  to  the  district  in  which  they  are  produced,  Chinese 
black  teas  may  be  divided  into  : 

1.  Monings,  from  North  China,  with  a  small  and  delicate  leaf  and 
a  peculiar  malty  flavour. 

2.  Kaisows,  from  South  China,  the  so-called  red-leaf  teas,  because 
the  original  teas  grown  in  this  district  had  a  reddish  leaf. 


3i6  FOOD  AND  DIETETICS 

3.  Oolongs,  from  Formosa,  pungent  and  slightly  bitter,  yielding 
a  pale  infusion,  and  chiefly  used  for  purposes  of  blending. 

4.  Scented  orange  Pekoe  and  scented  Caper  come  from  the  Canton 
district,  and  yield  a  pale,  strong  infusion  with  an  aromatic  flavour, 
for  which  reason  they  are  used  to  give  bouquet  to  blends.  Caper 
is  really  an  unfermented  tea,  highly  fired,  and  standing  intermediate 
between  the  black  and  green  varieties. 

Of  Indian  black  teas  those  from  the  Darjeeling  district  are  best, 
being  less  rough  and  astringent  than  those  from  Assam,  and  well 
adapted  for  drinking  alone.  It  should  be  remembered  that  most  black 
teas  in  the  market  are  really  blends  of  Indian,  Ceylon  and  China  in 
different  proportions. 

Most  green  teas  come  from  North  China  and  Japan,  the  latter 
yielding  the  best.     Very  little  is  produced  in  India. 

The  chief  varieties  of  green  tea  are  Young  Hyson^  and  Gunpowder, 
the  former  corresponding  to  a  Souchong  among  black  teas,  and  the 
latter  to  Congou. 

In  judging  a  tea,  professional  tea-tasters  are  guided  by  the  nature 
of  the  liquor  and  the  characters  of  the  infused  leaves  or  '  out-turn.' 

The  infusion  should  be  of  a  reddish-golden  colour,  pungent  in 
flavour,  but  not  too  bitter  or  astringent,  and  not  '  thin '  or  '  hard.' 

The  infused  leaves  should  be  of  a  bright  coppery  tint,  and  evenly 
extracted,  so  that  some  do  not  look  darker  than  others  ;  they  should 
be  uniform  in  size,  and  after  five  minutes'  infusion  should  not  be 
completely  unrolled.  There  should  not  be  too  much  stalk  mixed 
with  the  leaves. 

3.  Chemical  Composition  of  Tea. — The  following  analyses  of  two 
typical  varieties  of  tea  are  given  by  Bannister  :' 

Congou,  at  Young  Hyson, 

25.  lod.  at  3s. 

(Typical  (a  Typical 

Black  Tta).  Green  Tea). 

Water           820  596 

Caffeine        324  2-33 

Albumin  (insoluble)           ..         ..     1720  16-83 

,,         (soluble) 070  o-8o 

Alcoholic  extract    ..         ..         ..       679  yos 

Dextrin         . .         . .         . .         . .        —  0*50 

Pectin  and  pectic  acid      ..         ..2-60  3*22 

Tannic  acid . .         ..         ..         ..     1640  2714 

Chlorophyll  and  resin       ..         ..       4'6o  4-20 

Cellulose 34°  25"90 

Ash 627  607 

*  Young  Hyson  =  Yu-Chien,  '  before  the  rains.' 

*  Cantor  Lectures,  1890. 


COMPOSITION  OF  TEA  317 

Of  these  ingredients,  the  most  important  are  the  alkaloid  caffeine 
(also  called  theine)  and  tannic  acid ;  for  these,  along  with  a  small 
proportion  of  volatile  oil  (^  per  cent.),  are  the  ingredients  to  which 
the  chief  effects  of  tea  on  the  body  are  due.  The  importance  of  the 
caffeine  and  tannic  acid  is  so  great  that  it  may  be  well  to  bring 
fo  ward  some  further  and  very  exact  estimations  of  these  ingredients 
in  different  teas  which  were  made  by  Allen  :^ 

Description  of  Tea .  Tannic  Acid.  Caffeine. 

Ceylon,  whole  leaf  (Pekoe)  ,,  ..  1301  per  cent.  385  per  cent. 

,,         broken  leaf        ..  ..  ..  12-31         ,,  403 

Assam,  whole  Iccif  (Pekoe)  ..  ..  1008        „  402 

,,        broken  leaf        ..  ..  ..  11  33        „  402 

Java  Pekoe  ..         ..  ..  ..  1293        „  375 

Kaisow,  red  leaf . .         ..  .,  ..  1135        „  341 

Moning,  black  leaf         ..  ,.  ..  1176        „  374 

Moyune  Gunpowder      ..  ..  ..  1295         „  289 

Natal  Pekoe  Souchong  . .  ..  ..  990        „  308 

Indian  and  Ceylon  teas  are  richer  in  all  the  chief  ingredients 
(caffeine,  tannic  acid,  and  volatile  oil)  than  China  teas.  Green  tea 
is  richer  in  tannic  acid  than  black,  but  the  amount  of  caffeine  in  the 
two  is  almost  the  same.  The  following  table^  (from  analyses  by 
Mr.  Y.  Kozai  in  Japan)  shows  the  difference  in  composition  between 
green  and  black  tea  produced  from  the  same  leaves  : 

Original 

Leaves.^ 

Per  cent. 
Crude  protein    ,,         ,,         ,,         ..3735 
fibre         ..         .,  ,.         ,.     iO'44 

Ethereal  extract  ..         ..         ..       649 

Other  nitrogen-free  extract     ..         ..     2786 

Ash  ..  ..  ..  ,,  ..       4'97 

Caffeine  ..         330 

Tannic  acid*       ..  .,         ..  ..     12-91 

Soluble  in  hot  water     . .         . .         . .     5097 

Total  nitrogen    ..         ,.         ..         ,.       597 
Albuminoid  nitrogen    ..         ..         ..       4-11 

Caffeine  ,,  .,  ..  ..       0-96 

Amide  ,,  ,.         ..         ..       0-91 

The  table  shows  quite  clearly  the  reduction  in  tannic  acid  which 
the  process  of  fermentation  brings  about  in  black  tea. 

Scott  Tebb*  compared  the  amounts  of  tannic  acid  and  alkaloid 
extracted  from  different  forms  of  tea  (8  grammes  of  the  tea  being 
infused  with  600  c.c.  of  boiling  distilled  water  for  five  minutes)  with 
the  following  results : 

*  'Commercial  Organic  Analysis,'  vol.  iii.,  part  ii. 

'  See  United  States  Department  of  Agriculture,  Division  of  Chemistry, 
Bulletin  13,  1892. 

*  Dried  at  105°  C.  *  As  gallo-tannic  acid. 

*  '  Tea  and  the  Effects  of  Tea  Drinking '  (London :  T.  Cornell  and  Sons 
63,  Borough  Rpa4.  S.E.). 


Green 

Black 

Tea. 

Tea. 

Per  cent. 

Per  cent 

3743 

3890 

1006 

1007 

552 

582 

3143 

3539 

492 

493 

3  20 

330 

10-64 

489 

53  74 

4723 

599 

6  22 

3  94 

411 

093 

096 

113 

1-16 

3i8 


FOOD  AND  DIETETICS 


Class  of  Teas. 

Number  of 
Analyses. 

Per  Cent. 
Extract. 

Per  Cent. 

Alkaloid. 

Per  Cent 

Tannin. 

Indian 

Ceylon 

China 

l8 
12 
13 

26*11 
26-04 
22-12 

2-84 

2-68 
2-40 

7-43 
7-85 
6 -08 

An    analysis   of    the    teas    most    widely    consumed    in    London 
Restaurants  gave  the  following  results  : 

RESTAURANT  TEAS. 
{Infusion  0/  S  grammes  with  600  c.c.  0/  boiling  distilled  water  for  five  minutes.) 


Proportion 

of  T^innin 

No. 

Description  and 

Retail  Price 

Per  Cent. 

Per  Cent. 

Per  Cent. 

Correipond- 

District. 

Per  lb. 

Extract. 

Alkaloid. 

Tannin. 

in=;  to 

2 '3  per  cent. 

Alkaloid. 

I 

"  China"  Tea 

2S.  2d. 

2020 

2-51 

4-85 

5"4i 

2 

Ordinary  Black 

Tea 
"China"  Tea 

2S.  2d. 

2560 

2-04 

903 

12-39 

^ 

2S.  od. 

20-06 

2-15 

3  02 

3  93 

4 

Ordinary  Black 
Tea 

2S.  od. 

2790 

2  69 

974 

10-13 

5 

"  Russian"  Tea 

23.  6d. 

23  "50 

2-30 

5  •36 

6-52 

6 

Ordinairy  Black 
Tea 

28.  8d. 

24  60 

3-02 

6  03 

5-59 

7 

"China"  Tea 

2S.  4d. 

24-50 

222 

5-85 

7'37 

8 

Ordinary  Black 
Tea 

28.   2d. 

28-31 

2-72 

8-44 

8-69 

The  composition  of  tli«  infusion  is  of  much  greater  practical 
importance  than  that  of  the  leaves  from  which  it  is  made. 

If  tea  be  infused  for  five  minutes  in  the  usual  way,  about  25  per 
cent,  of  the  weight  of  the  leaf  goes  into  solution.  In  making  a  large 
teacupful  of  tea  (about  150  c.c,  or  ^  pint),  5  grammes  (about  ^  ounce) 
of  dried  leaf  are  usually  employed,  and  a  cupful  of  such  tea  contains 
in  solution  about  15  grains  of  solid  matter.  The  bulk  of  this  is  made 
up  of  gummy  matters,  extractives,  etc.,  but  the  most  important 
ingredients  are  the  caffeine,  and  tannic  acid. 

The  caffeine  is  so  soluble  that  it  is  practically  all  dissolved  out  of 
the  leaf  immediately  infusion  has  begun.^  With  tannic  acid  this  is 
not  the  case.  There  is  certainly  less  tannic  acid  after  three  minutes' 
infusion  than  after  five,  and  less  after  five  than  after  ten  ;  but 
beyond  that  one  does  not  find  much  increase,  for  by  that  time 
practically  the  whole  of  the  soluble  matters  have  been  extracted 
from  the  leaf.     The  following  experiments  bear  upon  this  point : 

^  The  caffeine  in  the  infusion  is  combined  with  tannin  in  the  form  of  caffeine 
tannate,  in  the  proportion  of  one  of  caffeine  to  three  of  tannin  (see  '  The 
Chemistry,  etc.,  of  a  Cup  of  Tea,'  Lancet,  ii.,  191 1,  p.  1573). 


AMOUNT  OF  TANNIC  ACID  IN  TEA 


319 


Hughes*  found  the  following  proportions  of  tannic  acid  extracted 
in  dijETerent  times  : 


Five  Minutes' 

Thirty  Minutes' 

Infusion. 

Infusion. 

Assam    ..         .. 

•  • 

10-35  per  cent. 

14-76  per  cent. 

Ceylon  .. 

•  • 

860 

IO-88 

China     . . 

.. 

780        ., 

940 

Hale  White2  found : 

Three  Minutes' 

Fifteen  Minutes' 

Infusion. 

Infusion. 

Finest  Assam    . . 

•  • 

11-30  per  cent. 

17  73  per  cent. 

China     .. 

.. 

777 

797 

Common  Congou 

.. 

937 

1115 

(The  figures  represent  percentage  of  tannic  acid  in  weight  of  leaf  used.) 

The  following  results 

were  got  by  Dittman 

; 

Caffeine.           Tannic  Acid 

Per  cent.             Per  cent. 

China    tea  (8    samples)  |  ^ 

minutes'  infusion  .. 

.     2-58                    3-06 
•     2-79                    3-78 

Ceylon  ..   (6         ..       )  {  ^5 

•  •           •• 

•  3-15                     587 

•  329                    730 

Indian    ,,   (12       ..       )  , 

.. 

•    .3-63                    677 

•  I   \           It       '  (  10 

■  I           .1 

•     373                    809 

It  will  be  observed  that  the  proportion  of  tannic  acid  is  much  more 
affected  by  the  length  of  infusion  than  that  of  cafTeine. 

Finally,  one  may  quote  the  experiments  of  Green,'  in  which 
420  c.c.  of  boiling  distilled  water  were  poured  on  3^  grammes  of  tea, 
and  infusion  carried  on  under  a  cosy  for  from  five  to  forty  minutes, 
with  the  following  results  as  regards  the  composition  of  the 
beverage : 


Five 

Ten 

Twenty 

Forty 

Minutes 

Minutes' 

Minutes' 

Minutes' 

Infusion. 

Infusion. 

Infusion. 

Infusion. 

Per  cent. 

Per  cent. 

Per  cent. 

Per  cent. 

Extract  .. 

m.        21    7 

253 

268 

281 

Caffeine             , 

I-l 

i'3 

I  16 

Tannic  acid 

..       6-8 

8-5 

11-7 

i6-3 

Nitrogen 

I'll 

116 

i-ii 

I  04 

Ash 

••       352 

409 

4-15 

4-48 

All  these  experiments  agree  in  showing  that  the  longer  tea  is  in- 
fused the  higher  is  the  proportion  of  tannic  acid  dissolved  out,  while  the 
proportion  of  caffeine,  on  the  other  hand,  is  but  little  affected.  From 
this,  the  practical  inference  is  that,  if  one  wishes  to  avoid  having  much 
tannin  in  tea,  one  should  infuse  it  for  as  short  a  time  as  possible.* 

The  writer  has  made  a  number  of  experiments  with  the  view  of 
determining  the  amount  of  caffeine  and  tannic  acid  present  in  an 

^  Journal  of  Society  of  A  rts,  January  25,  1895.  ^  Brit.  Med.  Journ.,  1889,  i.  91. 

'  Thorpe's  'Dictionary  of  Chemistry.' 

*  It  has  been  suggested  by  the  Lancet  (December  2,  1911)  that  if  a  good  tea 
be  infused  for  not  longer  than  five  minutes  all  the  caffeine  and  tannin  extracted 
will  be  in  the  form  of  caffeine  tannate,  which  is  free  from  the  injurious  effects 
of  free  tannic  acid,  and  is  probably  devoid  also  of  the  ordinau-y  pharmacological 
eflfects  of  pure  caffeine. 


320 


FOOD  AND  DIETETICS 


ordinary  teacupful  of  tea  infused  in  the  usual  way. 
are  contained  in  the  following  tables  : 


The  results 


"  CAFFEINE  IN  TEAS.> 

Caffeine  in 

Tea.  Graynmes 

per  150  c.e. 

Ceylon  Pekoe  00787 

Fine  Darjeeling      ..         ..         ..     00751 

Common  Congou   ..  ..         ..     00745 

Moyune  Gunpowder  (green)        ..     00645 
Imperial  Gunpowder         ..  ..     00590 

Household  blend    ..         ..         ..     00580 

Young  Hyson  ..  ..  ..     C0547 

Fine  Moning  ..  ..  ..     00510 

Fine  Assam o  0475 

TANNIN  IN  TEAS.2 


Tm. 

Moyune  Gunpowder 
Young  Hyson 
Imperial  Gunpowder 
Ordinary  black  blend 
Fine  Darjeeling 
Good  black  blend  . . 
Ceylon  Pekoe 
Lapseng  Souchong 
Fine  Assam  . . 
Fine  Moning 


Tannin  as  GallO' 

tannic  Acid  per 

150  c.c.  0/ Infusion. 

0273 

0242 

0227 

0173 
0168 
0168 
0142 
0087 
o  080 
0058 


Grains 
per 

Teacup. 
I  21 
I  05 
1  14 
099 
090 
089 
084 
078 
073 


Grains 

per 
Teacup. 

4'20 

372 
349 
2-66 
258 
258 
218 

I  33 
I  23 

089 


As  a  rule,  one  may  say  that  a  teacupful  of  tea  of  ordinary 
strength  infused  for  five  minutes  contains  about  i  grain  of  caffeine, 
and  twice  or  three  times  as  much  tannic  acid. 

It  may  be  well  to  give  some  practical  rules  for  the  proper  method 
of  making  tea  based  on  the  facts  as  to  its  chemistry  which  we  have 
just  been  considering.  This  is  all  the  more  important  as  it  is 
comparatively  rare  to  get  a  really  good  cup  of  tea,  in  spite  of  the 
popularity  of  the  beverage.  It  must  be  admitted,  too,  that  the  fault 
lies  oftener  with  the  method  of  infusion  than  with  the  quality  of  the 
original  leaf  employed. 

And,  first,  the  tea  should  really  be  infused,  not  boiled  or  stewed, 
as  is  so  often  the  case.  The  character  of  the  water  is  of  the  first 
importance.  The  Chinese  rule  is,  '  Take  the  water  from  a  running 
stream ;  that  from  hill  springs  is  best,  river  water  is  the  next,  and 
well  water  is  the  worst.'  The  meaning  of  this  is  that  the  water 
should  be  well  aerated.     Prolonged  boiling  makes  it  flat  by  driving 

'  Eight  grammes  of  dry  leaf  were  infused  with  300  c.c.  boiling  water  for  five 
minutes.     The  caffeine  was  estimated  by  Allen's  method. 

*  Eight  grammes  of  the  dry  leaf  were  infused  for  five  minutes  in  300  c.c.  of 
water,  and  the  tannin  estimated  by  Procter's  modification  of  Lowenthal's  procees 


HOW  TO  MAKE  TEA  3«» 

oflF  the  dissolved  air.  Hence,  the  water  should  have  just  freshly 
come  to  the  boil.  If  it  is  already  fiat,  it  is  a  good  plan  to  pour  it 
into  a  jug  from  a  height,  for  this  causes  it  to  take  up  some  air 
again.^ 

The  water  should  not  be  too  hard,  for  the  presence  of  lime  salts 
seems  to  interfere  with  the  extraction  of  some  of  the  constituents  of 
the  leaf.  If  only  hard  water  is  obtainable,  it  is  a  good  plan  to  add 
a  pinch  of  soda  to  the  teapot.  Water  which  is  too  soft  is  also  bad, 
for  it  seems  to  extract  a  bitter  principle  from  the  leaf.  Moderately 
soft  water,  therefore,  is  the  ideal  to  be  aimed  at. 

The  quantity  of  leaf  infused  demands  some  attention.  The 
domestic  rule  of  '  a  teaspoonful  for  each  person  and  one  for  the  pot ' 
is  an  uncertain  one,  for  the  weight  of  a  spoonful  of  tea  is  a  very 
variable'^  quantity,  depending  as  it  does  very  much  on  the  tightness 
with  which  the  leaf  is  rolled. 

Tea-tasters  use  the  weight  of  a  new  sixpence  (43^  grains)  to 
3l^  ounces  of  water,  and  this,  which  is  a  somewhat  smaller  propor- 
tion of  tea  than  that  given  by  the  domestic  rule,  yields  a  more 
satisfactory  though  weaker  infusion.  It  must  be  remembered,  how- 
ever, that  the  popular  taste  is  for  a  strong  beverage  with  a  good 
deal  of  '  body.'* 

The  water,  as  we  have  seen,  should  be  first  brought  to  the  boil, 
and  the  teapot  should  be  thoroughly  heated,  so  that  the  temperature 
may  be  maintained  :  for  it  is  only  at  the  boiling-point  that  some  of 
the  volatile  constituents  of  the  leaf,  to  which  the  beverage  owes  its 
aroma,  can  be  properly  extracted. 

Infusion  should  be  of  limited  duration — not  more  than  four  or  five 
minutes,  for  prolonged  treatment  extracts  too  much  tannic  acid,  and 
withdraws  from  the  leaf  also  bitter  substances  which  are  better  left 
behind.  In  addition  to  this,  prolonged  infusion  dissipates  the  volatile 
oil  to  which  much  of  the  fragrance  of  a  good  cup  of  tea  is  due. 
The  use  of  a  '  cosy '  during  infusion  does  no  harm,  but  as  soon  as 
the  process  is  completed  the  liquor  should  be  poured  off  into  another 
hot  teapot,  which  may  then  be  kept  covered  if  desired. 

The  addition  of  milk  or  cream,  though  an  outrage  in  the  eyes  of 

^  The  Chinese  directions  for  preparing  the  water  are  as  follows :  '  The  fire  must 
be  lively  and  clear,  but  the  water  must  not  be  boiled  too  hastily.  At  first  it 
begins  to  sparkle  like  crabs'  eyes,  then  somewhat  hke  fishes'  eyes,  and  lastly  it 
boils  up  like  pearls  innumerable,  springing  and  waving  about.' 

^  The  weight  of  a  caddy  spoonful  varies  from  39  to  87  grains  (Smith). 

'  For  the  economical  preparation  of  good  tea  the  thorough  crushing  of  the  lea, 
is  of  great  importance,  so  that  its  ingredients  may  readily  be  extracted.  Ttu 
powdered  tea  of  Japan  is  ideal  in  this  respect,  and  in  this  country  the  '  ter 
tabloids  '  recently  introduced  are  deserving  of  a  word  of  praise  for  the  same  reaso-. 

21 


3aa  FOOD  AND  DIETETICS 

connoisseurs,  is  to  be  commended  on  hygienic  grounds,  for  the 
albuminous  matter  of  the  milk  tends  to  throw  down  some  of  the 
tannic  acid  of  the  tea  in  an  insoluble  form.  Sugar  does  not  in  any 
way  increase — indeed,  it  may  detract  from — the  healthfulness  of  the 
beverage,  but  adds  considerably  to  its  nutritive  value. 

All  second  brews  should  be  avoided,  for  a  single  infusion  is 
sufficient  to  remove  from  the  leaves  all  the  useful  constituents  of  the 
beverage. 

Coffee. 

Coffee  was  introduced  into  this  country  in  the  year  1652  by  a 
certain  Mr.  Daniel  Edwards,  a  retired  Smyrna  merchant,  who  set 
up  his  Greek  servant  in  a  coffee-house,  the  first  of  its  kind  in 
London,  in  St.  Michael's  Alley,  Cornhill.  As  a  beverage  it  has 
never  attained  the  popularity  with  us  that  it  has  won  on  the 
Continent,  for  at  the  present  day  we  consume  less  than  a  pound  of  it 
per  head  of  the  population  annually,  whereas  in  Holland  the  con- 
sumption amounts  to  21  pounds.  This  may  be  explained  partly, 
perhaps,  by  the  fact  that  we  do  not  know  how  to  make  coffee,  but 
mainly  by  its  great  expense  when  compared  with  its  principal 
rival,  tea. 

Coffee  is  derived  from  the  Caffcea  arabica,  originally  produced,  as 
the  name  implies,  in  Arabia,  but  now  cultivated  in  many  tropical 
countries.  The  plant  produces  three  harvests  annually,  the  fruit 
resembling  a  cherry,  in  which  the  '  coffee-bean '  corresponds  to  the 
stone.  The  bean  consists  of  two  halves  placed  face  to  face  and 
enclosed  in  a  husk.  The  pulp  is  softened  by  fermentation  and 
removed,  and  the  beans,  still  enclosed  in  their  husk,  are  dried  in  the 
air.  The  husk  is  separated  by  rolhng,  and  the  beans  are  then 
separated  from  the  delicate  parchment-like  skin  which  covers  them, 
and  assorted  according  to  size. 

Several  varieties  of  bean  are  found  on  the  market,  the  chief  being 
as  follows  :^ 

1.  Mocha. — The  genuine  beans  of  this,  the  finest  sort  of  coffee,  are 
derived  from  Arabia  Felix,  but  much  so-called  Mocha  coffee  is  really 
produced  elsewhere,  chiefly,  perhaps,  in  Guatemala.  Two  varieties 
are  met  with,  *  long  berry '  and  *  short  berry.'  The  former  are 
grayish -yellow  in  colour,  and  give  a  rich,  mellow  liquor.  The  latter 
are  pale  greenish -yellow,  and  give  a  clearer  and  more  delicate 
infusion  (Bannister). 

2.  Mysore. — Here  again  the  name  is  apt  to  mislead,  for  the  majority 

^  Bannister's  Cantor  Lectures,  1890, 


VARIETIES  OF  COFFEE 


3*3 


of  coffees  of  this  name  come  from  Java  and  Ceylon.     The  berry  is 
bluish-gray  in  colour  and  yields  a  pure,  strong  and  clear  liquor. 

3.  Ceylon  Plantation. — The  berry  is  of  a  pale  greenish  tint,  and 
yields  a  clear  beverage  of  full  but  smooth  flavour  and  fair  body. 
This  coffee  is  largely  used  for  blending. 

4.  Cesta  Rica. — A  bluish-gray  berry  yielding  a  strong  but  rather 
coarse  liquor. 

5.  Java. — A  very  fine  coffee,  with  large,  pale,  oblong  berries 
yielding  a  strong,  clear  liquor. 

6.  Brazil. — A  coffee  of  peculiar  flavour,  used  chiefly  for  mixing 
with  other  varieties. 

In  order  to  prepare  the  beverage,  the  berries  must  first  be  roasted. 
The  composition  of  raw  and  roasted  coffee  is  thus  contrasted  by 
Bannister : 


Caffeine 

Saccharine  matter        . . 

Caffeic  acids 

Alcoholic  extract  (nitrogenous 
and  colouring  matters) 

Fat  and  oil  

Legumin 

Dextrin 

Cellulose  and  insoluble  colour- 
ing matter       

Ash  

Moisture 


Mocha. 


Raw. 


I  08 

955 
846 

690 

I2"60 

9-87 

087 

3795 
374 

898 


Roasted. 


o-8a 
043 
474 

1414 

1359 
11-23 

1-24 

4862 
456 
063 


East  Indian. 


Raw. 


8-90 
958 

431 
irSi 
11-23 

084 

386 
398 
964 


Roasted. 


105 
041 

4'5* 

12-67 

13-41 

13-13 

1-38 

47-4« 
4-88 
113 


The  chief  physical  change  which  results  from  roasting  is  that  the 
berries  are  rendered  brittle  and  can  now  be  ground.  Chemically, 
one  finds  that  they  lose  from  13  to  20  per  cent,  of  their  weight,  the 
loss  consisting  in  nearly  equal  parts  of  moisture  and  organic  matter. 
The  lost  organic  matter  includes  about  21  per  cent,  of  the  total 
caffeine  and  10  per  cent,  of  the  fat.^  If  the  coffee  is  'over-roasted,' 
the  loss  of  caffeine  may  be  considerably  greater. 

The  most  important  substance  produced  in  the  coffee  by  roasting 
is  an  oil,  caffeol,  to  which  the  aroma  of  roasted  coffee  is  due,  and  the 
fragrance  of  which  is  so  powerful  that  one  drop  is  said  to  be 
Sufficient  to  scent  a  whole  room. 

1  Analyst,  p.  287,  1S97,  See  also  'The  Chemistry  of  a  Cup  of  Coflee,"  Lancet, 
iu,  1913,  P-  1563- 


324  FOOD  AND  DIETETICS 

Composition  of  the  Infusion. 

From  25  to  35  per  cent,  of  the  coffee  used  in  making  the  infusion 
goes  into  solution.  This  percentage  of  solubility  is  about  the  same 
as  that  of  tea,  but  seeing  that  a  much  larger  quantity  of  coffee  is 
taken  than  of  tea,  the  amount  of  solids  per  cup  is  considerably 
higher  in  the  former  than  in  the  latter  beverage.  If  2  ounces  be 
used  to  make  a  pint,  a  teacupful  of  the  beverage  will  contain  in 
solution  about  4-2  grammes  of  solids,  of  which  0*65  is  mineral 
matter.  This  is  supposing  the  coffee  to  be  filtered.  As  ordinarily 
drunk,  some  suspended  matter  must  also  be  included. 

An  analysis  which  I  have  made  of  coffee  of  the  above  strength, 
showed  the  presence  of  1*7  grains  of  caffeine  per  teacupful,  and  3*24 
grains  of  tannic  acid.^  According  to  this  result,  a  cup  of  black  coffee 
contains  very  much  the  same  amount  of  caffeine  and  tannic  acid  as 
an  equal  quantity  of  tea.'  A  breakfast-cupful  of  cafe  au  lait  is  com- 
posed of  about  I  part  of  black  coffee  to  3  of  milk,  and  will  not, 
therefore,  contain  more  of  the  alkaloid  than  a  teacuptul  of  tea. 

French  coffee  demands  a  special  word  of  mention.  It  usually 
contains  more  or  less  chicory,  and  sometimes  also  some  burnt  sugar. 
Chicory  is  the  root  of  the  wild  endive,  kiln-dried  and  broken  into 
fragments.  The  process  of  drying  converts  its  sugar,  of  which  it 
may  have  10  to  18  per  cent.,  into  caramel.  There  is  no  reason  to 
believe  that  chicory  is  in  any  way  injurious  to  health,  but  i  pound 
of  it  is  equal  in  colouring  power  to  2-8  pounds  of  coffee,  and  as  a 
pound  of  chicory  costs  3^d.,  while  a  pound  of  coffee  costs  about 
IS.  5d.,  it  is  evident  that  3^d.  worth  of  the  former  is  equal,  as  far  as 
the  mere  appearance  of  the  beverage  goes,  to  3s.  1  id.  worth  of  the 
latter.  Hence  the  great  temptation  to  adulterate  coffee  with  chicory, 
a  process  which  has  done  much  to  discourage  the  consumption  of 
coffee  in  this  country.  As  a  rule,  French  coffee  contains  about  one- 
third  of  its  weight  of  chicory,  but  sometimes  the  proportion  may  be 
as  high  as  80  per  cent.,  or  even  more. 

The  secret  of  having  good  coffee  is  to  make  it  strong  and  to  make 
it  hot.  We  mostly  fail  in  this  country  by  not  using  enough.  Two 
ounces  to  the  pint  is  the  smallest  proportion  which  will  give  a  good 
result.  It  is  important  that  the  coffee  should  be  freshly  roasted,  for 
its  fragrance  is  quickly  dissipated  on  keeping,  and  in  roasting  one 
must  see  that  the  beans  are  of  the  same  size ;  otherwise  they  will  be 
unequally  fired.     For  this  reason  mixing  should  be  carried  out  after 

^  Reckoned  as  gallo-tannic. 

2  Lehmann  {Munch.  Med.  IVoch.,  Nos.  6  and  7,  1913)  found  that  if  15  grammes 
of  coffee  are  used  to  make  150  c.c.  of  the  beverage,  the  solution  contains  from 
0'15  to  o'4  gramme  of  caffeine. 


COCOA  325 

roasting,  and  not  before.  Care  also  must  be  taken  that  the  grinder 
is  quite  clean,  for  if  any  stale  coffee  is  left  in  it  the  whole  may  be 
spoilt.  The  water  should  be  just  boiling,  and  infusion  may  be 
carried  out  either  in  a  jug  or  in  a  porcelain  percolator.  For  break- 
fast coffee  a  mixture  of  coffees — e.g.,  half  and  half  Mocha  and  Planta- 
tion— may  be  used,  and  the  addition  of  a  little  ground  chicory  is 
liked  by  some,  but  for  black  coffee  the  latter  should  always  be 
omitted.  Three  parts  of  milk  to  one  of  coffee  is  about  the  proper 
proportion  for  cafe  an  lait. 

Cocoa. 

Cocoa  was  first  brought  to  Europe  from  Mexico  by  Columbus  in 
the  year  1520.  It  was  known  at  that  time  as  '  cacao,'  but  the  name 
got  changed  with  the  lapse  of  time.  Although  introduced  consider- 
ably earlier  than  either  tea  or  coffee,  it  is  only  of  late  years  that  it 
has  attained  any  wide  popularity,  and  that  chiefly  through  the 
energy  and  enterprise  of  some  of  its  manufacturers. 

The  cocoa-plant  is  the  Theobroma  cacao,  the  fruit  of  which  resembles 
a  vegetable  marrow  or  cucumber.  Embedded  in  the  pulp  of  the 
fruit  are  many  seeds,  each  about  the  size  of  a  haricot  bean,  and  it 
is  from  these  that  cocoa  is  prepared.  The  seeds  are  separated  from 
the  pulp,  and  placed  in  heaps  for  several  days  to  ferment,  or  *  sweat.' 
This  causes  any  adherent  pulp  to  become  loose,  and  at  the  same 
time  modifies  the  bitterness  of  the  seeds  and  produces  in  them  a 
dark  colour.  They  are  then  roasted,  which  renders  them  brittle 
and  loosens  the  husk,  so  that  the  two  halves  of  the  seed  come  out 
separately  on  pressure  in  a  machine  as  cocoa-nibs. 

The  nibs  are  either  sold  as  such  or  are  ground  between  hot 
rollers,  which,  by  melting  the  fat  that  they  contain,  reduces 
them  to  a  fluid  condition.  Most  of  the  fat  is  removed  by  pressure, 
and  the  remainder  of  the  cocoa  is  then  run  into  moulds,  from  which 
it  is  removed  as  slabs.  For  conversion  into  '  soluble  cocoa '  or  *  cocoa 
essence '   the  slabs  are  again  ground  down  to  an  impalpable  powder. 

Various  names  are  applied  to  different  preparations  of  cocoa. 
The  method  of  preparing  soluble  cocoa  has  just  been  described ; 
but  it  should  be  noted  that  the  term  is  really  a  misnomer,  for, 
strictly  speaking,  there  is  no  such  thing  as  a  soluble  form  of  cocoa. 
All  that  the  term  implies  is  that  the  powder  is  so  finely  divided  that 
it  easily  remains  in  a  state  of  suspension  when  mixed  with  water. 
In  order  to  aid  the  suspension,  various  methods  of  treating  the 
cocoa  are  sometimes  adopted.  The  addition  of  alkali  is  a  favourite 
device,  especially  with  Dutch  manufacturers.  It  aids  suspension  by 
saponifying  and  emulsifying  the  fat,  and  at  the  same  time  softens  the 


326  FOOD  AND  DIETETICS 

fibre  of  the  cocoa,  so  that  it  can  form  a  sort  of  pulp  with  water.  It 
also  has  the  efifect  of  deepening  the  colour  of  the  beverage,  and  so  of 
making  it  look  stronger.  The  free  addition  of  alkali  is  objected  to 
by  some  as  being  injurious  to  health,  but  it  is  very  doubtful  if  that 
can  be  fairly  alleged  against  it.  There  are  also  methods  of  increasing 
the  solubility  of  cocoa  by  the  aid  of  heat,  and  to  these  no  objection 
can  be  urged. 

The  term  homoeopathic  cocoa  is  sometimes  applied  to  mixtures  of 
cocoa  with  other  substances,  such  as  arrowroot. 

Malted  cocoa  is  a  combination  of  pure  cocoa  with  extract  of  malt. 

Navy  cocoa  is  one  of  the  purest  preparations  of  the  article,  being 
quite  free  from  husk.  The  ordinary  form  contains  20  per  cent,  of 
Demerara  sugar,  whilst  the  '  soluble '  form  has  20  per  cent,  of  white 
sugar  and  20  per  cent,  of  arrowroot.  Both  forms  are  to  be  regarded 
as  preparations  of  chocolate  rather  than  mere  cocoa. 

Chemical  Composition  of  Cocoa,^ — The  general  composition  of  the 
cocoa-bean  is  shown  in  the  following  table  (Bannister) : 

COMPOSITION  OF  COCOA. 

A  nalysis  of  Raw  Analysis  of 

Trinidad  Nibs  Shelled  Fresh 

(Inland  Revenut  Cocoa-beans 

Laboratory).  (Boussingault). 

Water        • 523  76 

Fat 5044  499 

Starch         ..         ..         ..         ..       420  3-^ 

Albuminous  matter,  soluble      . .       6-3  I 

,,             ,,           insoluble  ..       69  j        " 

Astringent  principle        ..         ..       671  o"2 

Gum           217  2*4 

Cellulose    ..         ..         ..         ..       640  io'6 

Alkaloid      ..         ..          ..          ..       084  3-3 

Cocoa-red  . .  . .  . .         . .       2  20 

Undetermined       ..         ..         ..       5  So  5-3 

Ash  ..         2  75  40 

The  chief  ingredient  is  fat,  of  which  the  cocoa-bean  contains  about 
half  its  weight.  In  the  commercial  powder,  however,  there  is  only 
about  32  per  cent,  present,  the  remainder  having  been  removed  by 
pressure. 

Cocoa  contains  a  considerable  proportion  of  nitrogen,  but  it  must 
be  carefully  noted  that  not  more  than  21  per  cent.  (Wigner)  to 
32  per  cent.  (Stutzer)  of  this  is  present  as  proteins,  the  rest  being 
in   the   form  of  amides.     Part  also  is  contained  in    theobromine. 

>  For  much  information  on  this  subject  and  full  bibliography,  see  Unit«i  States 
Department  of  Agriculture,  Division  of  Chemistry,  Bull.  13  ;  also  a  paper  by 
Cohn,  Ztit.  f.  Physiolog.  Chem.,  1895,  xx.  i.  See  also  Allen's  '  Commercial  Organic 
Analysis,'  vol.  iii.,  part  ii. 


COMPOSITION  OF  COCOA 


327 


Cohn,  indeed,  found  only  7*9  per  cent,  of  true  protein  in  raw 
cocoa-beans,  using  Stutzer's  method. 

The  chief  alkaloid  found  in  cocoa  is  theobromine.  Theohromine 
is  known  chemically  as  dimethyl-xanthin,  and  it  is  closely  related  to 
caffeine,  which  is  methyl-theobromine.  Cocoa  contains  from  i  to  2 
per  cent,  of  it,  or  about  as  much  as  there  is  of  caffeine  in  coflfee. 

Cocoa  contains  also  some  tannin,  though  probably  not  of  exactly 
the  same  form  as  that  found  in  coflfee  and  tea.  Zipperer^  places  the 
amount  at  5*4  per  cent.  It  seems  to  be  combined  with  a  pigment 
to  which  the  name  of  cocoa-red  is  given,  but  the  exact  relationship 
of  the  two  substances  has  not  been  fully  determined. 

Starch  is  present  to  the  extent  of  5*78  to  15' 13  per  cent.  (Ewell). 

The  proportion  of  mineral  matter  is  high,  amounting  in  raw  cocoa 
to  from  2^  to  3^  per  cent.  After  the  fat  has  been  partly  removed, 
the  proportion  of  ash  rises  to  4  or  5  per  cent. ;  or,  if  alkali  has  been 
artificially  added,  it  may  amount  to  8  per  cent.  The  ash  is  strongly 
alkaline,  and  in  the  artificial  preparations  consists  chiefly  of  potash 
and  phosphoric  acid. 

The  following  table  contains  the  results  of  some  analyses  which 

the  writer  has  made  of  the  commonest  forms  of  cocoa  in  use  in  this 

country : 

COMPOSITION  OF  COCOAS. 


Cadbury's  Cocoa  Essence 
Fry's  Pearl  Cocoa     . . 

,,     Pure      ,, 
Van  Houten's  Pure  Cocoa 
Vi-Cocoa 

Schweitzer's  Cocoatina 
Rowntree's  Elect  Cocoa 
Epps's  Prepared  Cocoa 
Suchard's  Cocoa 
Clarnico  Cocoa         . . 


Mois- 

Fat 

ture. 

39 

252 

73 

15-8 

5-6 

256 

30 

280 

6-3 

269 

43 

282 

6-5 

255 

49 

151 

47 

332 

5'i 

30-6 

Nitrogenous 

Matter 
(NX6-25). 


209 

43 

197 
205 
170 
19-4 
180 
67 
186 
22 'O 


Non-Nitro- 
genous 
Con'itituentS 
other  thau 
Fat. 


45-2 

712 
43-2 
39  7 
43-8 
41-8 
422 
718 

367 
36T 


Ash. 


4-8 
1-4 
59 

8-8 
70 

6-3 

7-8 

1-5 
6-8 

59 


Average  Composition  0/ a  Pure  Soluble 
Cocoa. 

Moisture 4  per  cent. 

Nitrogenous  matter       ..  20        ,, 

Fat  26        „ 

Other    non  •  nitrogenous 

matter   ..         ..      ...  40        ,, 

Mineral  matter   . .         . .      6        „ 


Probable  Percentage  of  Nutrients  in  such 
a  Cocoa, 


Protein     . . 

Fat 

Carbohydrates 


12  per  cent. 

26 

25         ..  (?) 


*  Quoted  by  Cohn  {loc.  cit.).    See  also  FrsLser,  Journ.  of  Anat.  and  Physiolog., 
1883,  xviii.  13,  and  Wynter  Blyth,  '  Foods,'  4th  edit.,  p.  455. 


328 


FOOD  AND  DIETETICS 


Special  attention  may  be  directed  to  the  fact  that  there  is  no 
preparation  of  pure  cocoa  which  is  much  poorer  in  fat  than  any 
other.^ 

The  following  additional  analyses  are  by  Ewell': 


Fat. 

Fibre. 

Cane- 
sugar. 

Ash. 

424 

633 
864 
606 
848 
1-66 

Added 

Starch. 

Fry's  Cocoa  Extract 
Schweitzer's  Cocoatina 
Van  Houten's  Cocoa 
Blocker's  Dutch  Cocoa 
Rowntree's  Cocoa  Extract 

,,          Powdered  Chocolate 

3095 
3113 
2981 

31-48 
2756 

25  84 

389 
370 
438 
376 
442 
1-30 

51 

None 

Very"    littla 
arrowroot 

Epps's  Prepared  Cocoa 

2594 

I  51 

26 

315 

Much  arrow- 

Fry's  Diamond    Sweet  Choco- 
late 

i860 

0  81 

55 

I  16 

Much  wheat 
starch  and 

some 
arrowroot 

London  Cocoa  (unknown  maker) 

1113 

2  13 

32 

2  82 

Much  arrow- 
root 

Chocolat  Menier 

21-31 

I    10 

58 

1-40 

None 

Chocolate  consists  of  ground  cocoa  from  which  the  fat  has  not 
been  removed,  mixed  with  white  sugar,  starch  and  flavourings,  such 
as  vanilla,  being  often  added.  The  inferior  varieties  are  made  from 
unfermented  beans,  and  therefore  have  a  bitter  taste.  Good  choco- 
late should  melt  easily  in  the  mouth,  and  should  not  sweat  out  any 
sugar  in  the  form  of  a  bloom.  The  taste  also  should  be  free  from 
any  roughness  or  astringency.  The  white  part  of  chocolate  creams 
consists  of  a  mixture  of  melted  cane-sugar  and  glucose. 
•  The  foJ  lowing  are  some  analyses  of  chocolate  : 


Water. 

Nitrogenous 
Matter. 

Fat. 

Carbo- 
hydrate. 

Aih. 

Chocolat  de  Sante' 

.     10-3 

12-5 

471 

26-8 

3 '3 

Van  Houten's  Chocolate"* 

3'9 

27"5 

668 

1-8 

Plain  Chocolate*     .. 

1-89 

7-85« 

21-2 

61-9' 

1-9 

Milk  Chocolate*      . . 

1-22 

939 

2998 

5737 

2-04 

Plasmon  Chocolate* 

.          2-36 

18-14 

30-36 

4546 

2-68 

^  Neumann  (Arch.  f.  Hyg.,  1906,  Iviii.  i)  concludes  that  cocoas  with  about 
30  per  cent,  of  fat  are  to  be  preferred  on  all  grounds  to  those  with  less.  They 
also  have  the  advantage  of  remaining  longer  in  suspension  than  those  which  are 
poorer  in  fat. 

■^  Allen's  '  Commercial  Organic  Analysis,'  vol.  iii,,  pan  ii, 

*  Analysis  by  Atwater  and  Woods. 

*  Analysis  by  the  author. 

*  Analysis  in  Leyden's  '  Handbuch,'  i.  109. 

*  1  "67  =  theobromine. 

'  7'4  =  non-nitrogenous  extractives. 

*  Analysis  by  Jago  {Journ.  of  the  Soc.  oj  Arts,  January  10,  igoa). 


INFUSED  BEVERAGES  AND  DIGESTION         3^9 

Chocolate  was  first  used  as  a  beverage  in  this  country  about  1657. 
It  was  very  popular  in  the  time  of  Charles  II.,  and  fetched  6s.  5d. 
per  pound. 

Influence  of  Tea,  Coffee,  and  Cocoa  on  Digestion. 

The  influence  of  these  beverages  on  salivary  and  gastric  digestion 
is,  on  the  whole,  unfavourable ;  of  their  effects  on  intestinal  digestion 
we  have  little  exact  knowledge ;  Roberts  considers  that  they  are 
practically  nil.  Roberts^  found  that  tea  markedly  inhibits  the  con- 
version of  starch  into  sugar  by  the  saliva.  If  there  was  even  5  per 
cent,  of  tea  infusion  in  the  digesting  mixture,  practically  no  digestion 
of  starch  took  place.  He  attributes  this  result  entirely  to  the  tannic 
acid  in  the  infusion,  but  found  that  tea  infused  for  only  two  minutes 
had  quite  as  powerful  an  effect  as  when  the  infusion  was  prolonged 
for  half  an  hour.  He  points  out  that  the  addition  of  a  pinch  of 
bicarbonate  of  soda  to  the  teapot  completely  suspends  the  inhibitory 
effect.  Aitchison  Robertson^  confirms  these  observations  as  regards 
tea,  but  found  that  coffee  had  much  less  influence,  and  cocoa  almost 
none  at  all. 

The  most  elaborate  investigation  of  the  action  of  these  beverages 
on  digestion  in  the  stomach  has  been  made  by  Fraser.^  He  found 
that  tea  and  coffee  both  retard  peptic  digestion,  but  the  former  to  a 
greater  degree  than  the  latter,  and  that  Indian  tea  has  a  more 
powerful  effect  than  China.  Further,  his  observations  brought  out 
the  interesting  result  that  the  digestion  of  different  articles  is  retarded 
in  unequal  measure.  Thus,  the  digestion  of  white  of  egg,  ham,  salt 
beef,  and  roast  beef,  was  much  less  affected  than  that  of  lamb,  fowl, 
or  bread.  Coffee,  indeed,  seemed  actually  to  aid  the  digestion  of 
egg  and  ham.  He  points  out  that  the  foods  first  mentioned  are  those 
most  commonly  eaten  at  breakfast,  the  meal  with  which  tea  and 
coffee  are  usually  taken,  and  he  sees  in  this  an  unconscious  adapta- 
tion to  obviate  any  disturbance  of  digestion.  He  attributes  the 
retarding  effect  to  the  tannic  acid  and  volatile  oil  which  these 
beverages  contain,  the  caffeine  itself  favouring  digestion  rather  than 
otherwise.  The  addition  of  milk,  it  is  important  to  note,  largely 
removed  the  retarding  influence  of  tea.  Fraser  also  found  that  tea 
increased  the  production  of  gas  from  all  except  the  salted  foods. 
Coffee  did  not  do  this,  and  therefore,  he  says,  should  be  preferred  to 
tea  in  cases  of  flatulent  dyspepsia.    Tea  also  reduces  the  acid-absorb- 

1  '  Digestion  and  Diet,*  p.  120. 

•  Robertson,  W.  G.  A.,  Journ.  0/  Anat.  and  Physiolog.,  1898,  xxxil  613. 

•  Ibid.,  1883,  xviii.  13. 


330  FOOD  AND  DIETETICS 

ing  power  of  foods ;  coffee  has  a  similar  but  less  marked  effect, 
while  cocoa  actually  increases  it.  For  this  reason  cocoa  is  the  most 
appropriate  beverage  for  patients  suffering  from  the  acid  forms  of 
dyspepsia. 

Cocoa  was  found  to  interfere  with  artificial  digestion,  owing  to  the 
'  clogging '  action  of  its  fine  particles  preventing  the  free  access  of 
gastric  juice  to  the  food.  It  is  very  doubtful,  however,  whether  it 
would  have  any  such  effect  under  natural  conditions. 

The  retarding  influence  of  tea  and  coffee  on  peptic  digestion  has 
been  also  established  by  Roberts,^  Ogata,^  and  Schultz-Schultzen- 
stein.3  The  former  is  of  opinion  that  the  tannic  acid  only  accounts 
for  about  one-half  of  the  inhibitor}'  effects  exerted  by  tea.  On  the 
whole,  they  are  agreed  that  coffee  has  less  influence  than  tea,  pro- 
vided it  be  of  the  same  strength,  but,  inasmuch  as  the  former  is 
usually  a  stronger  infusion  than  the  latter,  its  effects  in  actual  practice 
are  equally  powerful. 

Apart  from  their  modifying  influence  on  the  chemical  processes  of 
digestion,  it  must  be  remembered  that  these  beverages  sometimes 
affect  the  stomach  more  directly.  Thus,  the  tannic  acid  and  other 
astringent  substances  met  with  in  strong  infusions  of  tea  may  act  as 
irritants  to  the  mucous  membrane  of  the  stomach,  especially  if 
empty  ;  and  the  same  is  true  to  an  even  greater  extent  of  the  caffeol 
and  other  products  produced  in  the  roasting  of  coffee.  It  is  in  this 
way  that  these  beverages  may  sometimes  excite  or  keep  up  a  con- 
dition of  chronic  gastric  catarrh.  Cocoa  also,  owing  to  the  large 
proportion  of  fat  which  it  contains,  is  apt  to  be  irritating  to  some 
stomachs,  especially  as  the  fat  of  cocoa  appears  to  be  one  which  is 
rather  difficult  of  digestion. 

As  regards  the  practical  inferences  to  be  drawn  from  these  experi- 
ments and  observations,  it  may  be  said  that  in  health  the  disturbance 
of  digestion  produced  by  the  infused  beverages  is  negligible. 
Roberts,  indeed,  goes  so  far  as  to  suggest  that  the  slight  slowing  of 
digestion  which  they  produce  may  be  favourable  rather  than  other- 
wise, as  tending  to  compensate  for  too  rapid  digestibility  which 
refinements  of  manufactvure  and  preparation  have  made  a  charac- 
teristic of  modern  foods. 

In  cases  where  the  digestion  is  enfeebled,  on  the  other  hand,  and 
where  the  ferments  are  doing  their  work  with  difficulty,  the  presence 
of  these  beverages  in  the  digesting  mass  may  make  all  the  difference 
between  failure  and  success  in  the  process.     In  such  a  case,  coffee 

*  Loc.  at.  ■•*  Archiv.  f.  Hygient,  1885,  iii.  204. 

•  Zeit.  f.  Physiolog.  Ckem.,  1894,  ^tviii  131. 


USES  OF  TEA,  COFFEE,  AND  COCOA  33 » 

is  probably  preferable  to  tea,  and  cocoa  (provided  its  fat  does  not 
prove  a  disturbance)  is  better  than  either.  If  tea  is  taken  at  all,  a 
good  China  variety  should  be  selected ;  it  should  be  infused  for  as 
short  a  time  as  possible,  and  should  be  taken  with  milk.^  Second 
cups  should  be  eschewed,  and  it  should  be  drunk  after,  rather  than 
during,  the  meal. 

Tea  and  coffee  should  both  be  avoided — but  especially  the  former 
— as  an  accompaniment  to  meals  which  make  large  demands  on  tht 
peptic  powers  of  the  stomach,  such,  for  example,  as  meals  containing 
much  meat.  For  this  reason  *  high '  and  '  meat '  teas  are  to  be 
condemned.  In  chronic  catarrh  of  the  stomach,  coffee  is  probably 
more  injurious  than  tea,  but  in  cases  of  flatulence  the  former  is  to  be 
preferred  for  the  reasons  already  given.  As  has  been  previously 
pointed  out,  the  irritating  effects  of  these  beverages  on  the  stomach 
are  more  likely  to  be  manifested  when  the  latter  is  empty.  For  this 
reason,  the  morning  cup  of  tea  may  sometimes  prove  harmful.  On 
the  whole,  the  effects  are  probably  least  when  the  stomach  is  neither 
quite  empty  nor  too  full,  but  contains  a  moderate  amount  of  easily- 
digested  food — a  state  of  things  which,  one  is  glad  to  say,  is  pretty 
well  true  at  '  afternoon  tea.' 

As  concerns  the  length  of  stay  of  these  beverages  in  the  stomach, 
the  following  observations  have  been  made : 

200  c.c.  (ij  teacups)  of  tea  remain i|  hours 

„  I,  ,,        coffee  remain  . .  ..  ..  ..  i^     ,, 

I,          ,,          „        cocoa  made  with  water  remain     ..  i|     ,, 
,,            ,,        milk         ,,          ..  2I     ,, 

In  other  words,  the  larger  the  amount  of  solid  matter  which 
the  beverage  contains,  and  the  more  it  approximates  to  the 
characters  of  a  true  food,  the  longer  does  it  tend  to  remain  in 
the  stomach. 

There  are  no  available  observations  on  the  absorption  of  tea  and 
coffee.  If  no  to  120  grammes  (about  4  ounces)  of  cocoa  are  taken 
daily,  the  loss  of  nitrogenous  matter  is  about  46  per  cent.,  but  of  the 
fat  only  4*6  per  cent,  escapes  digestion.  The  carbohydrates  are 
entirely  absorbed. 2  If  more  than  50  grammes  (ten  teaspoonfuls) 
were  taken  at  a  time,  digestion  was  always  upset. 

1  The  addition  of  a  little  bicarbonate  of  soda  to  the  contents  of  the  teapot 
helps  to  neutralize  the  injurious  effects  of  the  tannic  acid.  The  same  result  is 
attained  in  •Plasmon  tea  '  by  the  incorporation  of  soluble  casein  with  the  leaf, 
which  '  detannates  '  the  infusion. 

2  Cohn,  loc.  cit.  Weigimann  found  that  the  fat  was  absorbed  to  94*5  per  cent., 
and  the  nitrogenous  matter  to  42  per  cent.,  when  195  grammes  of  cocoa- powder 
boiled  in  water  were  taken  in  two  days.  Neumann  {Arch,  f,  Hyg.,  1906,  Iviii.  i) 
found  that  cocoa,  when  given  alone,  is  not  nearly  so  well  absorbed  as  whea  it 


33a  FOOD  AND  DIETETICS 

Uses  of  Tea,  Coffee  and  Cocoa. 

The  action  of  tea  and  coffee  on  the  body  depends  entirely  upon  the 
tannic  acid,  caffeine  and  volatile  oil  which  these  beverages  contain. 
The  effects  of  the  tannic  acid  are  purely  local,  and  have  already 
been  pointed  out,  when  speaking  of  the  iniiuence  of  tea  and  coffee 
on  digestion.  The  caffeine  and  volatile  oil,  on  the  other  hand,  have 
a  general  pronounced  physiological  action,  to  which  attention  must 
now  be  directed. 

Caffeine,  like  alcohol,  is  a  stimulant,  but,  unlike  that  substance,  it 
exerts  its  effects  upon  the  central  nervous  system  even  more  than 
upon  the  heart.  Physiological  experiments  have  shown  that  after 
the  administration  of  caffeine  the  time  occupied  by  nervous  processes 
is  shortened,  and  reflex  excitability  is  increased.  At  the  same  time, 
it  removes  the  sense  of  fatigue,  and  is  apt  to  produce  sleeplessness. 
It  is  interesting  to  note  that  these  stimulating  effects  upon  the  brain 
were  amongst  the  earliest  of  the  physiological  actions  of  tea  and 
coffee  to  be  recognised.  Tradition  has  it  that  in  the  remote  ages 
there  was  a  holy  Asiatic,  Prince  Darma,  who  spent  his  nights  in 
meditation  on  the  Infinite.  One  night  his  ecstasy  was  disturbed  by 
sleep.  On  waking,  he  was  so  enraged  at  his  weakness  that  he  cut 
off  his  eyelids  and  flung  them  on  the  ground.  On  visiting  the  spot 
some  time  later,  he  found  that  where  each  eyelid  fell  a  small  shrub 
had  grown  up.  He  infused  the  leaves  of  the  shrub,  and  ever  after- 
wards, by  simply  drinking  some  of  the  infusion,  he  was  able  to  keep 
sleep  at  bay.     That  shrub  was  the  tea  plant ! 

A  similar  tradition  as  regards  the  stimulating  effects  of  coffee  is 
thus  recorded  by  Johnston  :^ 

'  In  antique  days  a  poor  dervish,  who  lived  in  a  valley  of  Arabia 
Felix,  observed  a  strange  hilarity  in  his  goats  on  their  return  home 
every  evening.  To  find  out  the  cause  of  this,  he  watched  them 
during  the  day,  and  observed  that  they  eagerly  devoured  the  blossoms 
and  fruit  of  a  tree  which  hitherto  he  had  disregarded.  He  tried  the 
effect  of  this  food  upon  himself,  and  was  thrown  into  such  a  state  of 
exaltation  that  his  neighbours  accused  him  of  having  drunk  of  the 
forbidden  wine.     But  he  revealed  to  them  his  discovery,  and  they  at 

forms  part  of  a  mixed  diet.  When  added  to  a  mixed  diet,  it  lessens  the  absorption 
of  nitrogen  from  the  latter,  and  the  less  fat  the  cocoa  contains  the  more  marked 
is  this  effect.  The  protein  of  the  cocoa  can  replace  part  of  the  protein  in  the  rest 
of  the  diet.  Cocoa  can  therefore  claim  to  rank  as  a  food,  although  not  an 
important  one.  In  the  quantities  taken  (20  to  30  grams  per  day)  it  had  no  diuretic 
•fiiect,  and  the  theobromine  was  only  agreeably  stimulating. 
*  'Physiology  of  Common  Life,'  p.  i^'6- 


ACTION  OF  CAFFEINE  333 

once  agreed  that  Allah  had  sent  the  coffee-plant  to  the  faithful  as  a 
substitute  for  the  vine.' 

As  a  result  of  this  action  on  the  nervous  system,  tea  and  coffee 
are  great  aids  to  mental  work,  and  the  former,  as  De  Quincey 
remarked,  will  always  be  the  beverage  of  the  intellectual  As  a 
learned  Chinaman  said  of  it  more  than  2,000  years  ago : 

•  It  tempers  the  spirits  and  harmonizes  the  mind. 
Dispels  lassitude  and  relieves  fatigue  ; 
Awakens  thought  and  prevents  drowsiness, 
Lightens  or  refreshens  the  body,  and  clears  the  perceptive  faculties.' 

The  vital  centres  share  in  the  stimulation  produced  by  caffeine,  as 
well  as  the  brain  cortex.-  After  its  administration,  the  respiratory 
movements  are  deeper  and  more  frequent,  and  the  heart  beats  more 
forcibly  and  rapidly.  It  is  thus  an  important  aid  in  combating 
impending  paralysis  of  these  centres  in  cases  of  coma.  Binz,  for 
example,  found  that  dogs  which  had  been  rendered  comatose  by 
alcohol  could  be  aroused  after  the  administration  of  coffee.  The 
fact  that  coffee  is  an  antidote  to  alcohol  is  another  justification  for  its 
use  after  dinner. 

Caffeine,  as  we  have  seen,  stimulates  the  heart  through  the  cardiac 
centre,  but  it  probably  has  a  direct  action  as  well.  When  adminis- 
tered in  the  form  of  tea  and  coffee,  its  action  is  aided  by  the  fact 
that  these  beverages  are  usually  taken  hot.  The  increased  force 
and  frequency  of  the  heart's  action  induces  a  more  profuse  flow  of 
urine,^  and  so  aids  in  the  removal  of  waste  products  from  the  body. 
This,  along  with  the  stimulation  of  the  nervous  system  and  heart, 
makes  tea  and  coffee  of  use  in  some  low  forms  of  fever,  conditions  in 
which  their  administration  might  with  advantage  be  more  extensively 
adopted. 

The  question  has  been  much  debated  whether  or  not  caffeine 
lessens  the  waste  of  the  body.  Some,  for  instance,  have  contended 
that  it  acts  as  a  kind  of  drag  upon  the  chemical  changes  in  the 
tissues,  rendering  them  slower,  and  so  enabling  the  body  to  get  on 
with  less  food  than  would  otherwise  be  necessary.  For  this  con- 
tention, however,  there  is  no  satisfactory  evidence.  Indeed,  all 
experiments  go  to  prove  the  contrary,  namely,  that  caffeine  tends  to 
increase  rather  than  diminish  tissue  waste.^  It  does  not  prolong  life 
in  starvation,  although  it  may  perhaps  lessen  the  feeling  of  hunger. 
Experiments  with  the  ergograph,  too,  have  shown  that  tea  and 
coffee  are  in  no  sense  muscle  foods,  although  they  can  temporarily 

*  Caffeine  appears  to  have  a  dirtct  stimulating  action  on  the  renal  cells  as  well. 

•  See  Richet's  '  Dictionary  of  Physiology,'  article  '  Caffeine.' 


334  FOOD  AND  DIETETICS 

increase  muscular  power  by  abolishing  nervous  fatigue,  so  long,  at 
least,  as  the  muscles  are  not  completely  exhausted.^ 

The  action  of  the  volatile  oil  contained  in  tea  and  coflfee  has  not 
been  very  fully  investigated,^  and  would  appear  to  be  slightly 
different  in  the  case  of  the  two  beverages.  It,  too,  appears  to  act  as 
a  cerebral  and  cardiac  stimulant,  and  to  it,  perhaps,  some  of  the 
unpleasant  symptoms,  such  as  headache  and  giddiness,<Hvhich  afflict 
those  who.  like  tea-tasters,  indulge  in  large  quantities  of  these 
beverages  are  to  be  attributed. 

These  oils  seem  also  to  have  an  action  upon  the  bloodvessels 
which  is  different  in  the  case  of  tea  and  coffee  respectively,  for  the 
former  tends  rather  to  dilate  the  superficial  vessels  and  render  the 
skin  moist,  while  coffee  has  an  opposite  action.  It  is  in  this  way 
that  tea  is  said  to  warm  the  body  when  cold,  by  making  the  circula- 
tion more  brisk,  and  to  cool  it  when  heated,  by  increasing  evapora- 
tion from  the  surface. 

We  may  conclude,  then,  that  tea  and  coffee  are  in  no  sense  foods, 
in  that  they  can  neither  build  up  the  tissues  nor  provide  them  with 
potential  energy,  though  they  may  perhaps  act  the  parts  of  lubricants 
in  the  machinery  of  the  body  by  diminishing  nervous  fatigue.  It 
is  no  doubt  this  subjective  feeling  which  has  led  to  the  very 
extended  use  of  these  beverages  by  men  in  all  ages  and  in  all 
countries. 

When  we  turn  to  the  question  as  to  what  extent  these  beverages 
can  be  indulged  in  without  injury  to  health,  one  finds  it  very  difficult 
to  give  a  definite  reply.  The  part  played  by  personal  peculiarity 
and  habit  in  the  matter  is  very  great.  It  has  been  pointed  out,  for 
example,  that  the  usual  result  of  drinking  tea  and  coffee  is  to  produce 
wakefulness,  but  yet  there  are  persons  who  find  their  use  in  the 
evening  conducive  to  sleep.  Some  people,  again,  can  drink  tea 
quite  freely,  but  are  made  ill  by  coffee  or  vice  versa.  Facts  like 
these  must  be  recognised  although  one  is  unable  to  explain  them, 
and  they  make  it  impossible  to  lay  down  definite  rules  regarding  the 
dietetic  use  of  tea  and  coffee. 

The  bad  effects  usually  attributed  to  an  excessive  indulgence  in 
these  beverages  are  of  two  kinds,  affecting  either  the  nervous  system 
or  the  digestion.  The  increased  excitability  of  the  nervous  system 
which  they  produce  may  lead  to  general  '  nervousness '  (the  patient 
starts,  for  instance,  on  the  slightest  sudden  noise,  or,  as  a  tea-taster 

1  Schumburg,  Arckiv.  f.  Anat.  und  Physiolog.,  1899,  Sup.  Bd.  289.  See  also 
Rivers  and  Webber, /ottrn.  of  Physiolog.,  1907,  xxxvi.  33. 

2  The  tendency  of  recent  investigations  is  to  minimize  the  importance  of  the 
volatile  oil  in  tea.  or  even  to  throw  doubt  upon  its  ejustence  {vidt  Scott Tebb,  loc.cit.). 


FOOD  VALUE  OF  COCOA  335 

once  put  it  to  the  writer,  he  becomes  'jumpy'),  tremulousness, 
palpitation,  loss  of  sleep,  giddiness,  and  depression.  The  nervous 
system  in  childhood  is  peculiarly  susceptible  to  these  effects. 

The  disturbance  of  digestion  which  tea  or  coffee,  but  especially 
the  former,  produces  is  partly  due  to  a  direct  interference  with  the 
chemical  part  of  the  process,  as  already  described,  but  in  part  also 
is  brought  about  indirectly  through  the  nervous  system.  The 
dyspepsia  which  results  is  of  the  atonic  type,  digestion  being 
slow,  often  accompanied  by  flatulence  and  attended  by  a  feeling  of 
sinking  or  depression  and  disturbance  of  the  heart's  action. 

Whilst  one  may  fully  admit  the  importance  of  the  part  played  by 
tea  and  coffee  in  the  production  of  such  symptoms,  yet  the  extent  to 
which  they  prevail  has  probably  been  greatly  overestimated.*  It 
certainly  seems  an  exaggeration  to  talk,  as  some  people  do,  of  the 
existence  of '  tea  drunkenness.'  All  that  one  is  entitled  to  infer  is 
that  these  beverages  should  be  used  sparingly  by  '  nervous '  people 
and  by  those  whose  digestion  tends  to  be  feeble  and  slow. 

In  some  cases  of  gout  it  is  advisable  to  strike  tea  and  coffee  out  of 
the  diet,  for  caffeine  is  a  source  of  uric  acid  in  the  body.  Theobromine 
is  so  too,  but  cocoa  contains  so  little  of  it  that  it  is  practically 
harmless.2 

The  place  of  cocoa  in  the  diet  is  not  really  very  different  from  that 
of  tea  and  coffee.  An  examination  of  the  chemical  composition  of 
cocoa  might  lead  one  to  suppose  that  it  was  of  considerable  nutritive 
value.  But  that  would  be  a  mistake.  Theoretically,  cocoa  is  a 
valuable  food,  but  practically  it  is  not,  the  reason  being  that  so  little 
of  it  can  be  taken  at  a  time.  In  this  respect  it  is  exactly  com- 
parable to  many  of  the  beef-extracts  already  considered.  The  com- 
bination of  cocoa  with  casein — as  in  Plasmon  Cocoa — increases  the 
nutritive  value  of  the  beverage  to  a  considerable  extent. 

It  takes  about  10  grammes  {\  ounce)  of  cocoa  to  make  a  breakfast- 
cupful  of  the  beverage,  and,  assuming  the  average  composition  given 
already,  this  would  yield  about  40  Calories  of  energy.  It  would, 
therefore,  require  fully  seventy-five  such  cupfuls  to  yield  the  total 
amount  of  potential  energy  demanded  of  the  body  daily — obviously 
an  impossible  quantity.  Of  course,  if  the  beverage  is  prepared 
entirely  with   milk  and  plenty  of  sugar  it  becomes  an  important 

1  For  an  account  of  the  symptoms  which  may  result  from  an  excessive 
indulgence  in  coffee  see  a  paper  by  Dr.  William  M.  Leszynsky  {Med.  Record, 
1901,  lix.  41,  70).  See  also  a  paper  on  '  Tea  and  the  Effects  of  Tea  Drinking,' 
by  Dr.  W.  Scott  Tebb  (Cornell  and  Sons,  Borough  Road,  S.E.) ;  and  Gouget, 
'  Le  Cafeisme  et  le  Theisme  '  {Gaz.  des  Hop.,  1907,  Ixxx.  1623). 

^  Sanitas  Health  Cocoa  contains  no  theobromine  (sold  by  Battle  Creek 
Sauitarium  Co.,  Ltd.,  Battle  Creek,  Michigan,  U.S.AJu 


336  FOOD  AND  DIETETICS 

food,  but  that  is  due  to  the  milk  and  sugar,  and  not  to  the  cocoa. 
Chocolate  is  of  more  value.  Half  a  pint  of  milk  and  2  ounces  of 
chocolate  yield  together  fully  400  Calories,  and  3^  pints  would 
suffice  to  supply  all  the  energy  and  a  large  part  of  the  building 
material  required  in  a  day. 

The  action  of  cocoa  on  the  nervous  system  is  very  much  less  than 
that  of  tea  or  coffee,  owing  to  the  small  amount  of  alkaloid  which  it 
contains  ;  indeed,  it  may  be  practically  ignored.  The  special  prepara- 
tion known  as  Vi-Cocoa,  on  the  other  hand,  has  an  influence  on 
the  brain  from  the  addition  to  it  of  a  certain  proportion  of  kola. 
The  latter  contains  a  considerable  proportion  of  caffeine  as  well  as 
a  glucoside  (kola-red),  and  it  is  to  these  ingredients  that  its  action 
on  the  nervous  system  is  to  be  attributed.^  Kola  is  said  to  possess 
remarkable  sustaining  qualities,  prolonging  muscular  contraction 
and  abolishing  fatigue ;  but  its  action  seems  to  be  uncertain,  and  the 
addition  of  such  a  drug  to  a  beverage  intended  to  be  used  regularly 
is  a  practice  which  can  hardly  be  recommended. 

Paraguay  Tea.' 

Paraguay  tea  or  mate  belongs  to  the  holly  order.  It  contains  a 
small  quantity  of  caffeine  along  with  a  peculiar  form  of  tannic  acid, 
glucosides,  choline,  and  ethereal  oils.  It  yields  a  pale  infusion  of 
somewhat  bitter  and  harsh  flavour.  It  is  stated  to  be  even  more 
stimulating  and  sustaining  than  tea  or  coffee,  and  less  apt  to  cause 
indigestion  and  sleeplessness. 

Owing  to  the  injurious  effects  of  tea  and  coffee  on  the  digestion 
and  nervous  system  in  some  persons,  various  substitutes  for  them 
in  the  diet  have  been  proposed.  Amongst  these  are  Ovaltine,  which 
is  composed  of  malt  extract,  milk,  eggs  and  cocoa,  and  which  con- 
tains a  considerable  percentage  of  lecithin.  It  contains  12-3  per 
cent,  fat,  60  per  cent,  of  carbohydrates,  13-4  per  cent,  protein,  and 
3-5  per  cent,  ash.^  Life-Belt  Coffee  (coffee  from  which  the  caffeine 
has  been  extracted)  and  Cocacom  (a  combination  of  acorns  and 
cocoa)  are  other  tea  and  coffee  substitutes.  Various  Cereal  Coffees, 
made  from  parched  grains  of  barley,  wheat,  etc.,  are  also  prepared, 
especially  in  America.  One  or  other  of  these  substitutes  is  some- 
times found  of  use  in  replacing  tea  or  coffee  when  these  are  forbidden 
on  medical  grounds. 

*  See  Brit.  Med.  Journ.,  189S,  i.  1471  ;  Food  and  Sanitation,  February  9,  1895; 
David  tmile,  These,  Paris,  1894  ;  Labesse,  These.  Paris,  1S97. 

^  Paraguay  Tea  can  be  obtained  from  the  Apothecaries'  Society,  Blackfriars, 
at  a  cost  of  2s.  6d.  per  pound.  Also  from  the  Mate  Tea  Co.,  4,  Featherstone 
Buildings,  High  Holborn,  W.C. 

»  Brit.  Med.  Journ.,  January  i,  1910. 


[337  J 


CHAPTER  XIX 

ALCOHOL 

The  only  form  of  alcohol  with  which  we  are  seriously  concerned  in 
dietetics  is  ethyl  alcohol  (CjHgOH).  It  is  produced,  in  all  the 
beverages  in  which  it  is  found,  from  the  fermentation  of  sugar  by 
yeast,  according  to  the  well-known  equation  : 

C«HuO,   =    aCOj     +    aCjHgOH. 
^  (sugar)        (carbonic        (alcohol). 

acid) 

We  shall  subsequently  discover  that  the  special  characters  of 
different  alcoholic  beverages  depend  to  some  extent  on  the  particular 
kind  of  sugar  and  yeast  concerned  in  the  fermentation.  It  must 
also  be  borne  in  mind  that  the  process  of  fermentation  as  carried  on 
in  the  manufacture  of  alcoholic  drinks  is  never  such  a  simple  affair 
as  the  above  equation  might  induce  one  to  believe.  Bye-products 
are  invariably  produced  as  well  as  alcohol,  and  the  nature  and 
amount  of  these  profoundly  influence  the  character  of  the  resulting 
beverage.  Of  all  alcoholic  drinks,  however,  it  remains  true  that  the 
principal  constituent  by  which  they  affect  the  nutrition  of  the  body 
is  ethyl  alcohol.  It  consequently  becomes  of  the  first  importance 
for  us  to  study  minutely  the  effects  of  alcohol  on  the  body,  for  upon 
the  results  of  such  study  our  opinion  as  to  the  value  or  otherwise  of 
alcoholic  drinks,  both  in  health  and  disease,  must  ultimately  rest. 
I  propose,  therefore,  to  devote  this  chapter  to  a  description  of  the 
physiological  effects  of  alcohol. 

Local  Effects  of  Alcohol. 

The  local  effects  of  alcohol  are  those  of  a  chemical  irritant.  If 
some  strong  spirit,  such  as  whisky  or  brandy,  is  taken  into  the 
mouth,  a  sensation  of  burning  is  produced,  owing  to  the  irritation  of 
the  nerve  endings,  and  by-and-bye  the  mucous  membrane  becomes 
somewhat  corrugated  and  whitened  by  reason  of  the  removal  of 
water  from  its  surface  cells  and  the  coagulation  of  their  protoplasm. 

32 


338  FOOD  AND  DIETETICS 

Repeated  local  irritation  of  this  sort  is  the  exciting  cause  of  the 
pharyngitis  and  gastric  catarrh  often  observed  in  those  who  are  in 
the  habit  of  drinking  neat  spirits,  especially  on  an  empty  stomach, 
where  the  alcohol  can  come  into  direct  contact  with  the  mucous 
membrane.  The  stimulation  of  the  nerves  of  the  mouth  brings 
about  reflexly  a  profuse  flow  of  saliva,  and  in  this  way  alcohol  may 
promote  salivary  digestion,  for  its  retarding  influence  in  the  chemical 
transformation  of  starch  into  sugar  is  so  slight  that  it  may  be 
neglected.* 

Effects  of  Alcohol  on  Digestion.' 

Arrived  in  the  stomach,  alcohol  mixes  with  the  gastric  contents, 
and  affects  the  processes  of  digestion  in  several  very  important 
directions.  The  first  point  to  notice  is  that  alcohol  has,  by  itself, 
surprisingly  little  influence  on  the  chemical  processes  of  digestion. 
When  it  is  present  to  the  extent  of  only  i-2  per  cent,  of  the  digesting, 
mixture,  its  influence  is  rather  favourable  than  otherwise.  If  the 
proportion  of  alcohol  is  increased  to  5  or  10  per  cent,  the  chemical 
changes  of  digestion  become  retarded,  but  it  is  only  when  20  per 
cent,  of  alcohol  is  present  that  the  process  is  arrested  altogether.^ 

This  immunity  of  pepsin  to  the  action  of  alcohol  is  very  striking, 
and  as  a  consequence  of  it  one  cannot  regard  pepsin  wines  as 
irrational  products  of  pharmacy.  It  is  interesting  to  note  that 
pancreatic  digestion  is  much  more  sensitive  to  alcohol,  tor  if  the  latter 
be  present  to  the  extent  of  onl)  2  or  3  per  cent.,  the  process  is 
distinctly  retarded.  But  digestion  is  not  merely  a  chemical  process. 
The  movements  of  the  stomach  walls  play  a  large  part  in  it  also.  And 
here  the  action  of  alcohol,  in  dietetic  doses  at  least,  is  entirely 
favourable,  for  it  has  a  wonderful  power  of  increasing  the  activity 
of  stomach  peristalsis.  Binz,  for  example,  found  that  the  ad- 
ministration of  eight  small  teaspoonfuls  of  brandy  at  short  intervals, 
for  the  space  of  an  hour,  increased  very  considerably  the  rate  at 
which  olive  oil  was  discharged  from  the  stomach.  He  repeated  the 
experiment  with  similar  results  in  six  cases. 

Alcohol  not  merely  increases  the  vigour  of  the  stomach  move- 

'  The  presence  of  even  45  per  cent,  of  alcohol  does  not  altogether  stop 
ainylolytic  action  (Roberts).  This  is  confirmed  by  Aitchison  Robertson  and  by 
Chittenden  and  Mendel. 

*  For  an  exhaustive  stuay  of  this  subject  see  '  The  Influence  of  Alcohol  and 
Alcoholic  Beverages  on  TJigestion  and  Secretion,'  by  Dr.  R.  H.  Chittenden 
('  Physiological  Aspects  of  the  Liquor  Problem,'  vol.  I.  ;  Boston  and  New  York  : 
Houghton,  Mifflin  and  Co.,  1903,  p.  137). 

*  See  Buchner,  Deut.  Archiv.  f.  Klin.  Med.,  188 1,  xxix.  537.  See  also  Chitt^n. 
den  and  Mendel,  of.  cit.  infra. 


ALCOHOL  AND  DIGESTION  339 

ments :  it  promotes  very  powerfully  the  secretion  of  gastric  juice.* 
This  it  does  not  merely  by  directly  irritating  the  nerves  of  the 
mucous  membrane,  but  also  indirectly  by  its  presence  in  the  blood 
after  absorption.  This  indirect  action  of  alcohol  is  of  great  im- 
portance, for  it  means  that  even  when  all  the  alcohol  swallowed 
has  left  the  stomach,  and  when  any  slight  retarding  influence  which 
it  may  have  exerted  on  the  merely  chemical  processes  of  digestion 
has  ceased,  it  is  still  able  to  afTect  the  disintegration  of  the  food  by 
bringing  about  a  more  profuse  and  sustained  flow  of  the  digestive 
juices. 2 

When  one  weighs  the  very  slight  retarding  influence  of  alcohol  on 
the  chemical  part  of  digestion  against  its  power  of  promoting  the 
stomach  movements  and  the  flow  of  gastric  juice,  one  finds  that  the 
balance  is  favourable  to  digestion,  and  alcohol  must  therefore  be 
regarded  as  a  digestive  stimulant.  In  accordance  with  this,  direct 
experiment  on  the  human  subject  has  shown  that  alcohol  in  dietetic 
quantities,  e.g.,  30  to  40  grammes  of  brandy  (about  two  tablespoon- 
fuls),  taken  before  or  during  meals,  actually  shortens  the  time 
required  for  the  digestion  of  a  meal  by  about  half  an  hour.^  Red 
wines  were  found  to  have  a  similar  effect. 

The  net  influence,  then,  of  moderate  doses  of  alcohol  upon 
stomach  digestion,  even  in  health,  is  favourable  rather  than  the 
reverse,  while  in  some  conditions  of  disease  its  power  of  exciting  the 
movements  of  the  walls  of  the  stomach  and  of  promoting  the  flow  of 
gastric  juice  render  it  a  valuable  aid  to  the  digestion  of  solid  food. 
On  the  other  hand,  it  is  to  be  noted  that  in  intoxicating  doses 
alcohol  interferes  with  digestion,  owing  to  the  general  nervous  and 
vascular  depression  which  it  brings  about. 

The  importance  of  these  conclusions  regarding  the  influence  of 
alcohol  on  digestion  can  hardly  be  overrated,  for  they  explain  much 
of  the  benefit  which  is  so  often  derived  from  the  moderate  use  of 
alcohol,  even  in  health,  and  still  more  in  cases  of  disease. 

Unlike  water,  alcohol  is  freely  absorbed  by  the  mucous  membrane 
of  the  stomach.  Chittenden  and  Mendel  found  that  when  the 
pylorus  was  ligatured  200  c.c.  of  a  37  per  cent,  solution  of  alcohol 
disappeared  from  the  stomach  of  a  dog  in  about  three  hours,  and 

1  For  some  very  valuable  experiments  on  this  subject  see  Chittenden  and 
Mendel,  American  Journal  of  the  Medical  Sciences,  1896.  N.S.,  iii.  35,  163,  314,  431, 
and  American  Journal  of  Physiology,  1898,  i.  164.  Full  references  are  given  in 
these  papers  to  the  results  of  other  workers. 

*  The  gastric  juice  is  not  merely  increased  in  quantity.  The  proportion  of  its 
solids  and  its  acidity  are  raised  as  well  (Chittenden  and  Mendel). 

'  Penzoldt  and  Wolflhardt,  Miinch.  Med.  Woch..  1890,  xxxvii.  608, 


340  FOOD  AND  DIETETICS 

they  add  that  one  may  well  believe  that  when  6  or  8  grammes  of 
alcohol  are  swallowed  in  the  form  of  wine  or  beer,  80  to  90  per  cent, 
of  it  will  have  entered  the  blood  within  half  an  hour.  This  is  of 
great  importance,  for  it  means  that  alcohol  requires  no  digestion,  but  is 
able  to  pass  at  once  into  the  blood.  Hence  much  of  its  value  as  a  rapid 
restorative,  even  when  all  digestive  power  is  in  abeyance.  Alcohol 
is  not  only  rapidly  absorbed  from  the  stomach  itself,  but  power- 
fully promotes  the  absorption  of  other  substances.  If,  for  example, 
a  dose  of  chloral  dissolved  in  water  be  injected  into  a  stomach  the 
pylorus  of  which  is  occluded,  narcosis  does  not  follow,  but  if  even 
very  little  alcohol  is  present  the  usual  soporific  results  soon  set  in. 
It  is  probably  for  this  reason  that  sleeping-draughts  are  often  much 
more  rapid  in  their  effects  when  given  along  with  a  glass  of  whisky 
or  brandy,  and  the  rapid  action  of  medicines  in  the  form  of  tinctures 
may  be  explained  in  the  same  way. 

The  passage  of  alcohol  out  of  the  stomach  into  the  blood  is 
counterbalanced  by  a  flow  of  water  from  the  blood  into  the  stomach. 
The  '  endosmotic  equivalent,'  as  it  is  called,  of  absolute  alcohol  for 
animal  membranes  is  4*13,  and  this  means  that  for  every  gramme  of 
alcohol  which  passes  in  one  direction  4*13  grammes  of  water 
pass  in  the  other.  If,  then,  alcohol  be  administered  to  a  patient 
with  a  dilated  stomach,  the  result  may  be  that  the  total  amount  of 
fluid  in  the  organ  is  ultimately  increased. 

On  the  absorption  of  foods  in  the  intestine  alcohol  in  moderate 
quantity  does  not  seem  to  exercise  any  effect  ';^  in  other  words,  one 
may  digest  his  food  better  for  taking  a  certain  amount  of  alcohol  at 
meals,  but  he  will  not  get  any  more  nourishment  out  of  it. 

Alcohol  as  a  Stimulant. 

The  Latin  word  stimulus  means  a  whip  or  spur,  and  a  stimulant  is 
anything  which  is  capable  of  spurring  on  an  organ  to  the  performance 
of  more  work.  As  a  general  rule,  it  may  be  said  that  stimulants  act 
either  upon  the  nervous  system  or  upon  the  heart,  and  alcohol  is  one 
which  affects  the  latter  much  more  than  the  former.  It  is  doubtful, 
indeed,  whether  alcohol  can  properly  be  regarded  as  a  nervous 
stimulant  at  all.  Any  symptoms  of  increased  brain  activity  which 
it  induces  are  probably  to  be  regarded  as  the  consequence  of  an 
increased  flow  of  blood  through  the  brain  rather  than  as  the  result 
of  any  direct  action  upon  the  cerebral  cells. 

The  stimulating  action  of  alcohol  upon  the  heart,  on  the  other 

'  Zuntz  and  Magnus  Levy,  Pfluger'i  Atchiv.,  1891,  xlix.  438,  and  ibid.,  1893, 
Uii.  544. 


ALCOHOL  AS  A  STIMULANT  34^ 

hand,  is  one  of  the  greatest  importance,  and  results,  in  health,  not 
only  in  a  greater  frequency  of  contraction,  but  also  in  an  increased 
force  of  each  beat.  In  disease,  however,  when  the  heart  is 
beating  rapidly,  but  feebly  and  ineffectually,  the  effect  of  alcohol  is 
often  to  diminish  the  number  of  the  beats  while  improving  their 
force,  and  as  long  as  these  effects  are  being  produced  in  a  case  of 
acute  illness,  one  is  tolerably  safe  in  assuming  that  alcohol  is  doing 
good. 

The  stimulating  effect  of  alcohol  on  the  heart  would  appear  to  be 
exerted  even  before  absorption  has  had  time  to  take  place,  probably 
through  the  medium  of  the  nerves  of  the  stomach,  which  are,  as  is  well 
known,  in  very  close  relation  to  those  which  control  the  action  of  the 
heart.  Sometimes,  indeed,  this  reflex  action  is  so  powerful  that  it 
actually  leads  to  a  stoppage  of  the  heart  altogether.  This  would 
seem  to  be  the  explanation  of  those  cases  of  sudden  death  which 
occasionally  ensue  upon  the  swallowing  of  large  quantities  of  strong 
spirits  on  an  empty  stomach,  as,  for  example,  when  a  man  drinks  a 
pint  of  whisky  for  a  wager. 

After  its  absorption  into  the  blood,  alcohol  is  able  to  affect  the 
heart  more  directly,  while  at  the  same  time  it  brings  about  a  dilata- 
tion of  the  bloodvessels  on  the  surface  of  the  body,  and  so  diminishes 
the  resistance  to  the  onward  flow  of  the  blood.  That  this  diminution 
of  resistance  is  not,  however,  the  sole  cause  of  the  increased  rapidity 
of  the  heart's  action  is  shown  by  the  fact  that  alcohol  can  raise  the 
pulse-rate  even  although  the  bloodvessels  have  been  already  allowed 
to  dilate  by  previous  division  of  the  spinal  cord.  The  action  on  the 
heart,  then,  is  a  direct  one. 

Of  many  observations  illustrating  these  effects  of  alcohol  on  the 
circulation  I  would  only  cite  one  by  Parkes  and  Wollowicz,  who 
found  in  the  case  of  a  man  that  the  administration  of  from 
I  to  7^  ounces  of  rectified  spirit  daily  raised  the  pulse-rate  by 
ten  beats  per  minute  as  compared  with  the  period  when  no  alcohol 
was  being  taken.  They  found,  moreover,  as  other  observers  have 
found  before  and  since,  that  this  overactivity  of  the  heart  was 
followed  by  a  period  of  depression  in  which  the  beat  was  both  slower 
and  feebler  than  normal.  It  is  important  to  bear  in  mind  this  after- 
action of  alcohol.  It  means  that  the  temporary  benefits  obtained 
from  its  stimulating  action  have  to  be  paid  for  by  subsequent  cardiac 
depression,  for  alcohol  is  not,  apparently,  a  food  for  the  heart,  but 
merely  a  means  of  enabling  that  organ  to  draw  for  the  time  being  on 
its  reserve  of  strength.  It  should  be  a  warning,  too,  not  to  begin 
the  administration  of  alcohol  too  early  in  a  case  of  acute  disease, 


342  FOOD  AND  DIETETICS 

lest  one  arrives  at  the  period  when  no  further  stimulation  is  possible 
before  the  crisis  is  past.^ 

It  has  been  said  that  alcohol  tends  to  dilate  the  peripheral  blood- 
vessels. This,  indeed,  is  amongst  its  leading  physiological  actions, 
and  one  the  significance  of  which  it  would  be  difficult  to  overrate, 
for  it  explains  many  of  the  apparently  contradictory  effects  of  alcohol 
on  the  body.  There  is  reason  to  believe,  for  instance,  that  alcohol 
tends  to  anaesthetize  rather  than  stimulate  the  brain,  but  by  dilating 
the  cerebral  bloodvessels  it  may  so  flush  the  brain  with  blood  that 
intellectual  activity  may  be  temporarily  increased  before  the  anaes- 
thetic effects  have  had  time  to  manifest  themselves.  Thackeray  is 
said  to  have  remarked  that  he  got  some  of  his  best  thoughts  '  when 
driving  home  from  dining  out  with  his  skin  full  of  wine.'  We  need 
not  doubt  it,  for  the  statement  embodies  a  physiological  truth.  It 
was  his  skin  which  was  full  of  wine,  for  alcohol  dilates  the  surface 
bloodvessels,  and  along  with  them  those  of  the  brain  also,  but  by  the 
time  he  got  home  one  may  expect  that  the  anaesthetic  effects  of  the 
alcohol  would  have  begun  to  exert  themselves  and  the  thoughts 
would  have  fled.  By  flushing  the  brain  with  blood,  alcohol  may 
produce  temporary  excitement  and  aid  the  imagination,  but  it  ends 
by  dulling  the  edge  of  the  intellect,  and  is  unfavourable  to  sustained 
mental  work. 

Another  apparent  inconsistency  in  the  action  of  alcohol  which  is 
explained  by  its  effects  on  the  bloodvessels  is  its  influence  on  the 
temperature  of  the  body.  Alcohol,  as  we  shall  see  immediately,  is  a 
fuel,  and  by  its  oxidation  in  the  tissues  produces  heat,  just  as  it  does 

*  Since  the  above  was  written  several  more  observations  on  the  action  of  alcohol 
on  the  heart  and  circulation  have  been  published,  the  results  of  which,  however, 
are  far  from  uniform.  Swientochowski  {Zeit.  f.  Klin.  Med.,  xlvi.  284,  1904)  found 
that  after  the  administration  of  25  to  100  c.c.  of  alcohol  of  50  per  cent,  strength 
the  pulse-rate  is  increased,  but  slows  down  again  a  little  in  two  or  three  minutes, 
without  reaching  the  normal  again,  however,  for  at  least  half  an  hour.  For  an  hour 
after  its  administration  blood-pressura  is  lowered.  He  found  no  evidence  that  it 
really  stimulated  the  heart,  but  believes  that  the  latter  is  depressed  by  alcohol,  as 
are  all  vital  functions.  Cabot  (Boston  Med.  and  Surg.  Journ.,  1904,  cl.  281)  is 
convinced  from  his  observations  on  patients  that  no  effect  of  alcohol  upon  the 
heart  or  blood-pressure  is  demonstrable,  although  he  does  not  go  so  far  as  to 
infer  that  it  is  useless  in  disease. 

Dixon,  chiefly  as  the  results  of  experiments  on  rabbits,  arrives  at  the  following 
conclusions  {Journ.  0/ Physiol.,  1907,  xxxv.  346) : 

1.  In  moderate  doses  and  well-diluted  alcohol  has  little  effect  on  the  rate  of  the 
heart ;  in  large  doses  it  slows  the  heart  through  the  vagus.  The  failing  heart  is 
accelerated  by  alcohol.  When  taken  by  the  mouth  and  in  concentration  it 
reflexly  quickens  the  beat. 

2.  In  moderate  doses  it  causes  dilatation  of  the  superficial  vessels  and  some 
slight  constriction,  which  after  large  doses  is  followed  by  dilatation,  of  internal 
vessels. 

3.  In  moderate  doses  alcohol  increases  the  activity  and  output  of  the  heart. 


ALCOHOL  AND  BODY  TEMPERATURE  343 

in  a  spirit-lamp ;  but  by  dilating  the  surface  bloodvessels  it  causes 
more  heat  to  be  given  off  by  radiation  than  its  own  combustion 
produces,  so  that  the  net  result  is  that  the  temperature  of  the  body 
is  lowered.^  It  is  all  the  more  essential  to  grasp  this  fact,  for  the 
reason  that  the  very  flushing  of  the  skin  with  blood  produces  a 
deceptive  feeling  of  warmth,  and  for  that  reason  alcohol  is  often 
taken  *to  keep  out  the  cold.'  That  is  a  great  mistake.  Alcohol 
does  not  '  keep  out  the  cold,'  but  lets  out  the  heat  of  the  body,  and 
consequently  the  consumption  of  spirits  is  a  very  bad  means  of 
fortifying  one's  self  to  meet  a  low  external  temperature,  as  was 
found  out  by  the  Arctic  explorers  long  ago.  By  unlocking  the 
surface  bloodvessels  and  allowing  of  the  escape  of  heat,  alcohol  often 
renders  great  service  in  the  treatment  of  fevers ;  but  in  health  the 
paralysis  of  the  heat-regulating  mechanism  which  it  induces  may 
be  dangerous,  or  even  fatal,  and  ;e  finds  as  a  matter  of  fact  that 
persons  who   are   frozen   to  death,  in   this  country  at   least,  have 

(He  suggests  that  this  may  be  due  to  its  action  as  a  food.)  In  intoxicating  doses 
it  depresses  the  heart. 

4.  When  administered  to  animals  which  show  signs  of  circulatory  failure, 
alcohol  raises  blood-pressure  mainly  on  account  of  its  effect  on  the  heart.  Ie 
normal  animals  and  in  man,  whilst  the  systolic  pressure  may  rise  a  little  01 
remain  unchanged,  the  diastolic  tends  to  diminish  ;  in  other  words,  the  difference 
between  the  systolic  and  diastolic  pressures  tends  to  increase. 

Abel  {•  Physiological  Aspects  of  the  Liquor  Problem,'  edited  by  John  S. 
Billings;  Boston  and  New  York:  Houghton,  Mifflin  and  Co.,  ii.  91)  summarizes 
the  experimental  evidence  regarding  the  action  of  alcohol  on  the  vascular 
apparatus  as  follows : 

'  I.  Alcohol  as  such,  when  introduced  into  the  circulation  with  the  avoidance 
of  local  irritation,  is  not  a  circulatory  "  stimulant." 

'  2.  Alcohol  in  moderate  quantities — say  a  pint  of  wine — has  no  direct  action 
on  the  heart  itself,  either  in  the  way  of  stimulation  or  depressing  it.  This  state- 
ment is  based  on  the  results  of  laboratory  experiments  extending  over  short 
periods  of  time  only,  and  does  not  imply  that  it  holds  for  the  steady  daily  use  of 
alcohol  in  this  quantity. 

'  3.  In  moderate  quantities  it  has  no  appreciable  effect  on  the  blood-pressure. 
When  a  change  in  this  becomes  evident  it  is  always  in  the  direction  of  a  fall. 

'4.  By  virtue  of  its  local  action  on  mucous  membranes  and  on  the  brain, 
alcohol  is  capable  of  affecting  the  several  parts  of  the  vascular  apparatus  in  such 
ways  that  the  terra  "circulatory  stimulant"  may  be  applicable.  The  most 
frequent  of  these  indirect  effects  is  a  quickening  or  slowing  of  the  pulse-rate. 
Such  indirect  influences  must  not  be  allowed  to  hide  the  true  character  of 
alcohol,  which  is  always  depressant  in  kind. ' 

^  This  only  seems  to  occur  in  appreciable  degree,  however,  when  the  alcohol 
Is  taken  in  intoxicating  doses.  On  this  point  Atwater  and  Benedict  remark : 
•The  theory  that  the  energy  yielded  by  alcohol  is  lost  by  the  increased  heat- 
radiation,  like  the  theories  that  alcohol  is  not  oxidized  in  the  body,  and  that 
it  prevents  normal  oxidation  of  other  material,  was  suggested  by  observed  facts. 
In  each  case  the  facts  were  suggestive,  but  not  conclusive.  Under  crucial 
tests  they  are  found  to  fail '  ('  Physiological  Aspects  of  the  Liquor  Problem,' 
u.  297). 


344  FOOD  AND  DIETETICS 

usually  met  with  that  fate  through  their  having  been  in  a  state  of 
intoxication  when  the  cold  overtook  them. 

On  the  other  hand,  if  one  has  been  already  exposed  to  cold,  and 
the  blood  has  been  driven  into  the  internal  viscera,  and  is  stagnating 
there  and  about  to  produce  congestion,  the  timely  administration  of 
alcohol  may  save  the  situation  by  once  more  bringing  about  a  proper 
distribution  of  the  blood.*  By  all  means,  then,  take  alcohol  on 
coming  indoors  when  wet  or  chilled,  but  carefully  avoid  it  when 
about  to  proceed  out  to  meet  the  frost  or  rain. 

There  can  be  no  doubt  that  prolonged  over-indulgence  in  alcohol 
may  cause  the  vascular  paralysis  of  which  we  have  spoken  to 
become  permanent,  whence  the  bloated  look  and  purple  nose  of  the 
drunkard.  In  such  a  case  the  beneficial  eSects  which  should  other- 
wise be  obtained  from  the  administration  of  alcohol  in  acute  disease 
are  no  longer  manifested.  The  heart  and  bloodvessels  have  been  so 
often  stimulated  that  they  have  ceased  to  respond  to  the  spur,  and 
the  patient  often  pays  the  penalty  with  his  life. 

Influence  of  Alcohol  on  Metabolism. 

Alcohol  is  a  protoplasm  poison  or  ano'sthetic,  but  is  itself  easily  burnt  up 
in  the  body.  That  is  the  key  to  the  proper  understanding  of  its 
action  on  metabolism.  Let  us  see  more  exactly  what  the  statement 
means.  We  have  already  seen  (p.  22)  that  the  cells  of  the  body 
may  be  regarded  as  being  bathed  in  fluid  which  contains  in  solution 
particles  of  protein,  of  carbohydrate,  and  of  fat,  and  we  have  further 
learnt  that  there  is  reason  to  believe  that  these  are  broken  down  by 
the  cells  with  different  degrees  of  facility,  protein  being  most  easily 
destroyed,  then  carbohydrate,  and  lastly  fat.  If  now  alcohol  gets 
access  to  the  cell  and  partially  paralyzes  or  anaesthetizes  it,  the  cell 
will  lose  its  power  of  breaking  down  those  compounds,  such  as  fat, 
with  which  it  has,  even  in  a  condition  of  full  activity,  most  difficulty 
in  coping.  Alcohol,  then,  saves  fat  from  combustion  ;  in  other 
words,  it  is  a  fat-sparer.  It  also  appears,  though  with  greater 
difficulty,  to  be  able  to  spare  carbohydrate,  but  it  is  exceedingly 
doubtful  whether  it  is  ever  able  so  far  to  paralyze  the  cell  as  to 
destroy  its  power  of  dealing  with  protein.  This  action  of  alcohol  on 
cellular  activity  is  quite  in  keeping  with  what  we  know  of  the  effects 
of  other  cell  poisons.  Arsenic,  for  instance,  seems  to  impair  the  fat- 
destroying  power  of  the  cells,  while  there  is  some  reason  to  suppose 
that  lead  interferes  with  their  ability  to  break  down  protein,  and  so 

^  See  also  Brunton,  '  The  Physiological  Action  ef  Alcohol,'  Pructttiontr, 
1S76,  xvi    57,  iiS. 


ALCOHOL  AS  A  FOOD  345 

may  predispose  to  gout,  while  hydrocyanic  acid  is  the  most  powerful 
protoplasm  poison  known,  and  by  paralyzing  the  activity  of  the  cells 
in  every  direction  at  once  leads  to  death. 

Alcohol,  then,  certainly  spares  fat  and  sometimes  carbohydrate, 
but  in  so  doing  it  is  itself  consumed,  and  yields  heat  and  energy  to 
the  body.  Of  this  fact,  once  much  disputed,  there  is  no  longer  any 
doubt,  and  it  at  once  entitles  alcohol  to  rank  as  a  food.^  Careful 
experiments  have  shown  that  the  complete  combustion  of  i  gramme 
of  alcohol  in  the  body  yields  7  Calories  of  energy  ;  in  other  words, 
131  grammes  of  alcohol  will  yield  as  much  heat  as  100  grammes  of 
fat,  which  means  that  i  ounce  of  alcohol  supplies  as  much  fuel  as 
I  ounce  of  butter '  (about  200  Calories). 

This  statement  must  not  be  misunderstood.  It  does  not  follow 
from  it  that  alcohol  is  as  good  a  source  of  heat  in  the  food  as  fat. 
Quite  the  contrary  is  the  case,  for,  as  we  have  already  seen,  by 
dilating  the  surface  bloodvessels,  alcohol  may  cause  more  heat  to  be 
lost  than  it  is  itself  capable  of  producing.  Further,  alcohol  is  rapidly 
burnt  up,  and  the  heat  which  it  yields  is  quickly  dissipated,  while 
fat  produces  heat  in  a  slower  and  more  equable  fashion.  In  large 
doses  the  general  paralysis  of  cellular  activity  which  alcohol 
produces  is  so  great  that  heat  production  is  diminished  at  the  same 
time  as  heat  loss  is  increased,  and  the  final  result  is  a  great  lowering 
of  the  body  temperature,  which  may  even  amount  to  15°  F. 

There  is  still  less  reason  to  regard  alcohol  as  a  useful  muscle  food. 
Even  granting  that  it  can  be  oxidized  in  the  muscles  in  such  a  way 
as  to  be  capable  of  yielding  energy,  any  value  which  it  may  possess 
in  virtue  of  that  is  seriously  counterbalanced  by  the  paralyzing  effect 
which  it  exerts  on  nerve  cells,  dulling  the  sense  of  exhaustion  which 
is  Nature's  warning,  so  that,  as  experience  has  shown,  the  con- 
sumption of  alcohol  during  muscular  work  tends  to  hasten  rather 
than  delay  the  onset  of  fatigue.^ 

Seeing  that  alcohol  in  sparing  fat  and  carbohydrate  is  itself 
oxidized,  one  is  not  surprised  to  learn  that  its  administration  does 

*  80  per  cent,  of  fat. 

2  See  Scarborough,  '  Alcohol  as  a  Food,'  YahMed.Journ.,  January,  1910,  p.  239. 

'  See  ergographic  experiments  by  Destree,  Quarterly  Journal  of  Inebriety, 
January,  1S99  ;  also  Schnyder,  Pfluger's  Archiv,,  1903,  xciii.  451.  Later  observa- 
tions by  Rivers  ('Influence  of  Alcohol,  etc.,  on  Fatigue';  Edward  Arnold,  1908) 
show  that  in  doses  of  5  to  20  c.c.  of  pure  alcohol  there  is  no  effect  on  muscular 
fatigue  ;  with  doses  of  40  c.c.  the  results  are  inconstant.  On  the  whole,  alcohol 
seems  to  have  a  depressing  effect  on  mental  work,  and  a  stimulating  one  on 
muscular  work.  The  consensus  of  opinion  among  Alpine  climbers  ('  Alcohol  and 
Alpinism,'  by  Dr.  L.  Schnyder,  translated  by  E.  J.  Richards;  Edinburgh  and 
London  :  William  Green  and  Sons,  1910)  is  that  alcohol  should  be  avoided 
during  muscular  exertion,  although  it  is  believed  by  many  to  have  a  restorative 
effect  after  the  work  is  over. 


346  FOOD  AND  DIETETICS 

not  increase  or  diminish  either  the  intake  of  oxygen  or  the  output  of 
carbonic  acid  gas.i  On  the  other  hand,  if  the  amount  of  fat  or 
carbohydrate  in  the  diet  is  aheady  insufficient  for  the  needs  of  the 
body,  alcohol  is  able  to  supplement  them  by  acting  as  a  source  of  heat. 
Atwater  found  that  from  one-fifth  to  one-seventh  of  the  total  Calories 
of  the  diet  could  be  thus  replaced  by  alcohol,  and  this  explains  the 
observation  of  Hammond,  that  when  he  added  alcohol  to  a  diet  on 
which  he  was  losing  weight  the  loss  was  immediately  stopped.^ 

Anstie^  has  recorded  some  striking  instances  of  a  similar  sort  in 
which  alcohol  seemed  to  act  as  a  true  food.  He  kept  patients  alive 
during  acute  illness  for  many  days  on  nothing  but  large  quantities  of 
brandy,  and  found  that  they  had  not  emaciated  during  that  time 
nearly  so  much  as  they  would  have  done  if  they  had  been  merely 
living  on  their  own  tissues.  Nor  is  this  surprising,  for  the  amount 
of  alcohol  (12  ounces  of  brandy)  suppHed  daily  was  capable  of  yield- 
ing close  upon  1,000  Calories  to  the  body. 

Much  discussion  has  taken  place  amongst  physiologists  as  to 
whether  alcohol  is  or  is  not  a  protein-sparer.  It  would  be  impossible 
to  summarize  the  evidence  on  each  side  of  the  question  here,*  but  it 
may  be  stated  in  brief  that  the  results  of  the  latest  and  most  trust- 
worthy experiments  tend  to  show  that  alcohol  undoubtedly  possesses 
a  limited  power  of  lessening  nitrogenous  waste.  Its  influence  in  this 
respect,  however,  is  far  less  than  that  of  carbohydrates,  and  less  even 
than  that  of  fats,  and  seems  to  vary  under  the  influence  of  condi- 
tions which  are  not  fully  understood,  and  to  depend  also,  to  some 
extent,  upon  the  personal  peculiarities  of  the  subject  of  experiment. 
The  point  is  of  some  importance,  for  it  has  been  believed  by  many 
that  the  administration  of  alcohol  has  the  power  of  checking  the 
rapid  waste  of  nitrogenous  tissue  which  goes  on  in  fever.  Unless, 
however,  the  action  of  alcohol  is  very  different  in  fever  from  its 
behaviour  under  healthy  conditions — a  proposition  for  which  there 
is  no  real  e^^dence — one  is  not  justified  in  assuming  that  it  has  any 
appreciable  influence  in  that  direction. 

As  regards  the  general  influence,  then,  of  alcohol  on  metabolism, 
we  may  safely  conclude  (i)  that  it  is  burnt  up  in  the  body,  sparing 

^  Zuntz,  Fortschr.  d.  Med,,  1887,  v.  i,  and  Geppert,  Arck.  /.  Exper.  Path.  u. 
Pharmak.,  1S87,  xxii.  367. 

"  '  Physiological  Memoirs,'  1863,  p.  47. 

'  '  Stimulants  and  Narcotics,'  London,  1864. 

*  For  a  full  discussion  of  the  subject  see  '  An  Experimental  Inquiry  regarding 
the  Nutritive  Action  of  Alcohol,'  by  Atwater  and  Benedict  {Nat.  Acad.  0/  Sciences, 
1902,  vol.  viii. ,  Memoir  6);  also  Neumann,  Arck.  f.  Hygiene,  1902,  xli.  S5  ; 
Kassowitz,  Pfluger's  Archiv,,  1902,  xc.  421  ;  and  Goddard,  Lancet,  1904,  ii.  1132, 
1162. 

*  Rosenfeld,  however,  finds  (Abst.  in  Maly's  Jahres-Bericht  Thier-Chemie,  xxxvi. 
674)  that  alcohol  has  no  injurious  effect  on  metabolism,  and  is  a  better  protein, 
sparer  than  an  equal  quantity  of  sugar. 


ALCOHOL  AS  A   PROTOPLASM  POISON  347 

fat  and  carbohydrate  in  the  process,  but  that  (2)  the  weio;ht  of 
evidence  is  against  the  view  that  it  has  any  important  power  of 
diminishing  nitrogenous  waste. 

The  question  next  arises,  At  what  rate  does  the  combustion  of 
alcohol  in  the  body  go  on  ?  Is  it  so  rapid  that  all  of  it  is  decom- 
posed, or  is  there  time  for  some  of  it  to  be  eliminated  unchanged  ? 
The  reply  to  these  questions  is  that  much  depends  on  the  quantity 
of  alcohol  taken.  In  non-intoxicating  doses,  exceedingly  little,  not 
more  than  from  i  to  3  per  cent,  at  most,  passes  off  from  the  body 
unchanged.^  If,  on  the  other  hand,  the  quantity  consumed  be 
sufficient  to  produce  intoxication,  the  amount  of  alcohol  which 
escapes  combustion  may  rise  to  more  than  10  per  cent,  of  the  whole 
dose. 

Whenever  the  proportion  of  alcohol  circulating  in  the  blood 
becomes  greater  than  the  cells  can  rapidly  decompose,  its  effects  as 
a  protoplasm  poison  become  manifest.  In  their  extreme  form  those 
effects  culminate  in  intoxication,  which  is  really  a  condition  of  cell 
paralysis,  so  that  the  expression  *  paralytic  drunk '  has  a  truer 
physiological  meaning  than  those  who  use  it  commonly  suppose. 
The  brain  cells  seem  to  be  peculiarly  sensitive  to  the  paralyzing 
action  of  alcohol,  so  that  the  brain  is  the  first  to  show  the  effects  of 
an  overdose.  It  is  paralyzed  from  above  downwards,  the  higher 
centres  being  affected  first.  Now,  the  highest  centres  are  the 
controlling  centres  of  the  brain,  and  hence  loss  of  coijtrol,  intel- 
lectual, emotional  and  muscular,  is  the  earliest  sign  of  alcoholic 
intoxication.  It  is  only  in  the  extreme  degrees  of  the  condition  that 
the  *  driving  centres '  of  the  brain,  the  centres  of  organic  life  which 
maintain  the  action  of  the  heart  and  provide  for  respiration,  become 
involved  in  the  paralysis,  and  the  condition  then  is  one  not  merely 
of  intoxication,  but  of  coma,  and  threatens  life  itself. 

The  bad  effects  of  alcohol  taken  in  quantities  sufficient  to  produce 
intoxication  are  too  apparent  to  require  to  be  insisted  upon.  It 
must  be  remembered,  however,  that  the  habitual  consumption  of 
alcohol  in  quantities  which,  though  insuf.'^cient  to  produce  any  of  the 
outward  and  visible  signs  of  intoxication,  are  yet  beyond  the 
immediate  oxidizing  power  of  the  cells,  may  end  by  playing  havoc 
with  the  tissues.  Here,  again,  the  brain  seems  specially  liable  to 
suffer,  probably  owing  to  its  being  one  of  th3  most  highly  organized 
and  delicate  tissues  in  the  body.     As  the  result  of  chronic  alcoholism 

^  See  Anstie,  '  Final  Experiments  on  the  Elimination  of  Alcohol  from  the 
'Body,'  Practitioner,  1874,  xiii.  15.  See  also  Binz's  'Lectures  on  Pharmacology,' 
and  At  water  and  Benedict,  he.  cit.,  and  Goddard,  he.  cit. 


348  FOOD  AND  DIETETICS 

it  becomes  the  seat  of  various  degenerative  changes  to  which  the 
motor  centres  seem  less  resistant  than  the  sensory.  I  think,  too, 
that  one  can  recognise  in  the  habitual  alcoholic  a  certain  degree  of 
paralysis  of  the  moral  perceptions,  and  in  special  a  loss  of  the  sense 
of  truth.  Throughout  the  body  generally  the  presence  of  even  a 
slight  amount  of  undecomposed  alcohol  leads  to  a  diminution  of  the 
chemical  energy  of  the  cells,  which  interferes  with  the  ordinary  course 
of  metabolism,  and  may  result  in  chronic  disease.  The  metabolism 
of  fat  is,  for  reasons  already  pointed  out,  most  apt  to  be  interrupted, 
and  hence  alcoholism  is  a  common  cause  of  fatty  degenerations  and 
an  important  factor  in  many  cases  of  obesity.  By  delaying  the 
decomposition  of  carbohydrates,  it  aids  in  the  productions  of  some 
forms  of  diabetes,  and  there  can  be  no  doubt  that  it  plays  a  large 
part  in  that  alteration  of  protein  metabolism  which  seems  to  be  the 
basis  of  gout.^ 

It  seems  reasonable,  also,  to  suppose  that  the  excretion  by  the 
kidney  and  other  organs  of  undecomposed  alcohol  may  act  as  an 
irritant  and  bring  about  changes  in  structure,  which  may  end  in 
serious  interference  with  the  discharge  by  the  aflfected  organ  of  its 
normal  functions.  It  is  in  this  way,  for  example,  that  the  habitual 
consumption  of  more  alcohol  than  can  be  decomposed  in  the  body 
may  produce  chronic  nephritis.  All  these  considerations  bring 
home  to  one  the  very  great  importance  of  ascertaining,  if  only 
approximately,  how  much  alcohol  can  be  so  completely  oxidized  in 
the  body  that  there  will  be  none  left  over  to  exercise  upon  the  tissues 
those  injurious  influences  of  which  we  have  just  been  speaking. 
Experiments  carried  out  with  a  view  of  determining  this  point  have 
shown  that  i  to  i^  fluid  ounces  of  absolute  alcohol  is  about  the 
amount  which  can  be  completely  oxidized  in  the  body  in  one  day, 
and  in  such  a  way  that  none  of  its  paralyzing  or  narcotic  effects  are 
manifested,  and  no  unchanged  alcohol  appears  in  the  urine  (Parkes).^ 
This  quantity  of  alcohol  would  be  contained  in  the  following 
amounts  of  some  of  the  commoner  alcoholic  drinks : 

Brandy  or  whisky  (50  per  cent,  alcohol) 
Port,   sherry,    and    other   strong   wines 

{20  per  cent,  alcohol)   . . 
Claret,    hock,    champagne,    and    other 

weaker  wines  (10  per  cent,  alcohol)  .. 
Bottled  beer  (5  per  cent,  alcohol) 

^  See  also  Von  Strimipell,  '  Ueber  die  Alkohol  Frage  vora  Aerztlichen  Stand- 
punkt,'  aus  65ten  Versamml.  deut.  Naturforscher  zu  Niirnberg.  1893,  p.  97, 

*  Goddard  {loc.  cit.)  found  that  if  alcohol  was  administered  to  dogs  to  the 
extent  of  7-^  of  the  body  weight  it  was  almost  completely  oxidized.  If  the  same 
proportion  holds  good  in  the  human  subject,  a  man  of  average  weight  (150  pounds) 
ought  to  be  able  to  oxidize  about  3  ounces. 


2  fluid  ounces. 

or  I  glass. 

5       M              M 

or  2j  glasses. 

10        M               t* 

=  1  tumblerful. 

20        .. 

=  1  imperial  pint. 

ALCOHOL  IN  HEALTH  349 

Whilst  we  may  admit  the  probable  accuracy  of  the  data  on  which 
these  calculations  are  founded,  two  modifying  factors  have  to  be  con- 
sidered. The  first  of  these  is  the  question  of  idiosyncrasy.  There 
can  be  no  doubt  that  personal  peculiarity  plays  a  very  large  part  in 
determining  the  amount  of  alcohol  which  can  be  consumed  by  any 
given  individual  without  injury  to  health.  Some  persons  seem  to 
be  able  to  burn  up  alcohol  more  rapidly  and  completely  than  others, 
for  reasons  which  do  not  seem  to  be  connected  with  any  determinable 
peculiarity  of  physical  organization.  Certainly  every  one  must  have 
known  persons  who  were  able  to  go  on  consuming  daily  a  far  larger 
quantity  of  alcohol  than  the  standard  above  laid  down,  and  yet  with- 
out their  health  being  appreciably  impaired  by  the  indulgence. 
Indeed,  when  one  recalls  the  drinking  exploits  of  our  grandfathers 
and  the  prowess  of  the  '  three-bottle  men,'  one  is  almost  tempted  to 
think  that  the  power  of  our  tissues  to  oxidize  alcohol  has  actually 
undergone  a  decHne.  Apart  from  mere  peculiarities  of  constitution, 
it  must  be  obvious  that  the  surroundings  and  habits  of  each 
individual  must  afifect  very  greatly  the  amount  of  alcohol  in  which 
he  can  indulge  with  safety.  The  rapid  oxidation  which  is  the  result 
of  an  active,  open-air  life,  for  example,  enables  an  amount  of  alcohol 
to  be  consumed  with  impunity  which  would  work  disastrous  con- 
sequences in  one  of  sedentary  pursuits. 

The  other  factor  which  must  influence  any  calculation  as  to  the 
amount  of  alcohol  which  can  safely  be  consumed  daily  is  the  form 
and  mode  in  which  the  alcohol  is  taken.  It  will  be  generally  con- 
ceded that  the  same  quantity  of  alcohol  is  less  likely  to  be  injurious 
if  taken  in  a  dilute  than  in  a  concentrated  form.  It  must  be  evident 
also  that  an  amount  of  alcohol  which  would  be  harmful  if  swallowed 
at  one  time  may  be  free  from  risk  if  spread  evenly  over  the  day. 
The  danger  to  be  avoided  is  flooding  the  circulation  at  one  time  with 
an  amount  which  it  is  beyond  the  power  of  the  cells  to  oxidize. 

Use  of  Alcohol  in  Health. 

We  have  seen  that  one  cannot  deny  to  alcohol  the  right  to  be 
regarded  as  a  '  food '  in  the  scientific  sense  of  the  term.  We  have 
also  seen,  however,  that  it  cannot  be  regarded  as  a  food  of  any  great 
practical  importance,  for  it  is  merely  able  to  replace  a  certain 
amount  of  fat,  and  perhaps  also  of  carbohydrate,  in  the  body,  while 
its  secondary  effects  on  the  nervous  and  vascular  systems  counteract, 
to  a  large  extent,  the  benefits  derived  from  the  production  of  heat 
and  energy  by  its  oxidation.     As  a  food,  also,  alcohol  is  open  to  the 


350  FOOD  AND  DIETETICS 

additional  objection  of  being  very  costly.  Even  in  Bavaria,  the 
land  of  cheap  beer,  it  has  been  calculated  that  alcohol,  in  that,  its 
least  expensive  form,  is  eight  times  dearer  than  bread,  from  the 
point  of  view  of  the  amount  of  heat  yielded. 

It  has  been  shown  that  alcohol  is  not  favourable  to  the  production 
of  sustained  muscular  effort,  and  that  it  may  even  do  harm  by 
paralyzing  the  sense  of  fatigue  which  is  the  natural  check  on  exces- 
sive exertion.  Nor  can  it  be  said  that  it  is  favourable  to  the  produc- 
tion of  perfectly  healthy  brain-work.  An  interesting  book^  was 
published  a  few  years  ago  in  which  were  gathered  together  the 
results  of  the  personal  experience  of  leading  men  in  literature,  science 
and  art  on  the  effects  of  stimulants  as  aids  to  intellectual  work.  It 
is  interesting  to  note  that,  out  of  the  124  individuals  consulted,  none 
ventured  seriously  to  recommend  alcohol  as  an  aid  in  the  performance 
of  mental  labour.  As  Abel  has  said  :^  '  He  who  has  mental  labour 
of  an  exacting  kind  to  perform  and  he  upon  whom  great  responsi- 
bilities devolve,  is  forced,  if  he  would  be  at  his  best,  to  use  alcohol 
as  a  restorative  agent  only  at  the  proper  season  ;  he  must  behave 
to  it  as  he  does  to  many  other  pleasures  and  luxuries  in  his  environ- 
ment.'    A  census  in  America  yielded  much  the  same  result.^ 

We  may  conclude,  then,  that  alcohol  is  an  unnecessary  article  of 
diet  in  complete  health,  although,  if  used  within  the  limits  already 
indicated,  it  cannot  be  said  to  be  harmful,  and  may  even,  indeed,  be 
beneficial ;  for,  as  Matthew  Arnold  has  said  in  the  book  already 
referred  to,  *  wine  used  in  moderation  seems  to  add  to  the  agreeableness 
of  life — for  adults,  at  any  rate — and  whatever  adds  to  the  agreeable- 
ness of  life  adds  to  its  resources  and  power.' 

It  is  in  conditions  just  short  of  health,  however — in  old  age,  over- 
work and  fatigue — that  the  beneficial  effects  of  alcohol  become  most 
marked.  They  may  be  traced  almost  entirely  to  its  favourable 
influence  on  digestion,  and  hence  a  good  rule  for  the  use  of  alcohol 
in  all  conditions  short  of  actual  disease  is  to  take  it  only  at  meals, 
and  in  such  quantities  as  are  found  to  improve  the  appetite  for  food 
and  the  capacity  for  digesting  it.  As  regards  the  form  in  which  it 
should  be  used,  beer  seems  most  natural  for  youth,  wine  in  middle 
life,  whilst  spirits  may  be  reserved  for  the  aged.  * 

1   '  Study  and  Stimulants,'  A.  A.  Reade  (Simpkin,  Marshall  and  Co.,  1883). 

"  '  Physiological  Aspects  of  the  Liquor  Problem,'  ii.  165. 

'  Ibid.,  vol.  i. 

*  In  the  Contort porary  Review  for  187S  and  1879  there  will  be  found  a  very 
interesting  discussion  of  the  alcohol  question,  in  which  several  distinguished 
physicians  and  surgeons  took  part.  The  opinion  of  most  of  them  was  that  the 
moderate  use  of  alcohol  in  health  is  harmless,  if  not  indeed  actually  beneficial. 


ALCOHOL  IN  DISEASE  351 

Use  of  Alcohol  in  Disease. 

Just  as  the  effect  of  alcohol  on  the  digestion  is  the  test  of  its  value 
in  health,  so  its  effects  on  the  circulation  and  nervous  system  are 
the  criterion  of  its  usefulness  in  most  cases  of  acute  disease.  As 
long  as  the  efficiency  of  the  heart  is  improved  by  its  administration, 
alcohol  is  doing  good.  In  fever,  its  power  of  lowering  temperature 
and  its  calming  influence  on  the  brain  are  also  of  use,  while  it 
may,  perhaps,  check  somewhat  the  tissue  waste  which  is  so  marked 
a  feature  of  acute  fevers,  although  we  have  seen  reason  to  doubt 
this — at  least,  as  far  as  the  nitrogenous  tissues  are  concerned.  To 
this  point,  however,  we  shall  return  in  another  chapter  (p.  484). 
There  are  grounds  also  for  the  belief  that  alcohol  actually  increases 
the  resisting  power  of  the  body  to  the  poisons  of  certain  diseases — 
such,  for  example,  as  septic  fevers.  I  am  aware  that  laboratory 
experiments^  have  shown  that  rabbits  in  a  state  of  intoxication  are 
actually  less  resistant  than  normal  to  certain  organisms,  such  as  the 
streptococcus  of  erysipelas,  but  the  dose  of  alcohol  administered  was 
excessive ;    and  to  set  against   these  results  we  have   the  clinical 

In  Dr.  Wilks'  paper  the  view  that  alcohol  is  essentially  a  narcotic  rather  than  a 
stimulant  is  strongly  presented,  while  Dr.  Moxon  deals  in  the  most  interesting 
manner  with  its  effects  on  the  mental  faculties.  The  conclusions  of  Dr.  Murchi- 
son,  which  are  not,  however,  in  complete  harmony  with  those  of  most  of  the 
other  contributors,  are  as  follows : 

1.  A  man  in  good  health  does  not  require  alcohol,  and  is  probably  better  with- 
out it.  Its  occasional  use  will  do  him  no  harm  ;  its  habitual  use,  even  in 
moderation,  may,  and  often  does,  induce  disease  gradually. 

2.  There  are  a  large  number  of  persons  in  modern  society  to  whom  alcohol, 
even  in  moderate  quantity,  is  a  positive  poison. 

3.  In  all  conditions  of  the  system  characterized  by  weakness  of  the  circulation, 
the  daily  use  of  a  small  quantity  of  alcohol  is  likely  to  be  beneficial,  at  all  events 
for  a  time. 

Sir  James  Paget  wrote  :  '  I  cannot  doubt,  with  such  evidence  as  we  have,  that 
the  habitual  moderate  use  of  alcoholic  drink  is  generally  beneficial,  and  that 
in  the  question  raised  between  temperance  and  abstinence  the  verdict  should  be 
in  favour  of  temperance. ' 

On  the  whole,  the  views  presented  by  these  writers  may  be  regarded  as  fairly 
representing  contemporary  medical  opinion  on  the  subject. 

1  See  Abbott,  Journal  of  Experimental  Medicine,  1896,  i.  447.  Parkinson  {Lancet, 
1909,  ii.  1580),  as  a  result  of  experiments  on  the  relation  of  alcohol  to  immunity, 
arrives  at  the  following  conclusions  : 

1.  Alcohol  in  small  quantities  has  no  action  upon  the  phagocytic  activity. 

2.  It  has  no  action  on  the  phagocytic  activity  until  it  is  present  in  i2'5  per 
cent,  strength. 

3.  Small  quantities  of  alcohol  injected  into  rabbits  may  stimulate  the  produc- 
tion of  antibodies  temporarily. 

4.  A  large  dose  of  alcohol  lowers  the  opsonic  index  for  twenty-four  hours. 

5.  Continuous  moderate  doses  of  alcohol  cause  a  permanent  lowering  of  the 
opsonic  index. 

6.  The  reacting  mechanism  to  vaccines  is  much  less  effective  in  alcoholized 
rabbits  than  in  normal  rabbits ;  the  difference  is  still  more  marked  when  living 
micro-organisms  are  used. 


35a  FOOD  AND  DIETETICS 

experience  of  good  observers,  who  regard  alcohol  as  being  actually 
an  antidote  to  acute  erysipelas. 

In  some  chronic  diseases,  such  as  diabetes,  alcohol  is  used  as  a 
real  food  to  replace  a  certain  amount  of  carbohydrate  in  the  diet, 
whilst  in  others  it  is  chiefly  its  tonic  influences  on  digestion  which 
one  seeks  to  obtain.  We  shall  have  occasion  to  study  its  uses  in 
these  different  directions  in  detail  in  subsequent  chapters. 


£353  J 


CHAPTER  XX 

ALCOHOLIC  BEVERAGES  :  SPIRITS  AND  MALT  LIQUORS 

Before  proceeding  to  the  study  of  the  alcoholic  beverages  in  detail, 
it  may  be  well  to  describe  the  different  ways  in  which  the  amount  of 
alcohol  which  they  contain  may  be  stated.  This  is  all  the  more 
important  as  an  inaccurate  use  of  terms  may  lead  to  some  confusion. 

In  this  country  the  standard  employed  is  usually  what  is  known 
as  proof  spirit,  and  an  alcoholic  liquor  is  said  to  be  so  much  above 
or  so  much  under  '  proof.'  Proof  spirit  is  a  mixture  of  alcohol  and 
water,  which  contains  49*24  per  cent,  of  the  former  hy  weight  {i.e., 
100  grammes  contains  49*24  grammes  alcohoU),  and  57"o5  per  cent, 
by  volume  {i.e.,  100  c.c.  contains  57*06  c.c.  alcohol).  'The  name 
proof  spirit  owes  its  origin  to  the  practice  in  vogue  during  last  century, 
of  testing  the  strength  of  samples  of  alcohol  by  pouring  them  on  to 
gunpowder  and  applying  a  light.  If  the  sample  contained  much 
water  the  alcohol  burned  away,  and  the  water  made  the  powder  so 
damp  that  it  did  not  ignite  ;  but  if  the  spirit  were  strong  enough  the 
powder  took  fire.  A  sample  which  just  succeeded  in  igniting  the 
powder  was  called  proof  spirit  *  (Perkins  and  Kipping).  Spirits  are 
described  as  being  over  proof  when  they  are  stronger  than  proof  spirit, 
and  under  proof  when  they  are  weaker.  Thus,  20  over  proof  means 
that  100  volumes  of  the  spirit  contain  as  much  alcohol  as  120  of 
proof  spirit,  and  20  under  proof  means  that  100  volumes  only  contain 
as  much  alcohol  as  80  of  proof  spirit. 

Instead  of  using  proof  spirit  as  the  standard,  it  is  more  convenient 

to  speak  of  the  amount  of  alcohol  as  being  so  much  per  cent.     The 

percentage  may  further  be  stated  either  in  weight  or  in  volume. 

Five  per  cent,  of  alcohol  by  weight  means,  strictly  speaking,  that 

100  grammes  of  the  liquid  in  question  contain  5  grammes  of  alcohol ; 

but  more  usually  the  expression   is   used   for   weight   in   volume — 

^  100  grammes  of  proof  spirit  has  a  volume  of  about  no  c.c,  for  shrinkage 
occurs  when  water  and  alcohol  are  mixed. 

23 


354  FOOD  AND  DIETETICS 

i.e.,  5  grammes  of  alcohol  in  loo  c.c.  Five  per  cent,  by  volume 
means  5  c.c.  in  every  hundred,  and  is  equivalent  to  about  4  percent, 
by  weight. 1  The  percentage  of  alcohol  by  volume  in  some  of  the 
commoner  alcoholic  beverages  is  roughly  as  follows  : 

Rum  . .  "j  Port           ..  25  per  cent.  Hock         ..    10  per  cent. 

Whisky  ..  >-43  per  cent.  Sherry       ..  21        ,,  Claret        ••     9        „ 

Brandy  ..J  Champagne  10  to  15  per  Bottled  beer    7        „ 

Gin  ••    37        M  cent.  Lager  beer       4        „ 


Spirits. 

Spirits  are  obtained  by  the  fermentation  of  various  saccharine 
substances,  the  alcohol  and  other  volatile  bodies  produced  being 
separated  by  distillation.  It  is  this  fact  of  their  being  the  products 
of  distillation  which  gives  to  spirits  their  high  alcoholic  strength, 
and  distinguishes  them  from  all  other  alcohol-containing  beverages. 
Almost  any  substance  capable  of  yielding  a  fermentable  sugar  may 
form  the  basis  of  fermentation.  Amongst  the  substances  most 
commonly  used  in  this  country  are  malted  and  unmalted  barley, 
maize,  rice,  sugar,  and  molasses.  In  some  parts  of  Europe,  and 
especially  in  Russia,  potato  starch  is  largely  employed  for  the 
purpose.  All  of  these  substances  yield  alcohol  on  fermentation,  but 
in  addition  various  bye-products  make  their  appearance  during  the 
process,  and  it  is  to  the  presence  of  these  that  the  characteristic 
flavour  of  the  different  spirits  is  due. 

Thus,  the  bye-products  of  the  fermentation  of  malted  barley  give 
rise  to  the  flavour  of  whisky,  those  of  molasses  to  the  flavour  of  rum, 
and  those  of  the  grape  to  that  of  brandy.  By  means  of  patent  stills 
the  bye-products  can  be  almost  entirely  separated  from  the  alcohol 
with  which  they  are  mixed,  and  the  result  is  an  almost  pure  form  of 
spirit,  the  origin  of  which  can  scarcely  be  told,  for  which  reason  it  is 
called  Sil.nt  spirit.  By  suitable  flavouring  the  artful  manufacturer 
can  make  this  the  basis  of  almost  any  spirituous  drink. 

Amongst  the  bye-products  of  fermentation  there  are  usually  found 
alcohols  which  are  higher  homologues  of  ethyl  alcohol — e.g.,  propyl, 
butyl,  and  amyl,  and  to  a  mixture  of  these  the  term  fusel-oil  is  often 
applied.  There  is  some  reason  to  beheve  that  fusel-oil  is  the 
product  of  a  later  fermentation  which  takes  place  after  the  alcoholic 
fermentation  is  completed,  and  it  appears  to  be  produced  in  larger 
quantity  at  high  temperatures  than  at  low.  We  shall  see  imme- 
diately that  fusel-oil  and  the  other  bye-products  met  with  in  spirits 

1  c.c.  alcohol  in  100  vols,  x  08  =  grammes  in  100  vols. 
Grammes  alcohol  in  100  vols,  x  1-25  =  0. c.  in  100  vols. 

„  „       in  I  litre  X  7  =  grains  per  gallon  (6  bottles). 


SPIRITS  355 

have   effects  on   the   body  in   health  and  disease  only  second   to 
that  of  the  ethyl  alcohol  itself. 


Whisky. 

Whisky  has  been  defined  by  the  Chairman  of  the  Inland 
Revenue  Board  as  'a  spirit  made  from  malt  or  malt  and  grain, 
and  distilled  in  pot-stills.'^  In  the  United  States  Pharmacopoeia 
it  is  described  thus :  '  A  spirit  obtained  from  fermented  grain  by 
distillation,  and  containing  from  48  to  56  per  cent,  by  volume  of 
alcohol.  It  should  be  free  from  disagreeable  odour,  and  not  less 
than  two  years  old.' 

It  is  important  to  distinguish  clearly  between  genuine  *  malt 
whisky,'  which  is  made  in  'pot-stills,'  and  '  grain  whisky,'  which  is  pre- 
pared in  '  patent  stills.'  The  bulk  of  ordinary  whisky  as  it  reaches 
the  consumer  is  probably  a  blend  of  these  two,  grain  whisky  usually 
predominating. 

(a)  Malt  whisky  is  prepared  from  malted  barley  which  is  first 
carefully  dried.  In  many  Highland  distilleries  peat  is  used  as  the 
fuel  for  drying,  and  some  of  the  characteristic  flavour  of  such  whisky 
is  believed  to  be  derived  from  the  peat  smoke.  After  being  dried, 
the  malt  is  made  into  a  mash,  and  here,  just  as  we  shall  see  is  true 
of  beer,  the  nature  of  the  water  used  seems  to  have  some  influence 
on  the  character  of  the  final  product,  soft  water  giving  the  best 
result.  The  mash  is  then  fermented  much  as  in  the  making  of  beer, 
only  the  process  is  allowed  to  go  on  longer.  When  fermentation  is 
complete,  the  fermented  mash  or  '  wash '  is  distilled  in  the  old- 
fashioned  pot-still.  This  is  the  form  of  still  which  is  by  far  the  most 
commonly  used  in  Scotch  and  Irish  distilleries.  It  is  made  of 
copper,  and  the  volatile  products  are  condensed  in  a  simple  '  worm,' 
no  attempt  being  made  to  separate  the  spirit  from  the  bye-products. 
The  still  is  heated  over  an  open  flame.  This  is  a  point  of  some 
importance,  for  it  causes  some  of  the  sugary  substances  in  the 
wash  to  become  slightly  charred,  and  there  is  produced  in  this 
way,  amongst  other  things,  the  substance  furfurol,  the  presence 
of  which  is  one  of  the  chief  distinguishing  characteristics  of  pot- 
still  whisky. 

The  first  product  of  the  distillation  is  called  low  wines.     These  are 

1  The  Royal  Commission  on  Whisky  and  Other  Potable  Spirits,  which  reported 
in  igog,  however,  concluded  that  the  term  '  Whisky  '  may  legitimately  be  applied 
to  the  product  of  a  patent  still  also. 


356  FOOD  AND  DIETETICS 

redistilled,  and  yield   (i)   '  fore-shots,' (2)  '  clean  spirit,'  or  whisky, 
(3)  '  feints ' ;  the  residue  left  in  the  still  being  the  *  spent  lees.' 

The  fore-shots  and  feints  both  contain  much  of  the  bye-products  of 
fermentation,  and  are  redistilled,  the  distillate  being  added  to  the 
clean  spirit,  or  whisky. 

It  must  be  noted  that  no  fusel-oil  is  obtained  separately  by  this 
method  of  distillation,  and  the  product  consists  of  alcohol  plus  some 
of  the  bye-products  of  fermentation.  The  whisky  thus  produced  has 
an  alcoholic  strength  of  from  13  degrees  to  50  degrees  over  proof,  but 
before  bonding  it  is  usually  reduced  in  Scotland  to  1 1  degrees  and 
in  Ireland  to  25  degrees  over  proof. 

The  bye-products  —  chiefly  aldehydes  —  which  it  contains  give 
it,  when  young,  a  raw,  harsh  and  disagreeable  taste,  but  after 
keeping  for  some  years  in  wood  it  mellows  greatly,  and  the  harsher 
the  taste  when  young,  the  more  full  flavoured  the  whisky  when 
matured. 

What  the  exact  nature  of  the  changes  is  by  which  the  improve- 
ment which  whisky  undergoes  in  wood  is  brought  about  we  do  not 
yet  fully  know.  This  we  do  know,  however,  that  the  percentage  of 
alcohol  diminishes,  6  to  8  per  cent,  of  proof  spirit  being  lost  by  five 
years'  storage.  On  the  other  hand,  the  fusel-oil  does  not  seem  to 
undergo  diminution,  in  spite  of  frequent  statements  to  the  contrary.^ 

Irish  pot-still  whisky  differs  from  Scotch  in  being  prepared  usually 
from  a  mixture  of  malted  barley  with  unmalted  grain  (barley  or 
maize),  and  the  malt  is  not  dried  over  peat.  Otherwise  the  manu- 
facture of  the  two  is  very  similar. 

(b)  Grain  Whisky. — This  is  the  form  of  whisky  most  commonly 
distilled  in  England.  It  is  made  from  a  mixture  of  grains  (barley, 
rye  and  maize),  with  just  a  sufficiency  of  malt  to  convert  their  starch 
into  sugar.  More  important  than  this  distinction,  however,  is  the 
fact  that  it  is  distilled  by  steam  and  in  a  patent  (Coffey's)  still  in 
such  a  way  that  the  bye-products  of  fermentation  (fusel-oil,  etc.) 
are,  to  a  large  extent,  separated  from  the  ethyl  alcohol.  The  result 
is  that  the  raw  product  has  much  less  flavour  than  young  malt 
whisky,  and  is  sooner  ready  to  go  into  consumption.  When  run  off 
the  still  it  is  almost  colourless  and  has  an  alcoholic  strength  of 
60  degrees  over  proof,  but  is  usually  diluted  to  11  to  12  degrees  ovei 
proof  before  bonding.  It  acquires  a  yellowish  colour  from  being 
stored  in  old  sherry-casks. 

^  See  Dr.  Bell's  evidence  before  the  Select  Committee  on  British  and  Foreign 
Spirits,  1890-91.  Allen,  however,  does  not  agree  with  this.  He  considers  that 
some  of  the  fusel-oil  is  converted  into  volatile  ethers. 


WHISKY  357 

As  regards  the  main  differences  between  the  two  varieties  of 
whisky,  1  would  emphasize — 

1.  That  patent-still  whisky  contains  much  less  of  the  bye-products 
of  fermentation  (including  fusel-oil)  than  pot-still  whisky,  and  is 
therefore  much  purer. 

2.  That  as  a  consequence  of  this  patent-still  whisky  does  not 
improve  nearly  so  much  on  keeping  as  the  other  variety. 

It  follows  from  this  that  a  young  patent-still  whisky  is  much 
better  to  drink  than  young  malt  whisky,  but  that  the  latter,  when 
fully  matured,  has  a  fuller  and  pleasanter  flavour  than  the  former. 
It  is  absurd  to  object  to  grain  whisky  on  the  ground  that  it  contains 
more  fusel-oil  than  malt  whisky,  for  just  the  reverse  is  the  truth. 
After  removal  from  bond,  whisky  is  diluted — or  '  broken  down,*  as  it 
is  termed  in  the  trade — by  the  addition  of  water.  The  legal  limit  of 
dilution  is  25  degrees  under  proof  (42-7  per  cent,  alcohol  by  volume), 
and  the  majority  of  vendors  may  be  trusted  to  take  full  advantage  of 
the  permission,  so  that  the  ordinary  whisky  sold  in  bottle  is  of  this 
strength ;  indeed,  of  fifty-one  samples  of  public-house  whisky  taken 
from  all  over  the  country,  the  strength  was  from  15  to  25  under 
proof  in  all  but  two  instances.^  In  other  words,  we  shall  not  go  far 
wrong  if  we  regard  a  glass  of  whisky  as  containing  rather  less  than 
half  a  glass  of  absolute  alcohol. 

As  already  mentioned,  most  commercial  whiskies  are  blends,  and 
not  the  product  of  one  distillery  at  all.  Grain  whisky  is  often  used 
as  the  basis  of  the  blend,  a  certain  proportion  of  malt  being  added 
10  give  flavour.  Even  when  the  blend  contains  as  much  as  90  per 
cent,  of  grain  whisky,  it  is  often  sold  as  '  genuine  malt.'^  The  public 
taste  at  present  is  certainly  in  favour  of  a  mild-flavoured  whisky, 
hence  the  large  use  of  grain  spirit  in  blends. 

Potheen  is  the  product  of  illicit  stills,  and,  being  usually  made 
from  molasses,  has  the  characteristics  of  rum  rather  than  those  of 
true  whisky. 

Brandy. 

If  whisky  be  regarded  as  distilled  beer,  brandy  may  be  spoken  of 
as  distilled  wine. 

1  Select  Committee's  report. 

2  There  can  be  no  question  that  such  a  practice  is  unfair  to  the  consumer,  for 
whatever  may  be  said  of  the  relative  merits  of  malt  and  grain  spirit,  everyone 
has  a  right  to  know  the  nature  of  the  whisky  he  is  buying.  It  would  be  well, 
therefore,  if  the  law  should  insist  that  the  character  and  origin  of  the  contained 
spirit  should  be  printed  upon  the  label  of  the  bottle.  (See  •  The  Practice  of 
Substitution  in  the  Spirit  Trade,'  Lancet,  1903,  i.  542.) 


358  FOOD  AND  DIETETICS 

The  best  brandy  was  originally  produced  in  one  of  the  richest 
wine  districts  of  France  (Departement  de  la  Charente  or  Cognac 
district).  The  quality  varies  with  the  character  of  the  grapes,  the 
best  grapes  yielding  the  variety  known  as  Fine  or  Grande 
Champagne.  This  is  the  only  genuine  liqueur  brandy.  The 
varieties  known  as  Petite  Champagne  and  Premi&re  Bois  rank 
next  to  it.  If  sold  pure,  these  constitute  old  Cognac,  but  a  large 
amount  of  them  is  used  for  blending  with  inferior  varieties. 

In  a  good  year  six  or  seven  bottles  of  wine  should  yield  one  bottle 
of  brandy.  When  first  distilled  the  spirit  is  devoid  of  colour  and  of 
a  fiery  character.  When  kept  in  cask  it  takes  up  colour  from  the 
^vood  and  gradually  becomes  mellower.  Improvement  goes  on  for 
a  long  time,  so  that  the  older  the  brandy  the  better.  After  twenty 
or  forty  years  it  contains  a  considerable  proportion  of  volatile  ethers 
and  aldehydes,  to  which  some  of  the  most  valuable  properties  of 
brandy  are  to  be  attributed.* 

While  the  above  is  the  origin  of  genuine  brandy,  it  must  be 
admitted  that  very  little  of  the  brandy  sold  in  this  country  is  so 
derived.  The  greater  part  of  it  is  really  concocted  in  the  Cognac 
district  from  *  silent  spirit '  coloured  with  burnt  sugar  and  flavoured 
with  oenanthine  or  various  essences.  Such  a  product  is  entirely 
different  from  genuine  brandy,  for  it  contains  but  little  of  those 
volatile  ethers  derived  from  wine  which  are  so  conspicuous  in 
genuine  Cognac,  and  to  which,  as  we  shall  see,  it  owes  most  of  the 
valuable  results  it  is  capable  of  producing  in  sickness. 

The  production  of  genuine  brandy  by  the  distillation  of  Spanish 
wines  has  recently  been  begun  at  Jerez  and  elsewhere,  and  the 
product  is  pronounced  by  competent  authority  to  be  fully  equal,  in 
regard  to  the  amount  of  ethers  present,  to  pure  Cognac.^  If  this 
standard  is  maintained,  Spanish  brandy  should  have  a  great  future. 
It  is  the  possession  of  volatile  ethers  in  large  amount  which  mainly 
distinguishes  brandy  from  whisky  ;  as  regards  alcoholic  strength,  the 
two  are  about  equal. 

Rum. 

Rum  is  usually  produced  by  the  distillation  of  fermented  molasses 
obtained  in  the  manufacture  of  raw  sugar  ;  the  best  varieties,  how- 

*  For  the  changes  which  take  place  in  brandy  by  age,  see  a  paper  by  Rocques 
(ref.  in  Analyst,  1897,  p.  38) ;  also  '  Report  of  the  Lancet  Special  Analytical  Com- 
mission on  Brandy '  (Supp.  to  the  Lancet,  1902,  ii.  1503). 

2  See  •  The  Composition  of  Brandy,"  by  Sir  Charles  Cameron  and  Professor 
W.  R.  Smith,  Journal  oj  State  Medicine,  1899,  vii.  317. 


GIN  359 

ever,  are  obtained  by  direct  fermentation  of  the  juice  of  the  sugar 
cane.  The  spirit  contains  bye-products  of  fermentation,  which 
impart  to  rum  its  characteristic  flavour.  The  chief  of  these  is 
said  to  be  ethyl  butyrate,  and  a  considerable  proportion  of  the  rum 
sold  in  this  country  is  made  from  silent  spirit  flavoured  with  that 
substance. 

Rum  owes  its  dark  colour  to  burnt  sugar.  When  kept  for  some 
time,  it  improves  greatly  in  flavour  by  the  development  of  ethers  in 
which  it  is  peculiarly  rich.  It  usually  goes  into  consumption  at 
about  the  same  alcoholic  strength  as  whisky,  or  perhaps  a  little 
stronger. 

Gin. 

Gin  (also  known  as  Geneva — from  genievre,  a  juniper — Schiedam 
and  Hollands)  is  obtained  by  fermenting  a  mash  of  rye  and  malt, 
and  distilling  and  redistilling  the  product.  Juniper-berries  and  a 
little  salt,  and  sometimes  also  hops,  are  added  in  the  final  distillation, 
and  the  product  is  run  off  into  underground  cisterns  lined  with  white 
tiles,  where  the  spirit  can  be  kept  without  colouring. 

The  chief  seat  of  the  manufacture  of  genuine  gin  is  at  Schiedam 
in  Holland.  Much  so-called  gin,  however,  is  fabricated  elsewhere 
out  of  silent  spirit  flavoured  with  salt,  juniper-berries,  and  turpentine. 

Gin  is  allowed  to  be  sold  with  as  low  a  proportion  of  alcohol  as 
35  under  proof  (37  per  cent,  alcohol  by  volume),  but  is  usually  im- 
ported at  14  to  15  under  proof.  It  is  thus  one  of  the  most  dilute  of 
spirituous  drinks.  Sweetened  and  diluted  gin  is  sold  under  the  name 
of  Old  Tom. 

Whilst  varying  somewhat  in  alcoholic  strength,  all  the  spirits  we 
have  been  considering  agree  in  containing  very  little  solid  matter — 
less,  indeed,  than  i  per  cent.,  gin  being  the  poorest  in  this  respect. 
They  have  also  a  very  low  degree  of  acidity,  rum  standing  highest, 
then  brandy,  with  i  grain  per  ounce  (reckoned  as  tartaric  acid), 
while  whisky  and  gin  have  only  about  0*2  grain  per  ounce.  They 
are  all  practically  free  from  sugar,  for  which  reason  the  introduction 
of  special  whiskies  for  diabetics  is  quite  unnecessary. 

The  following  table,  taken  from  the  Report  of  the  Lancet 
Special  Analytical  Commission  on  Brandy,  represents  the  com- 
parative composition  of  the  different  spirits  in  a  convenient 
form  : 


360 


FOOD  AND  DIETETICS 


Constituents. 

Grain 
Spirit. 

Beet 
Spirit. 

Jamaica 
Rum. 

Scotch 
Whibky. 

Gin. 

Typical 

3-Star 
Brandy. 

Alcohol  per  litre  by  weight 

932 '60 

912-90 

619-20 

436-20 

401-50 

410-50 

, ,              , ,      by  volume 

956-00 

942  00 

695  00 

512*00 

47500 

485  00 

Equal  to  proof  spirit  per 

cent. 

167-55 

165-09 

121-79 

89-77 

8326 

84-96 

Extract  per  litre  . . 

Nil. 

Nil. 

6-36 

I-I6 

052 

670 

Acidity      (calculated      as 

acetic  acid 

2*40 

4-80 

122-40 

33-60 

19-20 

3750 

Aldehydes      (as      ethylic 

aldehyde) 

115 

10-92 

15  41 

14-38 

4-72 

6'io 

Furfurol     . .          . .         , . 

Nil. 

Nil. 

2-08 

1-94 

0-I3 

0'82 

Alcohol  in  ethers  (not  in 

total)       

1-84 

9-20 

i6r-oo 

20-24 

460 

27-88 

Ethers  (expressed  as  ethyl 

acetate)   . . 

y5^ 

17-60 

308-00 

387^ 

880 

53-35 

Higher  alcohols    .. 

I'So 

6-95 

62-58 

122-76 

13-25 

58-48 

Liqueurs  and  Bitters. 

This  group  of  liquors  may  be  regarded  as  consisting  essentially 
of  spirit  sweetened  with  cane-sugar  and  flavoured  with  aromatic  or 
other  herbs  or  essences.  It  has  been  well  said  that  they  are  chiefly 
the  product  of  the  alchemist  and  the  monastery.  The  proportion  of 
alcohol  in  them  is  high,  varying  from  33  to  50  per  cent,  or  more  by 
volume.  The  proportion  of  the  other  ingredients  is  shown  in  the 
following  analyses  of  some  of  the  most  prominent  members  of  tlie 
group,  taken  from  Konig  : 


Ale 

ohol. 

Extract. 

Cane- 

Various 

Ash 

By  vol. 

By  weight. 

sugar. 

Extractivts. 

Absinthe    .. 

5S93 

— 

o-i8 

— 

032 

Benedictine 

52  00 

385 

36-00 

l'2-57 

3-43 

0  406 

Creme  de  Menthe 

48.00 

365 

28-28 

2763 

065 

0  043 

Anisette     . . 

42.00 

307 

3482 

3444 

038 

0  068 

Cura(;oa     . . 

5500 

42-5 

28-60 

2850 

Q-IO 

0040 

Kiimmel     . . 

33  90 

24-8 

3202 

31-18 

0-84 

0058 

Angostura . . 

49  70 

— 

5-85 

4-16 

I  69 

0068 

Chartreuse 

4318 

— 

36- 1 1 

3437 

1-76 

The  following  is  a  brief  description  of  the  origin  and  constituents 
of  some  of  the  better-known  liqueurs  and  bitters  :^ 

Absinthe. — Made  by  macerating  Alpine  plants  of  the  wormwood 
species  with  the  root  of  anise  and  sweet-flag  and  marjoram  leaves  in 
40  per  cent,  spirit.  A  glassful  (30  c.c.)  contains  the  following 
amounts  of  absolute  alcohol : 


1  For  this  description  the  author  is  largely  indebted  to  Simmonds'  '  Popular 
Beverages  of  Various  Countries,"  London,  1888. 


SPIRITS  361 

OHinary  absinthe     ..     14-30.0.      I      Fine 20-40,0. 

Demi-fine         ..  ..     150     .•       I       Suisse 24*2   „ 

The  essential  oil  of  wormwood  is  a  convulsive  poison. 

Curagoa. — Made  in  Amsterdam  from  the  rind  of  bitter  oranges 
grown  in  the  island  of  Cura9oa. 

Kirsch. — Made  from  cherries  in  the  Black  Forest. 

Noyau. — Made  from  the  stones  of  cherries,  containing  oil  of  bitter 
almonds. 

Maraschino. — Made  by  fermenting  a  small  sour  cherry  {marasca) 
grown  in  Italy  and  Dalmatia.  Both  the  cherries  and  the  stones  are 
crushed  and  10  per  cent,  of  honey  added,  and  the  whole  fermented. 
The  spirit  is  diluted,  and  kept  for  some  months  to  mature. 

Kuntmel. — Consists  of  brandy  flavoured  with  cumin  and  coriander. 
Vermouth. — Chiefly  made  in  Turin  from  white  wine  flavoured  and 
rendered  bitter  with  Pontic  wormwood  and  orange  wine,  and 
sweetened  by  the  addition  of  20  per  cent,  of  sugar. 

Chartreuse. — Originally  made  at  the  chief  Carthusian  monastery, 
near  Grenoble,  in  France,  and  also  at  Florence.  It  contains  a  large 
proportion  of  sugar,  the  flavour  being  derived  from  various  oils  con- 
tained in  angelica,  hyssop,  nutmeg,  peppermint,  and  other  herbs. 

Benedictine  is  a  very  similar  product,  made  at  the  Abbey  of 
Fecamp. 

Angostura  is  now  chiefly  made  at  Trinidad,  but  formerly  at  Angos- 
tura, the  chief  flavouring  ingredient  being  the  bark  of  that  name, 
though  other  species  are  also  added. 

Ratafia  is  a  name  now  applied  in  France  to  various  liqueurs  made 
from  spirit,  sugar,  and  aromatic  herbs.  It  derived  its  name  from 
the  fact  that  it  used  to  be  drunk  at  the  ratification  of  compacts  and 
bargains. 

The  action  of  spirits  on  digestion  is  practically  identical  with  that 
of  pure  alcohol.  They  can  only  delay  digestion  in  virtue  of  the 
alcohol  which  they  contain,  and  then  only  in  intoxicating  doses.  In 
moderate  quantity  their  influence  is  probably  favourable  rather  than 
otherwise,  just  as  is  that  of  alcohol  itself.  Their  acidity  is  so  slight 
that  they  have  but  a  small  effect  on  salivary  digestion. 

Liqueurs  taken  at  the  end  of  a  heavy  meal  may  perhaps  give  a 
fillip  to  digestion,  and  counteract  to  some  extent  any  retarding  in- 
fluence of  coffee  taken  at  the  same  time,  but  the  large  quantity  of 
sugar  which  they  contain  makes  them  irritating  to  an  empty  stomach 
and  possible  causes  of  acidity. 

In  studying  the  general  action  of  spirits  on  the  body,  one  must 


362  FOOD  AND  DIETETICS 

distinguish  carefully  between  the  action  of  the  alcohol  itself  and  that 
of  the  bye-products  of  fermentation  which  occur  along  with  it.  It 
would  be  a  great  mistake  to  regard  spirits  as  simply  mixtures  of 
alcohol  and  water  in  nearly  equal  proportion,^ 

Their  high  alcoholic  strength  renders  all  forms  of  spirits  valuable 
stimulants  where  the  action  of  alcohol  pure  and  simple  is  desired. 
For  such  a  purpose  whisky  is  as  good  as  any  other,  and  pot-still  or 
malt  whisky  possesses  no  real  advantages  other  than  flavour  over 
the  patent-still  or  grain  spirit. 

In  cases  of  profound  nervous  and  cardiac  exhaustion,  on  the  other 
hand,  especially  if  delirium  be  present,  one  does  not  want  merely  an 
action  upon  the  heart,  but  that  stimulating  influence  upon  the  brain 
and  vital  centres  which  the  volatile  bye-products  seem  to  be  alone 
capable  of  exerting.  Pot-still  whisky,  rum,  and  genuine  brandy 
possess  these  bye-products,  and  especially  those  of  an  ethereal  nature, 
in  largest  proportion,  and  therefore  are  much  to  be  preferred  in  such 
a  case.  It  is  important,  however,  that  these  spirits  should  be  old 
and  well  matured,  for  it  is  only  then  that  they  become  really  rich  in 
ethereal  bodies,  and,  of  the  three,  genuine  liqueur  brandy  is  far  the 
best.^  In  a  case  presenting  signs  of  profound  nervous  and  cardiac 
prostration  the  best  liqueur  brandy  should  alone  be  employed,  no 
matter  how  much  one  has  to  pay  for  it.  There  can  be  no  doubt 
that  its  free  and  timely  administration  has  saved  many  lives. 

'  It  is  when  our  patient  is  far  beyond  the  region  of  controversy, 
and  life  itself  is  "in  the  balance,"  that  I  find  a  sphere  of  marvellous 
usefulness  for  the  best  liqueur  brandy,  or,  in  lieu  of  it,  very  old 
cognac.  Brandy,  or  even  whisky,  where  the  alcohol  has  been 
changed  by  age  and  original  quality  into  vinous  and  ethereal  spirit, 
is  almost  a  pure  stimulant,  and  hardly  an  intoxicant  or  narcotic  at 
all.  .  .  .  Low  forms  of  bronchitis  and  congestion  of  the  lungs,  the 
extreme  exhaustion  of  some  forms  of  influenza,  the  later  stages  of 
typhoid,  cases  of  worn-out  stomach  from  gastric  catarrh,  cases  of 
breakdown  from  overwork,  etc.,  all  of  them  characterized  by  weak- 
ness of  heart,  failing  circulation,  inability  to  take  food,  loss  of  the 
power  to  sleep,  and  exhaustion,  come  into  the  category  of  suitable 
cases '  (Murray). 

*  It  is  only  right  to  mention  that  the  bulk  of  the  medical  evidence  given  before 
the  Royal  Commission  on  Whisky  was  in  favour  of  the  view  that  the  results 
obtained  from  whisky  in  the  treatment  of  disease  are  due  essentially  to  the  ethylic 
alcohol  which  it  contains.  See  also  Charteris  and  Cathcart  ('The  Physiological 
Action  of  Whisky  on  the  Circulation  '),  Brit.  Med.  Journ.,  1907,  i.  1174. 

"  See  Anstie,  '  On  the  Uses  of  Wines  in  Health  and  Disease,'  p.  44,  and 
Murray,  '  Liqueur  Brandy  '  ('  Rough  Notes  on  Remedies'),  third  edition,  p.  135. 


USES  OF  SPIRITS  363 

Spirituous  liquors  are  too  highly  alcoholic  for  ordinary  dietetic 
use  unless  taken  in  great  moderation  and  freely  diluted.  Two  or 
three  glasses  of  whisky  or  brandy  contain  as  much  alcohol  as  most 
people  can  safely  consume  in  one  day.  If  this  limit  be  observed, 
however,  and  the  spirit  freely  diluted,  they  may  agree  well,  owing  to 
their  almost  complete  freedom  from  sugar  or  acids. 

It  is  of  interest  to  inquire  at  this  point  what  constitutes  the  differ- 
ence between  a  good  and  a  bad  spirit.  Why,  for  instance,  does  a 
crude  whisky  produce  headache,  furred  tongue,  and  derangement  of 
digestion,  while  a  well-matured  spirit  has  no  such  eflFects  ?  and  why 
does  one  produce  sudden  and  almost  maniacal  intoxication  while 
another  does  not  ?  Much  as  this  question  has  been  discussed,  it 
must  be  confessed  that  no  satisfactory  reply  to  it  is  yet  forthcoming. 
One  may  wade  through  the  evidence  given  by  experts  before  the 
Commission  on  British  and  Foreign  Spirits,  or  that  on  Whisky,  and 
find  nothing  but  confusion  and  contradictory  statements. 

The  public  have  a  general  notion  that  the  bad  effects  of  immature 
spirits  are  due  to  the  presence  of  fusei-oil.  Let  us  inquire  into  this 
for  a  moment.  We  have  seen  that  '  fusel-oil '  is  really  a  mixture  of 
alcohols  of  higher  boiling-point  than  ethyl  alcohol.  The  exact  nature 
of  these  alcohols  varies  with  the  source  of  the  distillate.  In  brandy 
and  patent-still  whisky  propylic  alcohol  is  the  chief  one  present ; 
the  fusel-oil  of  malt  whisky  and  rum  consists  mostly  of  butylic  and 
amylic  alcohol.  Now,  experiments  have  certainly  shown^  that  these 
higher  alcohols  have  a  much  greater  toxic  action  than  ordinary  ethyl 
alcohol.  But  even  in  a  bad  whisky  there  is  not  more  than  ^  per 
cent,  of  fusel-oil  present  (about  a  grain  to  the  glassful),  and  by 
experiment  it  is  known  that  at  least  i  per  cent,  is  required  to  pro- 
duce any  marked  effects.  Further,  the  effects  of  fusel-oil  have  been 
put  to  direct  tests  in  the  human  subject.  King  Chambers  2  says 
that  he  gave  fusel-oil  to  various  people  in  doses  of  from  i  to  10  drops, 
with  the  result  of  producing  feverishness,  furred  tongue,  throbbing 
of  the  temples,  and  headache  ;  but  other  observers  failed  to  get 
these  results.  Allen,'  for  instance,  swallowed  for  a  month  con- 
siderable quantities  of  whisky  to  which  he  had  added  as  much  as 
2  per  cent,  of  fusel  -  oil  without  experiencing  any  bad  results. 
Mr.  Samuel,  F.C.S.,  stated  before  the  Commission  on  Spirits  that 

^  See  Dujardin  Beaumetz, '  L'Hygiene  Alimentaire ' ;  Richet's  '  Dictionary  ol 
Physiology,'  article  '  Aicohor  ;  and  Binz's  'Lectures  on  Pharmacology,'  N.S., 
'895,  i.  347  ;  also  Baer,  Archiv.  f.  Anat.  und  Physiol ,  1898  (Phys.  Abth.),  283,  and 
Jeffrey  and  Serveau,  Archives  de  Med.  Exper.,  i8gj,  ir.  681. 

*  '  Manual  of  Diet  in  Health  and  Disease,'  p.  78. 

»  Journai  of  thi  Socitty  «/Cktmical  Industry,  April  30,  1891, 


364  FOOD  AND  DIETETICS 

he  had  consumed  4  ounces  of  brandy  a  day  for  four  days  containin(» 
^  per  cent,  of  fusel-oil,  and  found  no  bad  effects  from  it.  This 
quantity  was  equivalent  to  24  ounces  of  ordinary  brandy  with  -^  per 
cent,  of  fusel-oil.  Finally,  Zuntz^  has  stated  that  when  a  controversy 
about  fusel-oil  was  raging  some  years  ago  he  gave  patients  consider- 
able doses  of  it  in  capsule,  and  never  observed  any  bad  symptoms 
in  the  form  of  indigestion,  headache,  etc. 

When  we  add  to  these  results  the  fact  that  it  is  by  no  means 
clearly  proved  that  old  whisky  is  poorer  in  fusel-oil  than  young,  it 
must  be  admitted  that  one  can  no  longer  regard  the  traces  of  higher 
alcohols  in  spirits  as  being  responsible  for  the  bad  effects  which 
these  liquors  sometimes  produce.  One  is  consequently  confined  to 
the  supposition  that  the  offending  material  is  to  be  found  amongst 
the  other  bye-products  of  fermentation,  probably  aldehydes  such  as 
Furfurol,  while  the  local  irritating  effects  of  immature  spirits  on 
the  stomach  may  be  due  to  some  empyreumatic  body,  e.g.,  pyridine.' 

As  regards  the  greater  intoxicating  effect  of  crude  spirits,  it  must 
be  pointed  out  that  these  may  be  due  to  the  quantity  and  not  to 
the  quality  of  the  liquor  consumed,  for  spirits  lose  a  considerable 
proportion  of  alcohol  when  stored  in  wood.  Binz  has  made  the 
ingenious  suggestion  that  some  of  the  volatile  ethers,  produced  in  old 
spirits  by  oxidation,  act  as  correctives  to  the  action  of  alcohol,  much 
as  atrophine  does  to  morphia,  but  of  this  there  is  as  yet  no  experi- 
mental proof. 

Malt  Liquors. 

This  group  includes  beer  or  ale,  and  porter  or  stout.  There  is 
some  confusion  in  the  use  of  these  names,  and  they  have  not  quite 
the  same  meaning  in  all  parts  of  the  country.  In  some  places  the 
term  '  ale '  is  appHed  to  the  brown  beverages,  while  the  black  drinks 
are  spoken  of  as  '  beers.'  It  is  better  to  regard  the  terms  '  ale  *  and 
*  beer '  as  synonymous,  and  to  apply  them  to  the  paler  liquors,  and 
to  speak  of  the  blacker  drinks  as  stouts  or  porters.  There  is  some 
reason,  however,  to  believe  that  ale  and  beer  were  not  originally 
identical,  but  that  the  former  term  was  the  earlier,  '  beer '  being  only 
employed  subsequent  to  the  introduction  of  hops. 

Beer  may  be  defined  as  the  product  of  the  fermentation  of  malt 
and  hops.  We  shall  see  later  that  much  of  the  '  beer '  in  common 
use  has  not,  strictly  speaking,  quite  this  origin. 

»  Deut.  Med,  Wochensch.,  1893,  xix.  466.  _       t   •     • 

»  For  a  full  discussion  of  this  subject  see  a  paper  (' Concerning  Tniurious 

Constituents  in  Whisky,  and  their  Relation  to  Flavour'),  by  Lauder  Brunton 

and  Tunnicliffe.  Lancet,  1902.  i.  1591. 


MALT  LIQUORS  365 

Malt  is  obtained  by  moistening  barley  and  allowing  it  to 
germinate  in  heaps  at  a  moderate  and  regular  temperature.  During 
germination  important  changes  take  place  :  the  ferment  diastase 
appears  in  the  grain  and  acts  upon  some  of  the  starch,  converting  it 
into  dextrin  and  malt-sugar,  while  part  of  the  proteins,  by  the  action 
of  another  ferment,  is  also  converted  into  soluble  forms.  The 
*  green  malt '  so  produced  is  next  dried,  and  upon  the  exact 
temperature  at  which  this  is  carried  out  the  character  of  the  beer 
largely  depends,  for  the  lower  (within  limits)  the  temperature 
employed,  the  more  powerful  is  the  action  of  the  ferments  contained 
in  the  grain,  and  the  larger  the  amount  of  soluble  substances 
produced.  Low-dried  malts  produce  pale  beer;  those  dried  at  a 
highe    temperature  yield  a  darker  product. 

When  drying  is  complete,  the  malt  is  ground  and  made  into  a 
mash  with  w^ater.  Rather  hard  waters  yield,  for  some  reason,  the 
best  beer,  the  water  of  Burton-on-Trent  being  apparently  specially 
well  suited  for  the  purpose,  and,  indeed,  in  most  breweries  the  water 
is  artificially  made  up  to  the  standard  of  that  locality. 

After  mashing,  the  wort  is  strained  off  from  the  malt  and  boiled 
for  an  hour  or  two  with  hops.  Boiling  stops  any  further  action  of  the 
diastase,  and  extracts  from  the  hops  their  soluble  ingredients.  Chief 
amongst  these  are  tannic  acid  and  certain  resinous  bodies  of  bitter 
taste.  A  substance  called  'hopein,'  the  nature  of  which  has  not 
been  fully  investigated,  but  which  seems  to  have  properties  re- 
sembling those  of  morphia,  is  also  extracted.  '  Lupulin,"  which  is 
the  secretion  of  the  glands  of  the  hop,  does  not  seem  to  be  present 
in  the  finest  varieties.  The  boiled  wort  is  next  pumped  out  and 
rapidly  passed  over  coolers,  and  is  then  ready  for  the  addition  of  the 
yeast.  Great  care  is  now  taken  to  employ  pure  yeast,  for  many  of 
the  diseases  of  beer,  such  as  the  development  in  it  of  acetic  acid,  are 
due  to  contamination  with  *  wild '  yeasts.  Scientific  brewing  has 
made  great  progress  in  this  direction  in  recent  years.  The  yeast 
is  added  to  the  wort  in  vats,  and  fermentation  is  then  allowed 
to  proceed.  Here,  again,  much  depends  upon  the  temperature 
employed.  In  this  country  fermentation  is  usually  conducted  at 
rather  high  temperatures,  with  the  result  that  most  of  the  sugar  is 
broken  up  and  the  resulting  beer  is  rich  in  alcohol.  In  Germany 
low  temperatures  are  employed,  and  more  sugar  and  dextrin  are 
left  in  the  beer,  but  less  alcohol  is  produced.  Low-fermentation 
beers  also  contain  more  carbonic  acid  than  most  English  beers,  and 
are  therefore  better  aerated.     It  is  thus  that  lager-beer  is  produced. 

When  fermentation  is  complete,  the  yeast,  which  has  been  carried 


366  FOOD  AND  DIETETICS 

to  the  surface,  is  skimmed  off,  and  the  beer  is  allowed  to  stand  in 
shallow  tanks  till  most  of  the  remaining  yeast  has  settled  to  the 
bottom.  It  is  then  run  off  into  casks.  Here  a  secondary  fermenta- 
tion occurs  under  the  action  of  the  small  quantity  of  yeast  still 
contained  in  the  beer,  but  it  is  restrained  to  some  extent  by  the 
addition  to  the  cask  of  an  extra  quantity  of  hops.  The  longer  this 
lasts,  the  greater  is  the  amount  of  alcohol  produced,  and  if  strong 
beer  is  desired  it  must  be  left  in  the  cask  for  some  months.  At  the 
same  time  some  volatile  bodies  seem  to  be  developed  which  impart 
to  such  beer  its  full  flavour,  while  the  production  of  more  carbonic 
acid  under  pressure  leads  to  partial  solution  of  that  gas,  and  gives 
to  the  liquor  a  pleasant  sharp  taste.  Just  before  bottling  a  solution 
of  isinglass  in  acetic  or  tartaric  acid  ('  finings ')  is  added  to  the  cask, 
which  soon  settles  down  in  the  form  of  a  precipitate,  carrying  with 
it  any  remaining  yeast  cells  and  other  impurities. 

After  bottling,  the  beer  becomes  brisker  than  it  was  in  the  cask, 
probably  because  no  gas  can  now  escape  from  it.  Strong  beer  will 
keep  well  in  bottle  for  eighteen  months. 

The  taste  for  strong,  full-flavoured  ales  seems  now  to  be  passing 
away,  and  a  weaker  and  milder  beverage  is  more  largely  produced, 
which,  from  the  rapidity  with  which  it  goes  into  consumption,  is 
termed  *  running  ale  ';  carbonic  acid  is  often  added  to  it  by  artificial 
aeration,  and  in  order  to  insure  its  keeping  an  antiseptic  is  frequently 
added,  especially  in  hot  weather.  Sulphite  of  calcium  is  largely 
employed  for  the  purpose.  It  falls  down  quickly  in  the  form  of 
sulphate  and  does  no  harm.  Salicylic  acid  is  also  used,  but  as  not 
more  than  |  ounce  is  usually  added  to  a  36-galIon  cask,  it  may  be 
regarded  as  quite  innocuous.  It  is  apt,  however,  to  affect  the  flavour 
of  the  beer  to  some  extent. 

The  names  applied  to  different  beers  vary  in  different  breweries, 
and  many  of  the  commercial  brands  are  made  by  the  judicious 
blending  of  beers  produced  in  different  ways.  One  can  distinguish 
broadly  between  mild  and  bitter  ales,  the  former  containing  relatively 
more  malt  and  less  hops  than  the  latter,  while  in  mild  the  malt  is 
also  dried  at  a  higher  temperature. 

Indian  Pale  Ale  is  so  called  because  it  was  first  produced  for  the 
Indian  market.  It  is  very  thoroughly  fermented,  and  contains,  there- 
fore, but  little  sugar,  and  being  highly  hopped  it  has  good  keeping 
properties,  for  the  hops  act  as  an  antiseptic. 

In  an  ordinary  public-house  the  varieties  usually  distinguished 
are  'four-ale'  [i.e.,  4d.  per  quart),  which  is  the  poorest;  *  six-ale' 


VARIETIES  OF  ALE  367 

(6d.  per  quart),  which  is  a  mixture  of  mild  and  bitter  and  comes 
next ;  and  after  that  '  bitter '  and  '  Burton/  the  last  being  the 
strongest  of  all. 

The  description  of  brewing  given  above  applies  only  to  *  pure  * 
beers — that  is  to  say,  to  beverages  brewed  only  from  malt  and  hops. 
A  very  large  proportion,  however,  of  the  beer  in  ordinary  consump- 
tion has  not  this  origin,  some  cheaper  source  of  sugar  than  malt 
being  employed.  Amongst  the  substitutes  so  used  are  invert  sugar, 
potato  glucose,  flaked  maize  and  rice ;  and  the  liquor  produced  from 
them  is  sometimes  termed  substitute  beer. 

A  large  amount  of  evidence  concerning  the  production  of  these 
beers  and  their  effects  upon  health  was  given  before  a  Parlia- 
mentary Commission  a  few  years  ago,  but  it  must  be  admitted 
that  the  results  were  not  very  definite  or  satisfactory.  It  would 
appear  that  it  takes  an  expert  to  tell  the  origin  of  a  beer  from 
its  flavour,  and  it  was  certainly  not  clearly  shown  that  the 
'  substitute '  beers  are  really  injurious  to  health,  while  they 
can  undoubtedly  be  produced  more  cheaply  than  the  genuine 
article.^ 

Porter  or  stout  is  made  in  the  same  way  as  beer,  but  the  malt  is 
first  roasted  in  cylinders,  much  as  coffee  is.  This  has  the  effect  of 
producing  some  caramel,  to  which  the  dark  colour  of  these  beverages 
is  mainly  due,  and  it  must  also,  by  killing  the  diastase,  prevent  the 
further  production  of  dextrin  and  sugar  in  mashing.  The  propor- 
tion of  solid  matter  in  the  liquor  is  often  enhanced  by  the  artificial 
addition  of  caramel  or  of  invert  sugar. 

German  beers,  as  has  been  mentioned,  are  fermented  at  a  lower 
temperature  than  those  of  this  country,  and  contain  more  dextrines 
Secondary  fermentation  takes  place  in  them  to  a  large  extent,  and 
produces  much  carbonic  acid  gas.  They  are  decidedly  less 
alcoholic,  and  more  nourishing  than  English  beers. 

1  Since  the  above  was  written  an  epidemic  of  arsenical  poisoning  has  occurred 
from  the  consumption  of  '  substitute  '  beer  prepared  from  impure  glucose.  Too 
much  importance,  however,  must  not  be  attached  to  such  an  accidental  occur- 
rence in  deciding  the  question  of  the  relative  wholesomeness  of  '  pure  '  and 
•  substitute  '  beers.  The  statement  still  holds  good  that  provided  the  materials 
used  in  its  manufacture  are  free  from  impurity  '  substitute  '  beer  has  not  beea 
■howa  to  be  injurious  to  health. 


368  FOOD  AND  DIETETICS 


Composition  of  Malt  Liquors. 

The  most  important  constituents  of  these  beverages  are 
alcohol,  dextrins,  sugar,  and  a  small  amount  of  soluble  nitrog- 
enous matter  (together  these  make  up  the  *  extract '),  and  vege- 
table acids. 

The  following  table^  gives  the  approximate  composition  of  some 

of  these  beverages : 

Alcohol.  J,  .  ,                                                     Acidity 

Wafer.   Percent.  J  !    ,    Protein.  Suirar.    Dextnns.  as  Lactic  Ash. 

by  vol.  ^^'''''''-                                                    Acid. 
Bavarian  winter 

beer  ..  ..  giSi  3-21  499  oSi  044  292  o-ii6  020 
Bavarian  summer 

beer    ..         ..  9071      368  561        049        087         439         0128     022 

Munich  Hofbrau     —        370  587 

Spatenbrau       ..     —         3'23  661 

Pilsener..          ..  9115      346  497        o'37          —            —              O'^^     °'20 

Munich  Bockbier  8872      407  723        071         090          —             017      027 
En°;lish  ale  and 

porter..         ..  Sg-i        489  603        053        084          —             031      031 

Berlin  white  beer     —         3'9i         4'83  —  —  —  —         — 

AUsopp's  Lager     89-49     5-40  —  040        204         3-34  0-12      0-27 

The  following  is  an  analysis  of  Burton  pale  ale  by  Chittenden  and 
MendeP : 

Alcohol       ..         ..     4  to  525  per  cent,  by  vol. 
Extract       ..         ••     4"4  1.  „ 

Ash 035 

The  composition  of  two  good  specimens  of  stout  is  thus  given  by 

the  Lancet^ : 

'Oat  Stout.'  '  Nourishing  Stout.' 

Extract 63  per  cent.  80  per  cent. 

624      ..  655      „ 

50  ..  5-25  M 

090      ,, 

045      ..  o"33      ,. 


Alcohol  by  vol. 

,,        by  weight 
Acidity    . . 
Ash 


Chittenden  and  Mendel 
as  follows : 


s  analysis  of  Guinness's  Dublin  Stout  is 


Alcohol  (by  vol.)  ..         ..     5-5  per  cent. 

Extract 5'42 

Ash  036      ., 


1  From  Leyden's  '  Handbuch  der  Ernahrungs  Therapie,'  i.  103. 

*  American  Journal  of  the  Medical  Sctencei,  1896,  cxi.  177. 

•  1897,  ii.  314;  ibid.,  1898,  i.  1408. 


ACTION  AND  USES  OF  MALT  LIQUORS         369 

It  has  been  calculated  that  the  chief  ingredients  of  a  pint  (20  ounces) 
of  good  average  bottled  beer  are  these : 

Alcohol       . .         . ,         . .  I  fluid  ounce. 

Extract i  to  2  ounces. 

Free  acids 25  grains. 

Salts  13      .. 

Action  and  Uses  of  Malt  Liquors. 

I.  Action  on  Digestion. — Malt  liquors  have  but  little  retarding  in- 
fluence on  salivary  digestion,  and  what  action  they  do  possess  is 
entirely  due  to  their  acidity.  Stout  is  twice  as  acid  as  beer,  and 
hence  has  a  greater  retarding  action  on  the  digestion  of  starch  by  the 
saliva. 1  Sound  beer,  indeed,  in  some  experiments,^  seemed  actually 
to  increase  rather  than  restrain  the  action  of  ptyalin,  but  sour  beer  has 
a  decidedly  retarding  effect.^  On  the  other  hand,  in  the  living  body 
the  bitterness  of  beer  may  bring  about  a  more  profuse  flow  of  saliva, 
and  so  end  by  improving  rather  than  impairing  salivary  digestion. 

In  the  stomach  beer  does  not  remain,  if  taken  alone,  any  longer 
than  water,  for  200  c.c.  are  found  to  have  completely  left  it  in  about 
one  and  a  half  hours.  If  taken  with  other  food,  it  delays  the  chemical 
processes  of  digestion  more  than  the  mere  amount  of  alcohol  which 
it  contains  will  explain.  Some*  have  blamed  the  '  extract '  for  this, 
others  the  salts  ;5  but  the  action  is,  in  any  case,  not  an  important 
one,  for  even  half  a  litre  of  beer  (about  a  pint),  when  taken  with  a 
mixed  meal,  was  found  to  produce  but  very  little  delay  in  the 
stomach.«  It  is  probable,  indeed,  that  a  tumblerful  of  good,  brisk 
beer  may  actually  aid  digestion  by  increasing  appetite  and  calling 
out  a  more  abundant  secretion  of  gastric  juice  and  more  active 
movements  of  the  stomach. 

Malt  liquors  seem  sometimes  to  give  rise  to  '  acidity  '  in  the 
stomach.  This  may,  perhaps,  be  the  result  of  acid  fermentation  of 
the  liquor,  especially  if  it  has  not  been  kept  very  long  in  the  cask. 

Beer  is  found  by  some  persons  to  have  an  unfavourable  influence 
on  the  liver,  producing  a  sort  of  dyspeptic  sluggishness.  The  way 
in  which  it  does  this  is  not  fully  understood,  nor  whether  it  is  to  be 
attributed  to  the  malt  or  some  ingredient  of  the  hops.  It  is  for  this 
reason,  amongst  others,  that  beer  is  not  a  good  beverage  for  the 

*  Chittenden  and  Mendel,  op.  cit. 

*  Aitchison  Robertson,  Journal  of  Anatomy  and  Physiology,  1898,  xxiii.  615. 

*  Roberts,  'Digestion  and  Diet,'  p.  119. 

*  Simanowsky,  Arch.  f.  Hygient,  1886,  iv.  i. 

*  Buchner,  Deut.  Archiv.  f.  Klin.  Med.,  1S81,  xxix.  537, 
«■  Buchner,  op.  cit^ 

H        ■ 


370  FOOD  AND  DIETETICS 

sedentary  unless  in  very  moderate  amount.  Stout  is  popularly 
believed  to  be  more  '  digestible,'  and  perhaps  rightly,  but  bottled 
stout  is  an  admirable  soporific.  *  If  it  be  desired  to  avoid  nervous- 
ness,' says  Hutchinson,  '  and  to  get  rid  of  insomnia,  shun  tea  and 
coffee,  and  drink  Guinness's  stout.  ...  I  scarcely  ever  met  with  a 
man  who  could  withstand  the  soporific  effects  of  bottled  stout.  It 
is  far  better  than  opium,  and  induces  a  more  nearly  natural  sleep.' 
It  is  interesting  in  this  connection  to  note  that  the  residue  of  dried 
beer  is  found  to  have  a  sedative  influence  very  much  like  that  of 
morphia ;  this  has  been  ascribed  to  '  hopein,'  one  of  the  soluble 
constituents  of  hops. 

2.  Influence  as  Foods. — The  large  quantity  of  carbohydrate  matter 
in  malt  liquors  renders  them  the  most  truly  nourishing  of  alcoholic 
drinks.  A  pint  of  good  ale  contains  as  much  carbohydrate  as 
i\  ounces  of  bread. 

I  found  the  following  amount  of  solids  in  some  common  varieties : 

Grammes  in  loo  C.e. 

Pilsener  Lager  (Bremen)       ..         .,         ,.  27 

Amsterdam  Pilsener   ..         ..         ..         ..  41 

Allsopp's  Light  Dinner  Ale 52 

Bulldog  Stout 6-6 

Bottled  Lager  (Biirgerbrau) 68 

Nourishing  Stout  (Mountjoy  Brewery)      ..  92 

According  to  these  figures,  an  imperial  pint  of  Allsopp  contains 
30  grammes  of  solid  matter,  and  has  in  addition  about  36  c.c.  of 
alcohol.  Together  these  will  yield  about  337  Calories  of  energy,  and 
2  pints  will  contain  one-fifth  of  the  total  energy  required  daily.  A 
glass  of  milk  yields  about  184  Calories,  a  similar  glass  of  good 
bottled  beer  about  168.  It  does  not  follow  from  this,  however,  that 
beer  is  almost  as  good  a  source  of  energy  as  milk,  for,  as  we  have 
seen,  alcohol  is  to  be  regarded  as  a  food  of  only  limited  value.  Five 
litres  of  good  German  beer  vnth.  5  per  cent,  of  '  extract '  should  yield 
250  grammes  of  carbohydrate  (1,025  Calories),  which  is  half  the 
total  required  daily,  and  in  addition  100  to  150  grammes  of  alcohol, 
with  a  fuel  value  of  700  to  i  ,050  Calories. 

Malt  liquors  must  be  strictly  forbidden  in  many  forms  of  disease. 
The  combined  effects  of  their  alcohol  and  carbohydrates  render  them 
specially  prone  to  produce  obesity,  and  they  are  also  to  be  regarded 
as  frequent  predisposers  to  gout.  In  all  cases  of  inflammation  of 
the  mucous  membrane  of  the  genito-urinary  tract,  also,  they  seem, 
for  some  reason,  to  have  a  peculiarly  bad  effect,  and  the  recurrence  of 
a  gleet,  for  instance,  can  often  be  traced  to  their  use.  They  are  too 
rich  in  carbohydrates  to  be  suitable  for  any  but  the  mildest  cases  of 


MALT  LIQUORS  AND  DIGESTION  371 

diabetes.  Special  beers  are  prepared,  however,  which  contain  very 
little  extract  and  no  sugar,  and  these  can  be  safely  recommended  in 
cases  of  obesity  or  diabetes. 

It  must  be  remembered  also  that  malt  liquors  are  bulky  drinks,  and 
indulgence  in  them  introduces  a  large  amount  of  fluid  into  the 
circulation.  The  effort  to  expel  this  surplus  fluid  throws  an  extra 
strain  on  the  heart,  which  may  be  very  injurious  if  that  organ  is 
already  damaged.  In  Bavaria  a  special  form  of  hypertrophy  of  the 
heart  ('  beer-heart ')  is  not  uncommonly  produced  in  this  way,  even 
in  otherwise  healthy  persons.^ 

Some  very  good  non-alcoholic  beers  are  now  manufactured,  and 
may  be  conveniently  mentioned  here.  Best  known  of  these  is 
Kops  Ale,  which  contains  about  07  per  cent,  of  solids  and  less 
than  J  per  cent,  of  alcohol.  Other  excellent  preparations  of  the  same 
class  are  Barrie's  Bitter  Beer,  the  Banks  Company's  Ales,  and  the 
products  of  the  Nonal  Company.  These  possess  the  tonic  and 
digestive  actions  of  beer  without  its  stimulating  effects,  and  are  a 
decided  advance  upon  most  *  temperance '  beverages. 

^  See  Von  Striimpell,  6jten  Versamml.  deat.  Naturforscher  uad  Arzte  zu 
Nurnberg,  p.  97,  1893. 


I  372  J 


CHAPTER  XXI 
ALCOHOLIC  BEVERAGES  (continued)  :  WINESi 

Wine  may  be  defined  as  a  beverage  produced  from  the  pure  juice  of  the 
grape  by  fermentation.  Some  add  to  this  definition  the  saving  clause, 
'or  with  such  additions  only  as  are  believed  to  improve  its 
durability.*  The  quality  of  the  wine  depends  very  much  upon  the 
variety  of  the  grape,  the  soil  upon  which  it  is  grown,  the  mode  in 
which  it  is  cultivated,  and  the  climatic  conditions  of  particular  years. 
The  juice  is  obtained  by  crushing  the  grapes,  treading  being  the 
method  usually  employed  in  order  to  avoid  squeezing  the  stalks  and 
stones  too  much,  and  so  extracting  undesirable  ingredients. 

The  chief  chemical  constituents  of  the  juice  are  sugar,  albuminous 
matters  and  certain  acids,  of  which  the  most  abundant  are  tartaric 
and  tannic  acids.  The  sugar  is  a  mixture  of  grape-sugar,  or  dextrose, 
and  fruit-sugar,  or  laevulose,  in  the  proportion  of  about  three  parts  of 
the  former  to  one  of  the  latter. 

The  relative  amount  of  albuminous  matter  and  sugar  in  the  juice 
has  much  influence  on  the  character  of  the  wine  produced.  The 
yeast  lives  upon  the  albuminous  matter,  and  splits  up  the  sugar,  with 
the  formation  of  alcohol  and  other  products.  If  there  be  but  little 
sugar  and  much  albuminous  matter  present,  the  yeast  can  go  on 
growing  until  all  the  sugar  is  split  up.  The  wine  will  then  be  '  dry  ' 
and  of  an  acid  taste.  Such  a  wine  is  hock.  If,  on  the  other  hand, 
the  sugar  is  out  of  all  proportion  to  the  albuminous  substances  in 

1  In  obtaining  material  for  this  chapter,  the  author  has  been  much  indebted  to 
the  following,  among  other,  publications :  Thudichum  and  Dupre,  '  A  Treatise 
on  the  Origin,  Nature  and  Varieties  of  Wine,'  London,  1872;  Thudichum,  'A 
Treatise  on  Wines,'  Bohn's  Scientific  Library,  1896 :  in  the  preface  references  will 
be  found  to  most  other  modern  works  on  the  subject ;  Gautier,  '  La  Sophistication 
des  Vins,'  1884  ;  Mulder,  '  On  the  Composition  of  Wines  '  (edited  by  Bence  Jones), 
1857  ;  Dupre,  '  What  is  Wine  ?'  [Popular  Science  Review,  1868,  vii.  354) ;  Windisch, 
*  Die  Chemische  Untersuchung  und  Beurtheilung  des  Weines,'  Berlin.  1896 ; 
Anstie,  '  On  the  Uses  of  Wines  in  Health  and  Disease,"  Macmillan  and  Co., 
London,  1S77  ;  'In  Vino  Veritas'  (edited  by  Andre  L.  Simon),  Grant  Richards, 
Ltd.,  London,  1913.     References  to  other  papers  will  be  found  in  the  text.. 


FERMENTATION  OF  WINE  373 

the  juice,  a  limit  is  set  to  the  growth  of  the  yeast,  and  some  sugar 
will  be  left  in  the  wine,  and  it  will  then  taste  sweet.  Should,  how- 
ever, the  sugar  and  albuminous  matter  be  present  in  more  equal 
amount,  the  wine  will  retain  some  of  both,  and,  though  not  sweet, 
will  not  have  a  distinctly  acid  flavour  either,  and  will  be  of  full 

*  body.'  Such  a  wine  is  burgundy.  It  must  be  remembered,  more- 
over, that  no  matter  how  much  albuminous  substance  and  sugar  the 
juice  may  contain,  the  production  of  alcohol  cannot  go  on  in- 
definitely, for  the  accumulated  alcohol  ultimately  ends  by  paralyzing 
the  yeast.  This  takes  place  when  the  proportion  of  alcohol  in  the 
fermenting  liquid  has  reached  about  16  per  cent,  by  volume. 
Hence  it  is  that  a  '  natural '  wine  can  never  contain  more  alcohol 
than  this ;  indeed,  there  is  rarely  so  much  sugar  present  in  the  juice 
as  to  allow  of  its  containing  so  much.^  If  a  wine  contains  more 
than  16  per  cent,  of  alcohol  by  volume,  one  may  be  quite  sure  that 
spirit  has  been  added  to  it  artificially ;  that  is  to  say,  it  has  been 
'  fortified.'      Sherry  and  port  as  sold   in    this  country  are  always 

*  fortified '  wines ;  claret  and  hock,  on  the  other  hand,  are  *  natural ' 
wines. 

The  colour  of  red  wines  is  due  to  a  pigment  contained  in  the  skins 
of  the  grapes,  which  is  turned  red  by  the  acids  of  the  juice.  As  the 
skins  are  left  in  the  vat  in  making  such  wines,  the  alcohol  which  is 
produced  gradually  dissolves  out  this  pigment,  and  so  the  wine 
acquires  its  red  or  purple  tint.  The  colour  of  the  white  or  brown 
wines  is  mainly  due  to  the  oxidation  of  tannic  acid  in  the  cask. 

The  yeast  which  adheres  to  the  skin  of  the  grape,  and  which  is 
responsible  for  the  fermentation  of  wine,  is  different  from  the  yeast 
which  produces  the  fermentation  of  malt  liquors  or  spirits.  Further, 
we  now  know  that  the  characteristic  qualities  of  different  wines  are 
due,  in  some  measure  at  least,  to  the  fact  that  they  are  produced  by 
different  species  of  yeasts.  Thus,  the  yeast  concerned  in  producing 
hock  is  different  from  that  which  produces  claret,  and  by  growing  a 
hock  yeast  on  a  claret  '  must '  one  gets  a  wine  which  is,  as  it  were, 
a  cross  between  claret  and  hock,  and  has  some  of  the  distinctive 
characters  of  both.  Bacteriology  has  in  recent  years  come  to  the 
aid  of  the  wine-producer,  and  by  producing  pure  cultures  of  the 
different  yeasts  will  shortly,  no  doubt,  make  wine  production  a 
much  more  scientific  and  certain  process  than  it  has  hitherto  been, 
and  we  may  perhaps  look  forward  in  the  future  to  tasting  varieties 

'  In  order  to  produce  16  per  cent,  of  alcohol  in  the  wine,  there  must  be  34  per 
cent,  of  sugar  in  the  juice,  while  the  usual  proportion  of  sugar  in  the  juice  of  most 
grapes  is  only  from  13  to  30  per  cent.  Since  the  above  was  written,  however, 
some  natural  Australian  wines  have  been  found  to  contain  as  much  as  19  per 
cent,  of  alcohol  by  volume  (see  Lancet,  1901,  i.  802). 


374  FOOD  AND  DIETETICS 

of  wine  hitherto  quite  unknown.  I  have  already  pointed  out  that 
the  bacteriologist,  by  working  on  similar  lines,  has. already  done  this 
for  cheese. 

The  exact  details  of  the  process  of  fermenting  grape-juice  in  order 
to  produce  wine  from  it  vary  considerably  in  different  countries  and 
localities,  and  little  would  be  gained  by  attempting  to  describe  them 
in  detail.  As  a  rule,  the  first  fermentation  lasts  for  from  two  to  six 
weeks,  depending  largely  upon  temperature,  and  the  wine  is  left 
upon  the  lees  till  the  spring,  when  it  is  siphoned  off  for  storage. 
Prior  to  being  placed  in  the  cask,  it  is  *  racked  '  by  the  addition  of 
isinglass  or  white  of  egg,  much  as  beer  is  by  '  finings,'  in  order  to 
remove  albuminous  matters  (which  prevent  the  wine  from  keeping) 
and  suspended  impurities.  When  clear,  it  is  again  '  racked '  oflF 
from  the  deposit,  and  stored  in  casks  in  the  cellar. 

In  the  cask  many  very  important  changes  take  place  to  the  occur- 
rence of  which  the  ultimate  character  of  the  wine  is  largely  due. 
For  one  thing,  the  alcoholic  strength  of  the  wine  rises.  This  is  due 
to  the  fact  that  the  water  of  the  wine  soaks  into  the  wood  more  than 
the  alcohol  does,  and  is  lost  by  evaporation,  so  that  the  wine  becomes 
more  concentrated.  As  the  water  so  lost  is  replaced  by  the  addition 
of  more  wine,  the  increase  in  the  proportion  of  alcohol  is  rendered  all 
the  greater.  In  the  cask,  too,  a  partial  oxidation  of  the  tannic  acid 
takes  place.  This  causes  the  white  wines  to  become  darker  in 
colour,  but  has  just  the  reverse  effect  upon  the  red  wines ;  for  the 
oxidized  tannic  acid  unites  with,  and  carries  down,  some  of  their 
pigment. 

The  small  quantity  of  yeast  which  always  finds  its  way  into  the 
cask  produces  a  slow  secondary  fermentation  of  the  wine,  which  often 
lasts  for  years.  As  a  result  of  this,  some  of  the  remaining  sugar  is 
converted  into  alcohol,  and  in  this  way  also  the  alcoholic  strength  of 
the  wine  is  increased.  As  the  proportion  of  alcohol  rises,  some  of 
the  ingredients  of  the  wine,  such  as  tannic  acid  and  bitartrate  of 
potash,  become  less  soluble,  and  fall  down  in  the  form  of  a  deposit. 
During  this  time  also  some  of  the  alcohol  is  oxidized  into  acetic  acid, 
and  the  formation  of  compound  ethers  takes  place.  The  maximum 
quantity  of  these,  however,  is  usually  reached  in  about  five  years, 
for  the  presence  of  water  prevents  the  formation  of  ethers  continuing 
till  all  available  acids  are  used  up. 

After  bottling,  the  formation  of  ethers  still  goes  on,  possibly  with 
the  aid  of  micro-organisms,  but  the  alcoholic  strength  of  the  wine 
does  not  increase.  It  is  quite  a  mistake  to  suppose  that  wine  which 
has  been  kept  long  in  bottle  is  necessarily  stronger  than  a  younger 


CONSTITUENTS  OF  WINE 


S7S 


wine.  The  reverse  is  the  truth  ;  for  the  alcohol  seems  actually  to 
diminish  after  the  wine  has  been  bottled  some  years.  It  is  also  an 
error  to  suppose  that  wine  goes  on  improving  indefinitely.  Like  all 
other  organic  things,  it  is  liable  to  decay  by  the  slow  processes  of 
oxidation,  and  few  wines  really  improve  after  thirty  years ;  many, 
indeed,  such  as  clarets,  are  at  their  best  long  before  this,  and  it  is 
only  a  few  of  the  stronger  wines,  such  as  sherry  and  madeira,  which 
will  stand  keeping  for  fifty,  or  possibly  even  a  hundred,  years. 


•  Must '  contains  : 

Water. 

FrX'T}"*°3oper.eat 

Malic  add. 
Tartaric  acid. 
Racemic  acid. 
Albuminous  substances. 
•  Vegetable  mucus.' 
Essential  oils. 
Extractives. 
Mineral  substances. 
Tannic  acid 
Colouring  matters 
Fatty  substances 


from  the  skins  and 
kernels. 


hO-3  to  0-8  per  cent. 


Constituents  of  Wine. 

The  following  is  a  list  of  the  principal  constituents  found  in  grape- 
jaice,  or  ♦  must,'  and  in  the  wine  produced  from  it  (Dupr6)  :^ 

Wine  contains  : 

Water. 

Grape-sugar  j^^^gp„^^„t 

Ethylic  alcohol,  5  to  22  per  cent. 
Propylic     ,, 
Butylic       ,, 
Amylic        ,, 
Other  higher  alcohols. 
Malic  acid 
Tartaric  acid  ] 
Racemic 
Succinic 
Acetic 
Formic 
Propionic , 
Butyric     ,. 

Ethers  of  foregoing  alcohols  and  acids 
Glycerine. 
Aldehyde. 

Carbonic  acid  and  ammonia. 
Trimethylamin. 
Oils  produced  by  fermentation. 
Albuminous  matter. 
'  Vegetable  mucus.' 
Colouring  matter. 
Tannic  acid. 
Essential  oils. 
Extractives. 
I  Mineral  matters,  015  to  06  per  cent. 

It  will  be  realized  from  this  what  a  very  complex  fluid  wine  is. 
•It  is  a  profound  mistake,'  says  Dujardin  Beaumetz,  *to  regard  wine 
as  a  mere  mixture  of  alcohol  and  water.  It  is  a  complete  living 
entity,  if  I  may  so  say,  of  which  all  the  elements  constitute  an 
ensemble  so  complex  and  homogeneous  that  we  cannot  modify  one 
or  another  without  producing  profound  changes  in  the  composition 
of  the  wine  itself.  .  .  .  Wine  has  its  youth,  its  maturity  and  its  old 
»  'What  is  Wine?'  {Popular  Science  Review,  1868,  vii.  354). 


376  FOOD  AND  DIETETICS 

age.  Some  vintages,  such  as  burgundy,  have  a  short  life,  and 
become  prematurely  old ;  others,  Hke  claret,  have  a  much  longer 
life,  and  are  even  sent  on  a  voyage  to  hasten  their  maturity.  Wines, 
too,  have  their  diseases — diseases  which  usually  result  from  imperfect 
manufacture  and  bad  fermentation,  leaving  in  them  impure  products.* 
The  amounts  of  the  chief  solid  constituents  in  i  litre  of  wine  are 
roughly  these  (Gautier^) : 

Water          718  to  935  parts 

Glycerine    ..          ..          ..         ..  4  ,,    10     ,, 

Colouring  matter  ..         ..         ..  06  ,,  1-5     ,, 

Tartrates i  ..  375  .. 

Total  solids            ..         ..         ..  14  ,,     90    ,, 

Ordinary  Rhine  and  French  wines  have  about  2  per  cent,  of 
solids  ;  port  has  about  5  per  cent.  It  would  serve  no  good  purpose, 
however,  to  give  an  analysis  of  wines  in  detail,  for,  after  all,  the 
information  which  chemistry  can  give  us  about  wines  is  of  limited 
value.  It  can  tell  us,  it  is  true,  a  good  deal  about  those  ingredients 
which  have  most  influence  upon  health,  but  it  cannot  tell  much 
about  those  volatile  compounds  to  which  the  most  highly-prized 
qualities  of  wine,  such  as  flavour  and  bouquet,  are  due,  and  for 
which  one  chiefly  pays  in  buying  wine  when,  indeed,  one  is  not 
merely  paying  for  the  label  on  the  bottle. 

I  propose,  therefore,  to  describe  briefly  the  most  important  of  the 
constituents  which  influence  health,  and  afterwards  to  consider 
the  chief  characters  of  some  of  the  commoner  wines  in  detail. 

I.  Alcohols. — Wine  contains  several  alcohols,  ethyl  alcohol,  how- 
ever, being  by  far  the  most  abundant.  Amyl,  propyl,  butyl,  and 
other  higher  alcohols  are  present  in  traces,  being  derived  chiefly  from 
fatty  substances  contained  in  the  skins  and  stones  of  the  grapes. 
A  hundred  volumes  of  a  natural  wine  may  contain  anything  from 
6  to  12  grammes  of  ethyl  alcohol.  If  there  be  less  than  this,  the 
wine  tastes  flat ;  if  there  be  more,  one  may  be  almost  quite  certain 
that  alcohol  has  been  added  artificially — i.e.,  that  the  wine  has  been 
*  fortified.'  The  advantage  of  fortifying  wine  is  that  it  enables  it  to 
keep  better,  subsequent  fermentation  being  restrained,  and  the  pro- 
duction of  acetic  acid  prevented.  It  is  often  necessary  in  the  case 
of  wines  produced  in  very  warm  countries,  where  fermentation  cannot 
safely  be  allowed  to  go  on  to  its  full  limits,  owing  to  the  danger  of 
the  growth  of  '  wild  '  yeasts  and  the  production  of  acids.  Fortified 
wines  not  unfrequently  have  as  much  as  one-third  of  their  volume  of 
spirit  added  to  them,  and  require  to  be  kept  for  a  long  time  in  bottle, 

*  '  La  Sophistication  des  Vins,'  1884. 


ACIDS  IN  WINE  377 

in  order  to  re-acquire  a  true  vinous  character.  Partial  sterilization 
of  the  wine  by  the  process  of  '  pasteurization  '  is  now  often  used  to 
effect  the  same  object  as  '  fortification.' 

2.  Acids. — The  natural  acids  found  in  wine  are  tartaric,  malic  and 
tannic.  Acetic,  formic,  succinic  and  other  fatty  acids  are  produced 
by  fermentation  along  with  carbonic  acid. 

Tartaric  and  tannic  acids  are  the  most  important.  The  former 
occurs  combined  with  potassium  in  the  form  of  bitartrate  of  potash 
or  argol.  As  the  proportion  of  alcohol  in  the  wine  rises,  the  bitartrate 
becomes  less  soluble,  and  ultimately  much  of  it  falls  out  in  the  form 
of  a  crust  of  '  tartar.'  Hence  it  is  that  wines  become  less  acid  on 
keeping.  The  form  of  tannic  acid  met  with  in  wine  is  probably  not 
identical  with  that  of  oak-bark.  It  is  chiefly  derived  from  the  skins 
and  stalks,  and  is  therefore  more  abundant  in  red  wines.  It 
diminishes  by  oxidation  on  keeping,  and  in  the  mature  wine  is  not 
present  in  any  large  amount ;  for  even  an  astringent  red  wine  has 
only  about  2  grains  in  a  2-ounce  glass,  while  an  ordinary  glass  of 
claret  (4  ounces)  has  not  more  than  i  to  2^  grains,  or  about  as  much 
as  is  contained  in  a  cup  of  tea. 

Acetic  acid  may  be  produced  in  wine  by  the  growth  in  the  *  must ' 
of  a  special  organism  (the  Mycoderma  aceti),  which,  if  unchecked, 
would  ultimately  convert  all  the  wine  into  vinegar.  It  flourishes 
especially  in  very  warm  countries,  and  the  necessity  for  preventing 
its  growth  is  one  of  the  reasons  why  the  wines  of  such  countries  are 
so  often  fortified. 

Acetic  acid  can  also  be  produced  by  direct  oxidation  of  the  alcohol 
of  wine  in  the  presence  of  albuminous  matter,  and  this  occurs  to 
some  extent  in  the  cask,  and  also  in  bottle,  if  any  air  finds  its  way 
into  the  wine  through  the  pores  of  the  cork.  In  order  to  prevent 
this,  the  bottle  should  always  be  laid  on  its  side,  so  that  the  cork  is 
kept  soaked  in  wine. 

In  a  sound  wine  the  total  acidity  is  not  more  than  0-3  to  0*7  per 
cent. ;  above  this  limit  the  wine  will  taste  sour.  It  must  be  noted, 
however,  that  mere  taste  is  no  true  indication  of  the  acidity  of  a  wine, 
for  the  sourness  is  much  concealed  by  the  presence  of  sugar.  As  a 
matter  of  fact,  many  sweet  wines  are  quite  as  acid  as  the  so-called 
sour  wines. 

Dupre  found  the  following  amount  of  acid  (reckoned  as  tartaric) 

in  one  bottle  of  wine  : 

Claret       ..         .. 65  to  77  grains 

Hock  .,         ..         ,.         ,,         ..  57, ,70     ,, 

Sherry 54  ,,  61      ,, 

Port  ..         ..          ..         .,         ..  49  ,,62      ,, 

Marsala  ..         ..         ..         ..         ••  39  ..46     .. 


378  FOOD  AND  DIETETICS 

A  sample  of  '47  port  analyzed  by  Luflf^  had  an  acidity  of  o*6  pet 
cent.,  equivalent  to  6  grains  of  tartaric  acid  in  every  wineglassful. 
He  calculates  that  three-fourths  of  the  total  acid  in  two  bottles  of 
such  wine  would  require  to  enter  the  circulation  at  one  time  in  order 
to  neutralize  the  alkalinity  of  the  blood. 

The  volatile  acids  in  wine  (acetic,  etc.)  should  not  be  present  in 
a  higher  ratio  than  i  to  3  of  fixed  acids  (tartaric).  If  the  propor- 
tion is  higher  than  this,  the  wine  is  slightly  '  turned  ' — i.e.,  is  on  its 
way  to  become  vinegar.  Red  wines  usually  contain  rather  more 
volatile  acid  than  white. 

3.  Sugar. — The  chief  sugar  found  in  wine  is  fruit-sugar,  or  laevu- 
lose.  A  *  natural '  or  fully-fermented  wine  should  contain  about 
^  per  cent,  of  sugar ;  if  there  is  less  than  this  the  flavour  is  not 
pleasant.  As  a  rule,  therefore,  natural  wines  are  '  dry.'  Sauteme 
is  one  of  the  few  natural  wines  which  is  rather  rich  in  sugar. 
*  Fortified '  wines  in  which  fermentation  has  been  checked  by  the 
addition  of  spirit  contain  2  per  cent,  of  sugar  or  more,  while  the 
sweet  wines  may  have  as  much  as  20  per  cent. 

Dupr6  found  the  following  amount  of  sugar  in  different  samples  of 

wine  : 

Hocks     ..  ..  1-410  8  6  grains  per  bottle. 

Clarets   ..  ..  ii   .,     18 

Sherries  ..  217  „  421 

Ports       ..  ..  121  ,,  519 

Old  marsala  ..  388  ,.  451 

Sauteme  ..  125 

Champagne  . .  500 

It  will  be  evident  from  this  that  sugar  can  hardly  ever  be  present 

in  wine  to  a  sufficient  extent  to  be  of  influence  as  a  food.     Even  a 

sweet   wine  with   4   per   cent,   of  sugar   will   contain   only  about 

an  ounce  in  a  bottle,  or  pretty  much  the  same  quantity  as  a  bottle 

of  ordinary  lemonade.     As  Ansti^  points  out,  it  is  hardly  possible  to 

take  in  more  than  ^  to  ^  ounce  of  sugar  daily  in  the  form  of  wine 

v,'ithout  at  the  same  time  consuming  so  much  alcohol  as  would 

produce  intoxication. 

4.  Ethers. — These  are  produced  by  the  interaction  of  the  alcohols 
and  acids  contained  in  the  wine.  They  are  very  numerous  as  regards 
variety,  as  can  readily  be  imagined  when  it  is  pointed  out  that  a  wine 
containing  five  different  kinds  of  alcohol  and  five  acids  may  contain 
twenty-five  ethers.  Their  actual  amount,  however,  is  always  very 
small.  The  highest  proportion  Dupre  found  was  in  a  fifty-year-old 
madeira,  and  even  then  there  was  only  i  part  of  ether  in  every 
300  of  wine. 

*  '  Goat :  its  P«tkology  and  Treatment,'  Cassell  asd  Co.,  1898,  p.  145  tt  isq. 


down  to  almost  none. 


ACIDS  IN  WINE  379 

The  ethers  uf  wine  may  be  divided  into  two  classes  :  (i)  volatile, 
(2)  fixed.  The  former  are  produced  by  volatile  acids,  such  as  acetic; 
the  latter  by  the  fixed  acids,  such  as  tartaric.  The  volatile  ethers 
predominate  in  natural  wines,  while  most  fortified  wines  contain  the 
fixed  ethers  in  greater  abundance.  To  this  rule,  however,  sherry 
and  madeira  seem  to  be  exceptions,  for  they  are  often  rich  in  the 
volatile  class. 

Acetic  ether  is  usually  the  most  abundant  volatile  ether  met  with 
in  wine,  but  old  wines  may  contain  traces  of  aceto-propylic,  aceto- 
butylic,  aceto-amylic,  aceto-caproic,  and  aceto-caprylic  ether  as 
well. 

The  ethers — and  especially  the  volatile  ones — are  of  importance  as 
imparting  to  wine  much  of  its  *  bouquet,'  and  a  rough  estimate  of 
their  richness  in  any  particular  wine  can  be  made  by  noting  the 
distance  at  which  the  bouquet  can  be  smelt.  They  also  contribute 
in  large  measure  to  some  of  the  most  important  therapeutic  pro- 
perties of  wine,  as  will  be  explained  later. 

The  substance  cenanthine,  or  oenanthic  ether,  demands  special 
mention.  It  is  derived  from  a  hypothetical  fatty  acid  (oenanthic 
acid)  contained  in  the  stones,  stalks,  and  skins  of  the  grapes,  and 
more  especially,  perhaps,  in  the  waxy  fat  which  gives  to  the  grapes 
their  bloom.  This  acid  is  not  found  by  itself  in  wine,  but  only  in 
the  combined  or  ethereal  form.  There  is  not  more  than  i  part  of 
it  in  every  40,000  of  wine,  but  along  with  glycerine  and  succinic  acid 
it  is  mainly  responsible  for  the  peculiar  '  vinous '  smell  and  taste 
characteristic  of  all  wines  in  common. 

5.  Extractives  usually  make  up  the  bulk  of  the  solid  matter  in  all 
wines,  except  such  as  are  rich  in  sugar.  They  consist  chiefly  of 
carbohydrates,  such  as  pectins  and  gums.  They  contribute  to  the 
taste  and  '  body  '  of  the  wine. 

6,  Glycerine  is  produced  along  with  alcohol  in  the  process  of 
fermentation,  and  is  always  present  in  wine  and  in  sufficient  amount 
to  affect  the  taste.  It  is  usually  said  that  it  amounts  to  one- 
fourteenth  of  the  volume  of  the  alcohol ;  but  that  is  not  quite 
a.  curate,  for  different  yeasts  seem  to  produce  it  in  varying  amount, 
so  that  no  definite  ratio  between  glycerine  and  alcohol  can  be  laid 
dcwn. 

Varieties  of  Wine. 

Perhaps  the  most  important  division  of  wines  is  into  (i)  natural 
and  (2)  fortified.  The  natural  wines,  as  already  explained,  are  those 
in  which  fermentation  has  been  allowed  to  go  to  its  full  limit — i\ut 


380  FOOD  AND  DIETETICS 

is  to  say,  until  the  process  is  arrested  spontaneously  either  by 
exhaustion  of  all  the  sugar  and  albuminous  matter  in  the  grape- 
juice,  or  until  suflEicient  alcohol  has  been  produced  to  prevent  the 
further  growth  of  the  yeast.  The  latter  consummation  is  reached 
when  the  fermenting  juice  contains  12  per  cent,  of  absolute  alcohol 
by  weight,  and  natural  wines,  as  defined  by  law,  must  contain  less 
than  that  amount.  Fortified  wines,  on  the  other  hand,  are  those  in 
which  the  process  of  fermentation  has  been  artificially  arrested  by 
the  addition  of  alcohoP  either  as  *  silent '  spirit,  brandy,  or  some 
other  concentrated  form.  Fermentation  being  thus  arrested  before 
all  the  sugar  has  been  broken  up,  such  wines  are  apt  to  be  sweet, 
and  are,  of  course,  of  comparatively  high  alcoholic  strength. 

Natural  wines,  on  the  contrary,  are  usually  poor  both  in  alcohol 
and  sugar.  The  natural  wines  also,  containing  as  they  do  a  little 
acetic  acid  produced  by  prolonged  fermentation,  are  rich  in  volatile 
ethers  even  in  their  youth,  while  the  fortified  wines,  though  they 
may  ultimately  contain  much  ether,  only  arrive  at  such  richness  in 
their  old  age,  and  the  fixed  ethers,  except  in  the  case  of  sherry  and 
madeira,  preponderate  over  the  volatile.  The  distinction  between 
natural  and  fortified  wines  is  of  further  importance  for  this  reason, 
that,  as  we  shall  see  later,  the  natural  wines  are  alone  suited  for 
habitual  consumption  as  articles  of  diet,  the  fortified  wines  being 
rather  to  be  regarded  as  medicinal  agents. 

The  principal  natural  wines  are  claret  and  hock,  and  the 
Hungarian,  Italian,  Australian,  and  Californian  wines.  The  chief 
members  of  the  '  fortified  *  group  are  port,  sherry,  madeira,  and 
marsala.  Champagne  and  the  Greek  wines  are  also  usually 
fortified. 

Claret  (probably  derived  from  clairet,  a  thin  vin  ordinaire)  is 
produced  in  the  district  of  Medoc,  the  seaport  of  which  is  Bordeaux. 
It  is  a  pure  natural  wine  containing  8  to  13  per  cent,  of  alcohol  by 
volume,  very  little  sugar  (about  ^  per  cent.),  and  a  moderate  amount 
of  acids,  acetic  acid  being  always  present  to  some  extent.  It 
contains  also  a  high  proportion  of  volatile  ethers.  The  best  growths, 
or  '  crus,'  are  Chateau  Margaux,  Lafitte,  and  Latour. 

Haut  Brion  is  a  red  wine  produced  in  the  neighbouring  district  of 
the  Gironde,  and  resembles  a  burgundy  rather  than  a  medoc. 
Sauternes  are  white  wines  made  in  the  same  district,  and  usually 
contain  a  good  deal  of  sugar,  from  the  grapes  being  allowed  to  hang 
for  a  long  time  on  the  vines  before  they  are  picked.     The  famous 

*  In  the  case  of  some  fortified  wines,  however,  e.g.,  sherry,  the  alcohol  is  added 
after  fermentation  is  complete. 


VARIETIES  OF  WINE  381 

Chiteau  Yquem  is  the  finest  of  all  the  white  wines  so  produced. 
Thudichum  states  that  brandy  is  sometimes  added  to  the  natural 
wines  of  Bordeaux  :  not  that  it  is  required  for  their  preservation,  but 
simply  in  order  to  suit  the  English  palate. 

Burgundy  resembles  claret,  but  is  richer  in  extractive  matter,  and 
has  therefore  more  •  body.'  It  is  also  of  higher  alcoholic  strength. 
It  is  produced  in  the  district  of  that  name,  the  best  part  being  that 
which  stretches  between  Dijon  and  Chalon.  The  most  esteemed 
varieties  are  Beaune  and  Chambertin.  Beaujolais  and  Macon,  though 
not  really  produced  in  Burgundy,  are  usually  classed  with  those 
wines.  Ordinary  burgundy  is  made  from  black  grapes,  but  Chablis 
is  a  white  burgundy  produced  from  white  grapes  grown  in  the  same 
district. 

Hocks  derive  their  name  from  Hochheimer,  on  the  right  bank  of 
the  Maine.  With  the  exception  of  that  produced  at  Assmanns- 
hausen,  they  are  all  pale  wines.  They  have  about  the  same  alcoholic 
strength  as  claret,  and  contain  hardly  any  sugar,  for  which  reason 
they  are  apt  to  seem  rather  acid.  Their  acidity,  however,  is  not 
much  higher  than  that  of  claret  (about  |  per  cent.),  and  they  contain 
almost  no  acetic  acid.  They  have  the  advantage  of  possessing  a 
fine  bouquet  and  extraordinary  keeping  qualities.  The  choicest 
varieties  are  those  of  Johannisberg,  Steinberg,  Marcobrvin,  Riides- 
heimer,  Rothenberg,  and  Hochheimer. 

Hungarian  wines  are  both  red  and  white,  and  rank  with  claret  and 
hock  as  the  finest  natural  wines  the  world  produces.  Their  alcoholic 
strength  is  about  the  same  as  that  of  the  other  two,  but  they  are 
rather  more  acid.  They  resemble  hock  in  being  almost  free  from 
sugar.  The  finest  variety,  Tokay,  is  produced  from  grapes  which 
have  been  allowed  to  dry  on  the  stalks  before  being  picked.  It  is  a 
sweet  wine  of  low  alcoholic  strength,  and  should  have  been  kept 
very  long  in  bottle.  The  special  Imperial  Tokay  is  one  of  the  choicest 
wines  known,  but  is  never  sold  in  trade.  Some  of  the  commoner 
dry  Hungarian  wines,  both  red  and  white,  make  excellent  table 
beverages.  They  have  rather  more  body  than  the  corresponding 
wines  of  France,  and  a  moderate  degree  of  astringency. 

Italian  wines,  both  white  and  red,  all  belong  to  the  *  natural ' 
class.  As  a  rule,  they  are  of  low  alcoholic  strength,  but  rather  more 
acid  and  astringent  than  a  light  Bordeaux  wine.  Their  acidity  is 
rather  high.  The  following  analyses  from  the  Lancei^  represent  the 
composition  of  some  of  the  varieties  more  commonly  sold  in  this 
coxmtry : 

»  1899,  i.  241. 


38a 


FOOD  AND  DIETETICS 


Capri 
(White). 

Falerno 
(WhiteX 

Chianti 
(Red). 

Barolo 
(Red). 

Egidio 

Vitali 

(Sparkling 

White). 

Valtellitit 
(Red). 

Alcohol  by  weight 
,,    volume 
Tartaric  acid 
Acetic        ,, 
Sugar 

11-62 

14-37 
0-52 
031 
076 

864 

1073 
066 
013 
O'll 

936 
II-6I 
060 
0  18 
017 

1085 

1343 

045 

0  25 

o-i8 

1008 
12-49 

079 

026 

367 

9-36 
ii-6i 
o'4i 
029 
013 

Californian  wines,  from  a  merely  chemical  point  of  view,  compare 
very  favourably  with  the  corresponding  wines  of  Europe,  though 
they  are  undoubtedly  not  yet  equal  to  the  latter  in  the  more  aesthetic 
qualities.  For  natural  wines,  they  contain  rather  a  high  proportion 
of  alcohol,  but  relatively  little  glycerine.  In  the  white  varieties  the 
extract,  total  acidity  and  ash  are  generally  lower  than  in  the  corre- 
sponding European  wines,  while  in  the  red  sorts  these  ingredients 
are  relatively  higher  than  in  the  old-world  wines.  A  careful  inves- 
tigation of  them  has  been  made  by  Krug,i  who  concludes  as  follows ; 
'  On  the  whole,  it  is  evident  that  the  Californian  dry  wines  are  fully 
equal  to  the  European  wines,  and  the  red  wines  are  in  every  respect 
superior  to  the  young  French  clarets.  The  sweet  wines  are  to  be 
unconditionally  preferred  to  the  European  Southern  wines,  containing 
the  same  amount  of  alcohol  and  extract,  and  not  being  plastered.' 
Their  chemical  equality  with  European  wines  is  also  confirmed  by 
the  Lancet,^  from  which  the  following  analyses  are  taken  : 


A  Californian 

A 

Californian 

Saute  me. 

Hock. 

Per  cent. 

Per  ce7tt. 

Alcohol  by  weight 

..     10-31 

1000 

,,       ,,     volume        1 

..     12-77 

12-40 

Extract 

..       2-31 

I -go 

Ash 

,,       0-16 

0-20 

Total  acids 

0-69 

0-67 

The  Australian  wines  resemble  rather  closely  those  of  California, 
They  are  full-bodied  natural  wines,  containing  rather  more  alcohol 
than  most  clarets.  They  are  chemically  pure,  and  in  recent  years 
have  improved  very  much  in  the  finer  characteristics  of  good  wine, 
as  the  result  of  greater  care  in  the  cultivation  of  the  grape. 

The  term  sherry  is  applied  to  all  the  white  wines  of  Spain,  being 
derived  from  the  town  of  Jerez,  which  may  be  regarded  as  the 
capital  of  the  sherry-producing  district.  As  drunk  in  this  country, 
they  are  all  fortified  wines,  containing  from  15  to  22  per  cent,  of 
alcohol  by  weight.  A  *  natural  '  sherry  is  quite  a  possible  product, 
but  is  never  imported  into   this  country  on   account  of  its  being 

»  Journ.  of  Amn.  Chem.  Soc,  1894,  xvi.  597.  '  1894,  ii.  30- 


CHARACTERS  OF  DIFFERENT  WINES  383 

deficient  in  'keeping'  qualities.  Sherries  are  also  all  'plastered' 
wines  ;  that  is  to  say,  sulphate  of  lime  is  sprinkled  on  the  grapes 
after  they  are  first  trodden,  in  the  proportion  usually  of  2J  pounds 
to  every  ton. 

The  practice  of  plastering  is  one  of  great  antiquity,  and  was 
mentioned  long  ago  by  Pliny.  It  was  first  adopted,  no  doubt, 
empirically,  and  the  advantages  of  it  are  still  far  from  being  fully 
understood,  although  all  experienced  sherry-growers  are  of  opinion 
that  without  its  aid  the  production  of  a  wine  having  the  special 
characteristics  of  sherry  is  impossible.  It  may  be  that  it  acts  as 
a  preservative  against  the  '  viscosity  fungus,'  which  is  so  much 
commoner  in  Southern  than  Northern  wines  (Thudichum). 

The  chief  chemical  effect  of  plastering  is  to  decompose  the  bi- 
tartrate  of  potash  in  the  '  must '  with  the  production  of  insoluble 
tartrate  of  lime,  sulphate  of  potash,  and  tartaric  acid,  according  to  the 
following  equation  : 

aKHC^H^O,  +  CaSO<= K,S04  +  CaC^Hp,  +  H.^C^Hp,. 

The  phosphates  are  also  thrown  down. 

As  the  tartrate  of  calcium  falls  out,  it  clarifies  the  wine,  carrying 
down  with  it  albuminous  matters  and  suspended  impurities.  The 
tartaric  acid  produced  renders  the  wine  redder,  and  increases  its  free 
acidity,  so  facilitating  the  production  of  ethers  later  on. 

There  is  introduced  into  tlie  wine  as  the  result  of  plastering 
0-3  gramme  of  sulphate  of  calcium  per  litre,  and  1-2  grammes  of 
sulphate  of  potash,  much  of  it,  probably,  in  the  acid  form.  The 
sulphate  of  potash  may  cause  sherry  to  be  slightly  laxative  to  some 
persons  if  freely  drunk,  and  renders  it  also  somewhat  bitter,  but  it 
cannot  be  said  to  have  any  other  bad  effects.  It  has  been  said  that 
it  may  be  productive  of  cirrhosis,  but  of  this  there  is  no  suflficient 
evidence,  and,  indeed,  the  employes  in  the  Spanish  bodegas  are 
stated  to  drink  as  much  as  io|  pints  of  light  sherry  daily,  without 
suffering  from  any  injurious  effects. 

The  amount  of  sugar  in  sherry  varies  from  practically  nil  in  the 
driest  sorts  up  to  4  per  cent,  in  a  very  raisiny  wine.  The  acidity  is 
lower  than  that  of  the  natural  wines  already  considered. 

Sherry  develops  in  its  old  age  a  very  large  proportion  of  volatile 
ethers — more,  probably,  than  any  other  alcoholic  liquor,  except  a 
genuine  cognac.  To  this  property  much  of  its  value  as  a  stimulant 
in  disease  is  to  be  attributed. 

Broadly  speaking,  there  are  two  classes  of  sherries : 


384  FOOD  AND  DIETETICS 

1.  *  Fino,'  a  light,  pale,  delicate  wine  of  Amontillado^  or 
Manzanilla^  type. 

2.  '  Oloroso,'  a  sweeter,  full-bodied,  brown  wine.  Intermediate 
between  these  is  the  class  known  as  '  Palo  Cortado.' 

The  following  is  an  analysis  of  examples  of  these  :' 

Amontillado.  Oloroso.  Medium. 

Per  cent.  Per  cent.  Per  cent. 

Solids 220  545                  287 

Sugar      ..         ..         ..       0-215  103                  065 

Potassium  bitartiate    ..       008  026                  0-13 

Tartaric  acid      ..         ..       034  052                  0-41 

Acetic        ,,         ..          ..       012  020                  010 

Ash          ..          ..          ..       055  o  85                  070 

Sulphate  of  potash       ..       032  076                 065 

Alcohol  by  weight        ..     1482  18-85                ^5'^7 

,,       ,,     volume        ..     1825  23-10                 19-28 

Total  ethers       ..         ..       006  021  0075 

Pure  sherry  may  be  regarded  as  a  genuine  grape  product,  for  the 
substances  added  to  it  in  manufacture  are  also  derived  from  grapes. 
Thus,  *  grape  liquor  *  is  used  for  sweetening,  and  the  same,  shghtly 
caramelized,  for  colouring.  The  spirit  added  in  fortification  is  also 
obtained  by  distilling  fermented  grape-juice. 

Port  is  the  wine  produced  in  the  district  of  the  Upper  Douro,  and 
takes  its  name  from  the  town  of  Oporto.  The  whole  of  the  wine 
that  reaches  this  country  is  fortified,  containing  from  15  to  20  per 
cent,  of  alcohol  by  weight.  One  of  the  chief  peculiarities  of  port  is 
the  large  amount  of  '  extract '  it  contains,  which  gives  it  a  full  body. 
Its  acidity  is  not  great,  less,  indeed,  than  that  of  hock,  but  it  contains 
I  datively  more  acetic  than  tartaric  acid,  for  the  latter  is  insoluble  in 
the  large  amount  of  alcohol  which  port  holds.  It  possesses  a  good 
deal  of  tannic  acid,  the  stalks  not  being  removed  before  fermentation, 
but  this  diminishes  with  age,  though  when  young  it  is  very  rough 
and  astringent.  It  is  sweeter  than  sherry,  containing  from  2  to  6 
per  cent,  of  sugar,  for  it  is  fortified  before  fermentation  is  complete, 
not  after  it,  as  sherry  is.  Old  port  contains  a  large  proportion  of 
ethers,  but,  unlike  sherry,  the  fixed  ethers  predominate  over  the 
volatile.  When  mellowed  it  has  an  excellent  flavour  and  bouquet, 
and  retains  only  a  moderate  amount  of  fruitiness. 

Madeira  is  derived  from  the  island  of  that  name.  For  a  long  time 
the  ravages  of  the  phylloxera  stopped  the  production  of  the  wine, 
but  in  recent  years  the  industry  has  begun  to  revive.  The  wine 
resembles  sherry  in  its  general  characteristics  and  in  the  high  pro- 

'  Amontillado  =  a  la  Mantilla  (a  town  near  Cordova). 
'  From  Manzanilla,  a  town  near  Jerez. 

*  Lancet,  1898,  ii.  1135  (Report  of  Commission  on  Sherry,  from  which  many  of 
*ha  statements  in  the  above  paragraphs  are  taken). 


MARSALA  AND  CHAMPAGNE  385 

portion  of  volatile  ethers  which  it  contains.     It  is  a  fortified  wine, 
containing  from  17  to  20  per  cent,  of  alcohol  by  weight. 

Marsala  is  a  Sicilian  wine  also  resembling  sherry,  but  sweeter  and 
containing  a  much  lower  proportion  of  volatile  ethers.  It  is  only 
slightly  acid. 

Greek  wines  may  be  either  natural  or  fortified,  but  usually  contain 
only  8  to  14  per  cent,  of  alcohol  by  weight.  They  are  rich  in 
volatile  acids,  and  are  peculiar,  also,  in  containing  some  aldehyde. 
They  are  often  plastered.  Their  chief  defects  are  due  to  imperfec- 
tions in  the  methods  of  manufacture. 

Champagne  is  the  wine  produced  in  the  Champagne  district  of 
France,  the  best  varieties  being  obtained  from  the  prefectures  of 
Rheims  and  Epernay.  It  is  produced,  curiously  enough,  chiefly 
from  black  grapes.  These  are  squeezed  in  a  very  powerful  press, 
and  the  first  pressings  used  to  produce  the  finest  wines.  The 
character  of  the  vintage  in  different  years  has  also  a  very  marked 
effect  on  the  quality.  The  expressed  juice,  or  *  must,'  is  allowed  to 
stand  for  twelve  hours  in  order  to  let  all  suspended  matters  fall  out, 
and  is  then  drawn  off  into  casks  to  undergo  the  first  fermentation. 
At  this  stage  the  different  growths,  or  '  crus,'  are  blended  to  form  the 
special  *  cuvees,'  the  finest  of  which  are  only  produced  from  the  best 
grapes.  The  young  wine  is  then  bottled  and  left  for  two  years,  to 
undergo  the  secondary  fermentation.  The  maintenance  of  a 
constant  temperature  is  very  important  at  this  stage,  and  is  attained 
at  Chalons,  Epernay,  and  Rheims,  by  storing  the  bottles  in  large 
cellars  excavated  from  chalk  cliffs.  During  this  fermentation  a 
large  amount  of  carbonic  acid  gas  is  produced,  and  as  the  percentage 
of  alcohol  rises  a  considerable  deposit  falls  down  into  the  neck  of  the 
inclined  bottle.  This  is  fixed  to  the  cork  by  freezing,  and  removed 
with  the  latter  in  the  process  of  •  degorgement.'  The  wine  is  still  of 
a  sour,  harsh,  or  *  brut '  character,  and  is  made  drinkable  by  '  dosage.' 
This  consists  in  adding  to  it  a  solution  of  cane-sugar^  dissolved  in  old 
champagne  and  good  cognac.  Upon  the  amount  of  dosage  the 
sweetness  or  dryness  of  the  wine  depends.  In  this  country  we  like 
champagne  dry,  and  therefore  only  2  to  4  per  cent,  of  liqueiu:  is 
added  to  the  wine  exported  to  England.  For  Russia,  where  a  sweet 
wine  is  preferred,  as  much  as  14,  or  even  16,  per  cent,  of  liqueur  is 
used.  The  wines  exported  to  the  United  States,  Belgium  and 
Germany  receive  an  intermediate  degree  of  treatment.  There  can 
be  no  doubt  that  the  taste  for  a  dry  champagne  is  rewarded  by 

^  The  cane-sugar  is  gradually  changed  into  invert  sugar  after  it«  addition  to  the 
wiae. 

»5 


386 


FOOD  AND  DIETETICS 


getting  a  purer  wine,  for  heavy  liqueuring  covers  many  defects. 
Hence  the  dry  wines  are  really  the  finest.  It  must  be  remembered, 
however,  that  unless  8  per  cent,  of  liqueur  has  been  added  the 
quality  of  the  wine  will  not  be  found  to  improve  after  longer  than 
twenty  years. 

Champagne  should,  strictly  speaking,  be  a  natural  wine,  con- 
taining from  9  to  12  per  cent,  of  alcohol  by  weight,  but  in  recent 
years  a  taste  for  a  stronger  wine  has  grown  up,  and  champagne  as 
drunk  in  England  is  now  mostly  a  brandied  liquid  (Thudichum). 
The  amount  of  sugar  varies  from  nil  up  to  14  per  cent.,  depending 
on  the  dosage.  The  acidity  is  about  0-5  to  0*6  per  cent. — i.e.,  that 
of  an  average  claret.  A  dry  champagne  contains  about  2  per  cent. 
of  solid  matter.  A  bottle  of  good  champagne  will  contain  about 
five  volumes  of  carbonic  acid  gas.  Four-fifths  of  this,  however,  is 
given  off  as  soon  as  the  cork  is  drawn. 

The  following  table  from  Dupre's  analyses  may  be  of  use  for  the 
purpose  of  comparing  the  chemical  composition  of  some  of  the  wines 
just  described.  It  must  be  remembered,  however,  that  mere 
chemical  analysis  is  only  of  limited  use  in  judging  of  the  quality  of 
a  wine  : 


Grammes 

Free 

Free 

Total 
Acid. 

Dry 

Total 

Alcohol 

Wine. 

Absolute 

Fixed 

Volatile 

Sugar. 

Resi- 

Ash. 

Alcohol. 

AciJ. 

Acid. 

due. 

Ethers. 

Hock   (three 

samples) 

973 

0-399 

0088 

0-506 

0062 

1-92 

0-17 

0-042 

Claret    (three 

samples) 

968 

0390 

0-167 

0-599 

0243 

2-124 

0-21 

0-038 

Hungarian 

wine      (three 

samples) 

1016 

0-454 

0-192 

0  694 

0077 

I  906 

o-i8 

0046 

Greek   wine 

(three  samples) 

12-35 

0342 

0-215 

0611 

0225 

2507 

030 

0-048 

Sherry      (three 

samples) 

17-80 

0-286 

0161 

0-487 

3015 

506 

0-50 

0061 

Madeira    (two 

samples) 

17-82 

^  373 

0-247 

0680 

185 

444 

037 

0  096 

Port    (three 

samples) 

i8-ii 

0309 

009 

0434 

2-54 

534 

0-23 

0053 

Marsala     (two 

samples) 

i68 

0206 

0-I2 

o'36i 

3-50 

536 

0-26 

0049 

The  table  gives  weights  of  different  ingredients  in  100  c.c.    To  get  grains  per 
bottle  multiply  by  120. 


COMPARATIVE  COMPOSITION  OF  WINE 
The  following  more  recent  analyses^  may  also  be  given : 


387 


THE   COMPARATIVE   COMPOSITION    OF    DIFFERENT   VARIETIES 

OF  WINE. 


Wine. 


A.  French  Clarets  : 

Ch.  Margaux  .. 

Ch.  Haute  Lafite     . . 

Bordeaux 

Medoc 

Ch.  Margaux 

Ch.  Larose    . . 

Ch.  Brane-Cantenac 

Ch.  d'Issan   . .         .. 

Sweet  Sauternes 

Dry  Sauternes  . . 

Haut  Graves 

Graves  .«         .. 

B.  Moselles  : 

Moselle  (i)     ..  .« 

Schwarzberger  .. 
Moselle  A. 

Moselle  '93    . .  .. 

Moselle  W.    . ,  ., 

Brauneberger  ,, 

C.  Hocks : 

Hock  I 

•.  3 
..  4 
..     5 

D.  Champagnes  : 

Champagne,  i  .. 

•1  2 

3 
4 

E.  A  ustralian  : 

Australia.i,  i  ., 

2 
3 

M  4 

5 
6 

7 
8 

F.  Spanish,  i         ,,         ,, 

G.  Italian,    i         ,.         .. 


Alcohol. 

Extract. 

Acid. 

Volume 

Grammes 

Grammes 

Per  Cent. 

per  Litre. 

per  Litre. 

12-68 

25-35 

2-92 

12-48 

27-10 

3-28 

10-70 

27-24 

3-48 

10-25 

23-39 

3-16 

n-6o 

2999 

3-30 

lOOI 

24-09 

3-28 

11-68 

2344 

3  02 

9-91 

20  80 

2-76 

11-68 

36-12 

3-97 

1278 

29-87 

4-06 

I2*00 

28-34 

456 

12 '27 

34-16 

4*99 

9-91 

20-07 

4-25 

11*14 

21-60 

4-07 

10-66 

2026 

4-23 

11-41 

22-28 

4-51 

9-23 

18-31 

3-63 

11-67 

2099 

3-63 

II '41 

1906 

2-98 

923 

25-84 

3-49 

974 

23-52 

2-80 

10-89 

5977 

630 

976 

22-36 

4-02 

13-70 

3570 

4-02 

13-90 

35-n 

4-21 

13-48 

35-20 

4-12 

io-6i 

71-16 

4-96 

14-20 

29-65 

2-96 

16-19 

36-68 

2-98 

13-39 

29-15 

4-05 

13-16 

25-04 

330 

1448 

37-40 

4-17 

13-25 

28-46 

3-97 

15-46 

88-27 

421 

15-36 

3024 

4-02 

13-60 

33-66 

3-63 

10-79 

22-90 

363 

Sugar. 

Grammes 
per  Litre. 


I -08 

0-92 
140 
3-0 
2-7 
40 


1-35 
1  51 


30-00 
1-51 


19-2 
18-4 
156 
55-0 


2-84 
1-08 
0-92 
2-57 
1-63 
50-00 

2-57 
8-08 
i-oo 


Cider  and  Perry,  derived  from  the  apple  and  pear  respectively, 
may  be  conveniently   considered   here,  for  they   are  really  to   be 

1  Report  of  the  Hospital's  Commission  on  Light  Wines  {The  Hospiiul.    1907, 
xlii.  285). 


388  FOOD  AND  DIETETICS 

regarded  as  wines ;  cider,  indeed,  when  first  made  in  England  in 
the  thirteenth  century  was  always  called  *  wine.' 

The  finest  English  cider  is  made  in  Devon,  Hereford  and  Somerset. 
The  mid-season  fruit,  which  ripens  in  October,  is  best  for  the 
purpose.  It  is  gathered  and  allowed  to  mellow  under  cover  for  a 
fortnight,  and  is  then  ground  to  a  pulp,  the  kernels  being  sometimes 
left  out.  The  pulp  is  left  in  vats  for  thirty  hours,  and  is  then 
pressed,  and  loo  gallons  of  the  liquor  run  into  a  clean  vat  and  left 
for  some  days  till  it  clears.  It  is  then  racked,  clarified  with  charcoal 
and  strained  through  bags,  and  the  clear,  bright  liquid  run  into 
loo-gallon  casks  and  bunged  down.i  Perry  is  made  in  a  very 
similar  way.  If  a  *  sparkling '  beverage  is  desired,  fermentation  is 
allowed  to  go  on  in  bottle.  The  composition  of  these  beverages 
seems  to  vary  within  rather  wide  limits.  They  are  only  mildly 
alcoholic,  having  3  to  8  per  cent,  by  volume,  or  much  the  same 
proportion  as  beer.  Sugar  amounts  to  0*2  to  o-6  per  cent.  They 
are  moderately  acid  (o*i  to  o-6  per  cent.),  the  chief  acid  present 
being  malic.  The  more  acid  varieties  (o-6  per  cent.)  will  have  an 
acidity  equal  to  about  22  grains  of  tartaric  acid  per  tumblerful. 

A  sample  of  genuine  Devonshire  home-made  cider  which  I 
examined  had  the  following  composition  : 

Alcohol  (by  volume)  60    percent. 

Solids              ..         ..  ..         ..         ..  i'5           „ 

Total  acidity            ..  ..         ..         ..  066        „ 

Volatile  acidity        ..  ..         ..         ..  ooSg      „ 

The  following  analyses  are  from  the  Lancet  :• 

Cider  Champagns 

^^'^'-  Perry. 

Alcohol  by  weight     ••        ••        •.    270  1-45 

„      volume           ••        ••    340  i'8o 

Solids ••         ..     816  ii-o 

Ash 032  0-35 

French  and  American  imported  ciders  are  thinner  and  weaker  than 
the  home-made  article.  Bottled  cider  has  less  alcohol  (3  to  4  per 
cent.)  and  more  sugar  (2|  to  6  per  cent.)  than  draught.^ 

Medicated  wines  are  concoctions,  the  basis  of  which  is  port  or 
sherry,  to  which  has  been  added  extract  of  beef,  extract  of  malt, 
peptone,  pepsin,  coca  leaves,  cocaine,  cinchona,  iron,  or  some  other 
dietetic  or  medicinal  substance.  A  '  beef  and  malt  wine  *  may 
usually  be  regarded  as  containing  about  i^  ounces  of  extract  of  meat 

1  Radcliffe  Cooke, /o«n».  of  the  Soc.  oj  Arts,  1895,  xliii.  396. 

^  October  i,  1892. 

»  Felix  Aury,  *  Le  Cidre  et  le  Poire,'  These  de  Paris,  1894. 


MEDICATED   WINES 


389 


and  2  ounces  of  malt  extract  in  a  pint  of  *  detannated '  port  or 
sherry.^  For  the  medicinal  wines  there  is  no  definite  formula.  Of 
the  '  coca  '  wines,  some  are  made  from  coca  leaves,  others  from  liquid 
extract  of  coca,  and  some  from  hydrochlorate  of  cocaine. 

The  following  table  ^  shows  the  proportions  of  the  chief  ingredients 
present  in  some  of  these  wines,  the  composition  of  the  ordinary 
standard  wines  being  given  for  comparison  : 


Meat  Extract 

Wine. 

Alcohol  by 
Volume. 

Sugar  by 

Weight. 

by  Weight, 

corresponding 

to  Nitrogen 

Found. 

Pure  Alcohol 
in  a  Wine- 
glassful. 

Per  Cent. 

Per  Cent. 

Per  Cent. 

Fluid  Drachms. 

Claret 

9 

0-25 

— 

li 

Hock        

10 

Trace 

— 

n 

Champagne  (dry) 

10  to  15 

Trace  to  2 

— 

ij  to  2 

Sherry  (dry) 

(brown) 

18 
23 

o-2\ 
i-o/ 

— 

3t0  3i 

Port         

20 

2  to  6 

— 

3i 

Bovril  Wine      .. 

2015 

10  2 

05 

3i 

Lemco  Wine 

17-26 

128 

06 

2V 

Wincarnis          ..         ,. 

196 

i8-2 

12 

Glendenning's  .. 

20-8 

106 

04 

Bendle's    Meat    Port 

Nutrient^ 

20*3 

8-0 

2-5 

3i 

F.ivo         

19-2 

"•5 

3-4 

3 

Vin  Regno         ..         .. 

16-05 

7-4 

03 

2i 

The  use  of  these  wines  can  on  no  grounds  be  recommended.  In 
the  first  place,  they  are  not  worth  the  price  charged  for  them,  for  it 
is  far  cheaper  and  also  better  for  an  invalid  to  get  beef  or  malt 
extract  separately  and  take  along  with  them,  if  need  be,  a  definite 
quantity  of  sound  wine  of  known  antecedents.*  In  the  second  place, 
it  is  open  to  grave  question  whether  the  ferment  of  malt  (diastase) 
is  not  much  impaired  by  the  action  of  the  alcohol  to  which  it  is 
exposed  when  dissolved  in  a  fortified  wine,  such  as  port  or  sherry. 

The  medicated  wines  are  open  to  the  same  objection  to  an  even 
greater  extent.  The  use  of  such  liquors  by  an  invalid  on  his  own 
responsibility,  or  even  by  prescription,  exposes  him  to  great  danger 
of  becoming  by  degrees  the  unconscious  victim  of  alcoholism,  and, 
in  the  case  of  the  coca  wines,  of  the  cocaine  habit  as  well.  On 
every  ground  their  manufacture  and  sale  should  be  strongly  depre- 
cated by  the  medical  profession.     (See  also  p.  565,  footnote.) 

1  The  quantity  of  bouillon  represented  by  a  wineglassful  of  such  a  wine  varies 
from  about  4  tablespoonfuls  to  i|  teaspoonfuls  {Brit.  Med.Jotirn.,  1909,  i.  795). 

-  Brit.  Med.  Journ.,  1909.  i.  795. 

^  Meat  Port  Nutrient  is  peculiar  in  containing  about  ij  to  3  per  cent,  of 
uncoagulated  proteid  of  beef-juice  (Lancet,  1908,  ii.  242). 

*  See  also  Coley,  Brit.  Mai,.  Jpurn,,  1898,  iJ.  715. 


390  FOOD  AND  DIETETICS 

Non-Alcoholic  Grape  Wines  are  now  made  which  consist  of  pure 
grape  juice  preserved  by  pasteurization  ('  Mostelle,'  '  Vindevie,' 
'Salvator  Brand,'  etc.).  Suitably  diluted,  they  form  pleasant  and 
refreshing  drinks,  useful  for  quenching  thirst  in  fever  and  possessed 
of  slight  laxative  and  diuretic  properties.^ 

Action  and  Uses  of  Wines. 
Influence    on    Digestion. — Wines    have   a  much    more    powerful 
inhibitory  effect  on  salivary  digestion  than  mixtures  of  alcoliol  and 
water  of  similar  strength.     Roberts,^  for  example,  found  that  if  even 

1  per  cent,  of  sherry  or  hock  were  present  in  the  digesting  mixture, 
the  conversion  of  starch  was  almost  brought  to  a  standstill.  This 
effect  of  wines  is  entirely  due  to  their  acidity.  The  experiments  of 
Aitchison  Robertson^  showed  that  a  claret  of  075  per  cent,  acidity 
had  a  markedly  retarding  effect  on  salivary  digestion,  while  the 
influence  of  a  sherry  of  0*54  per  cent,  and  a  port  of  0*42  per  cent, 
was  very  much  less.  Chittenden  and  Mendel  confirmed  these  results. 
The  inhibitory  effect  of  wines  is  lost  when  their  acidity  is  neutralized. 
Hence,  it  is  an  obvious  advantage,  from  a  digestive  point  of  view,  to 
mix  the  more  acid  wines  with  an  alkaline  aerated  water. 

On  gastric  digestion,  also,  wines  exert  a  retarding  effect  out  of  all 
proportion  to  the  amount  of  alcohol  they  contain.  The  cause  of  this 
is  not  clear.  According  to  some  writers,  it  depends  upon  their  solid 
ingredients.  Roberts  attributes  it,  in  part  at  least,  to  some  of  the 
volatile  constituents.  Sherry  and  port  seem  to  have  a  more 
powerful   effect   than   claret   or   hock.     Half   a   pint    of  sherry   in 

2  pounds  weight  of  stomach  contents  is  sufficient  to  produce  a  very 
pronounced  degree  of  inhibition,  and  yet  this  is  a  not  infrequent 
allowance.  A  pint  of  claret  or  hock  is  also  enough  to  produce 
distinct  effects.  Efferve?cing  wines,  on  the  other  hand,  such  as 
champagne,  are  much  more  feeble  in  their  results,  probably  because 
the  gas  which  escapes  from  them  churns  up  the  contents  of  the 
stomach  mechanically. 

'  The  effect  of  wines  on  pancreatic  digestion  is  akin  to  their  action  in 
the  mouth,  and  may  be  entirely  explained  by  their  acid  qualities ' 
(Chittenden). 

It  must  be  remembered  that  the  above  remarks  apply  only  to  the 
effects  of  wines  upon  the  chemical  processes  of  digestion.*  As  in  the 
case  of  alcohol,  it  by  no  means  follows  that  the  net  result  of  taking 
wine  with  meals  is  unfavourable  ;  for,  by  the  increase  of  appetite 

^  For  analyses  see  the  Lancet,  1903,  ii.  761.  They  are  supplied  by  Rein- 
heimer  and  Co.,  Surbiton,  Surrey;  J.  Rabourdin,  i,  East  India  Avenue,  E.G.  ; 
Schweppes,  Ltd.,  and  others. 

'  '  l)igestion  and  Diet,'  p.  117. 

*  Joiirn.  of  Anat.  and  Physiolug.,  1898,  xxxii.  O15. 

*  Tlie  conclusion  drawn  from  experiments  made  by  a  Special  Commission  ou 
light  vviues  {Fhc:  lloipital,  J 907,  xlii.  285)  is  that  such  wines,  in  quantities  of  from 
&  to  10  ounces,  are  '  in  do  sense  immiaaX  to  digestion.' 


ACTION  OF  WINES  IN  HEALTH  391 

and  gastric  secretion  which  they  induce,  they  may,  in  moderate 
quantity  at  least,  not  only  neutralize  any  inhibition  of  the  merely 
chemical  processes  which  they  exert,  but  actually  render  digestion 
quicker  and  easier  than  it  otherwise  would  be.  This,  indeed,  is  one 
of  the  most  useful  actions  of  wines  both  in  health  and  disease. 

General  Action  of  Wines  in  Health. — '  The  conventional  value  of 
wine  is  determined  less  by  its  principal  ingredients  than  by  the 
prominence  of  the  specific  character  termed  bouquet  and  the  absence 
of  certain  faults.  Dietetically,  most  wines  are  of  equal  value  pro- 
vided they  are  the  products  of  a  favourable  season,  pure  and  free 
from  the  faults  produced  by  fungi '  (Thudichum). 

'  I  have  purposely  made  no  attempt  to  answer  the  question  so 
frequently  and  so  uselessly  put,  "  Why  is  one  kind  of  wine  better 
than  another  ?"  Every  constituent  helps  to  promote  excellence  : 
alcoholic  content,  bouquet,  and  every  non-volatile  ingredient.  One 
wine  is  liked  on  account  of  its  aroma,  another  on  account  of  its 
strength,  a  third  simply  because  of  its  flavour  '  (Mulder). 

These  two  quotations  contain  the  gist  of  most  that  can  be  said  as 
to  the  action  of  different  wines  on  the  human  body.  •  Nevertheless, 
they  do  not  embrace  quite  the  whole  truth.  We  may  admit  that, 
for  the  purposes  of  dietetics,  most  sound  wines  are  equally  good  as 
long  as  their  alcoholic  strength  is  the  same,  and  that  the  aesthetic 
qualities  determine  their  market  much  more  than  their  hygienic 
value ;  but  it  must  be  remembered  that  a  wine  may  contain 
ingredients  which  elude  chemical  analysis,  but  which  are  yet  not 
without  influence  upon  health,  for,  as  has  been  truly  said,  '  the 
human  brain  and  the  human  stomach  are  the  only  analysts  which 
never  makes  mistakes.' 

The  subject  is  further  complicated  by  the  fact  that  different 
constitutions  react  very  differently  to  the  same  wine,  a  fact  which 
must  be  within  the  experience  of  everyone.  To  some  extent  this 
may  be  explained  by  difference  of  habits,  the  sedentary  man,  for 
example,  requiring  to  be  much  more  sparing  in  his  use  of  certain 
wines  than  his  fellow  of  more  active  pursuits ;  but  this  does  not 
account  for  all  the  facts,  and  much  must  be  put  down  to  what,  for 
want  of  a  better  name,  one  can  merely  describe  as  idiosyncrasy. 

In  endeavouring  to  get  further  light  on  the  subject,  we  shall  do 
best  to  consider  the  effects  of  the  principal  constituents  of  wanes  on 
the  body  individually,  and  afterwards  attempt  to  deduce  from  the 
results  of  that  study  some  general  rules  for  our  guidance  in  recom- 
mending wines  in  health  and  disease. 

Alcohol. — As  a  general  rule,  the  stimulating  action  of  any  wine 


39%  FOOD  AND  DIETETICS 

depends  chiefly  upon  the  amount  of  alcohol  which  it  contains. 
Now,  the  natural  wines  only  contain  about  half  as  much  alcohol  as 
the  strong  or  fortified  wines,  so  that  two  bottles  of  good  claret  or 
hock  are  about  equal,  as  far  as  alcohol  is  concerned,  to  one  bottle  of 
port  or  sherry. 

Roughly  speaking,  then,  the  stimulating  action  of  a  fortified  wine 
may  be  regarded  as  twice  as  great  as  that  of  a  natural  wine.  This, 
however,  is  not  necessarily  quite  true  in  any  given  case.  Wines 
cannot  be  regarded  as  mere  mixtures  of  alcohol  and  water  in 
different  proportions.  For  one  thing,  the  mere  fact  of  dilution  is  of 
importance.  The  more  dilute  the  alcohol  is,  the  more  slowly  it  will 
be  absorbed,  and  the  less  the  chance  of  a  large  quantity  of  it  reach- 
ing the  tissues  at  one  moment.  The  ethers  and  other  volatile  con- 
stituents, too,  have  a  certain  modifying  influence  upon  some  of  the 
actions  of  alcohol,  and  a  wine  which  is  rich  in  these  elements  may 
be  expected  to  have  a  different  effect  from  another  which  is  devoid 
of  them,  even  although  the  two  are  of  equal  alcoholic  potency. 
Notwithstanding  this,  and  when  all  due  weight  has  been  given  to 
such  modifying  factors,  one  is  pretty  safe  in  concluding  that  it  is 
only  the  weaker,  i.e.,  natural,  wines  which  are  adapted  for  habitual 
use  as  accessories  of  the  diet.  We  have  further  learnt  that  from 
I  to  2  fluid  ounces  of  alcohol  is  about  the  amount  which  can  be 
safely  taken  in  one  day.  Now,  2  fluid  ounces  of  alcohol  are 
contained  in  one  bottle  of  good  claret  or  hock,  and  therefore  we  may 
conclude  that  half  a  bottle  daily  of  such  wines  is  the  limit  for  a 
sedentary  individual,  and  a  whole  bottle  is  enough  for  a  man  of 
more  active  life.  The  fortified  wines,  on  the  other  hand,  should  be 
reserved  for  special  occasions,  or  should  only  be  used  as  medicines 
under  medical  advice. 

Acids. — We  have  seen  that  acids  are  an  indispensable  ingredient 
of  all  wines,  and  that  they  are  chiefly  present  in  the  form  of 
bitartrate  of  potash,  but  that  some  wines  contain  a  certain  propor- 
tion of  volatile  acids,  such  as  acetic,  in  addition.  To  the  healthy 
man  the  amount  of  acid  present  in  any  reasonably  sound  wine  may 
be  regarded  as  harmless,  but  it  is  generally  believed  that  wines  with 
a  high  degree  of  acidity  may  be  injurious  to  some  constitutions,  and 
especially  to  the  gouty  and  the  rheumatic.  It  is  doubtful  whether 
this  proposition  can  be  maintained  in  such  an  absolute  form.  One 
must  remember  that  the  organic  acids  and  their  salts  contained  in 
wine  are  converted  in  the  body  into  alkaline  compounds,  and  are 
excreted  as  such.  Certainly  bitartrate  of  potash  increases  very 
appreciably  the  alkalinity  of  the  urine.     It  is  difficult  to  see,  there- 


ACTION  OF  ACIDS  393 

fore,  how  its  presence  in  wine  can  be  other  than  beneficial,  as  far  as 
gravel,  at  least,  is  concerned.  As  a  matter  of  fact,  Liebig  long  ago 
pointed  out  that  the  free  use  of  hock  (a  rather  acid  wine)  tended  to 
prevent  the  precipitation  of  uric  acid  in  the  urine.  The  same  is  true 
of  cider.  Those  who  drink  largely  of  it  are  not  troubled  with 
gravel ;  indeed,  they  are  stated  to  enjoy  a  special  immunity  from 
that  disease,  for  it  not  only  renders  the  urine  less  acid,  but  increases 
its  volume,  so  much  so,  indeed,  that  in  Normandy  the  young  and 
inexperienced  practitioner  is  constantly  diagnosing  an  imaginary 
diabetes. 

It  may  be  objected  that,  although  this  may  all  be  true  as  regards 
the  deposit  of  uric  acid  in  the  urinary  passages,  yet  the  acidity  of 
wines  may  render  them  harmful  in  the  tissues  before  the  oxidation 
of  their  organic  acids  into  alkaline  forms  has  had  time  to  take  place. 
Even  this,  however,  is  very  far  from  being  proved,  and  Luff  has 
showni  that,  as  a  matter  of  fact,  the  most  acid  wines  are  not  those 
which  are  most  generally  credited  with  being  producers  of  gout. 
The  supposed  connection,  indeed,  between  variations  in  the  alkalinity 
of  the  blood  and  the  occurrence  of  gout  has  probably  been  exagger- 
ated, and  demands  much  further  investigation. 

The  action  of  the  tannin  in  wine  must  be  sharply  distinguished 
from  that  of  its  other  organic  acids.  A  rough  or  astringent  and  an 
acid  wine  are  by  no  means  the  same  thing,  though  there  can  be  little 
doubt  that  the  former  is  often  mistaken  for  the  latter.  The  red 
wines,  as  a  class,  are  richer  in  tannin  than  the  white,  and  port, 
especially  when  young,  is  one  of  the  richest  of  all.  Burgundy,  on 
the  other  hand,  does  not  seem  to  contain  a  large  amount  of  this 
constituent.  Owing  to  this  property,  red  wines  may  be  useful  in 
diarrhoea  and  harmful  to  the  constipated,  but  it  is  a  mistake  to 
suppose  that  the  mere  presence  of  roughness  or  astringency  [i.e.,  of 
tannin)  in  a  wine  confers  upon  it  any  special  strengthening  qualities. 

Sugar. — There  can  be  little  doubt  that  the  craze  at  present  is  for 
dry,  i.e.,  sugar-free,  wines.  It  is  interesting  to  inquire  whether 
this  can  be  justified.  We  have  seen  that  the  total  amount  of  sugar 
which  can  be  consumed  daily  in  the  form  of  wine,  no  matter  how 
sweet,  is  so  small  that  it  can  be  neglected  from  a  merely  nutritive 
point  of  view.  The  further  question  therefore  arises,  Is  the  com- 
paratively small  quantity  of  sugar,  which  even  the  so-called  '  sweet ' 
wines  contain,  in  any  way  injurious  to  health  ?  Here,  again,  it  is 
the  gouty  who  are  believed  to  be  subject  to  special  risks.  There  is 
no  more  reason,  however,  to  believe  that  the  sugar  of  wines,  per  s«, 

'  'Gout:  its  Pathology  and  Treatment,'  Cassell  and  Co.,  i8g8. 


394  FOOD  AND  DIETETICS 

is  any  n\ore  harmful  to  such  persons  thau  their  acids  are.  It  is 
interesting  to  note  in  this  connection  that  it  is  the  fortified  wines 
which,  as  a  class,  are  the  sweet  wines,  and  the  natural  wines  which 
(with  a  few  exceptions)  are  dry,  and  the  suspicion  naturally  arises 
that  it  is  the  greater  amount  of  alcohol  in  the  sweet  wines  which 
renders  them  dangerous  to  the  gouty  (even  granting  that  such 
danger  has  been  proved  to  exist),  rather  than  the  sugar  which  they 
also  contain. 

It  is  probable,  indeed,  that  it  is  the  combined  presence  of  both 
sugar  and  acid  in  a  wine  which  renders  it  harmful  to  the  class  of 
whom  we  are  speaking  rather  than  either  of  these  ingredients  alone. 
There  is  certainly  some  reason  to  believe  that  such  a  wine  is  more 
apt  to  excite  an  '  acid '  dyspepsia  in  gouty  subjects  than  dry  wines 
are.  This  may  perhaps  be  due  to  the  rapid  absorption  of  sugar 
from  the  stomach  in  the  presence  of  alcohol,  and  its  replacement  by 
a  large  quantity  of  highly  acid  gastric  juice.  It  may  perhaps  be  the 
case,  too,  that  fermentation  is  apt  to  be  restarted  in  a  fortified  wine 
once  its  alcohol  is  diluted  in  the  stomach,  and  that  this  may  give 
rise  to  the  production  of  acid  substances.  Be  the  explanation  what 
it  may,  the  gouty  man  does  well  to  avoid  the  fortified  wines  unless 
very  dry,  for  such  a  dyspepsia  is  prone  to  be  the  signal  for  an  attack 
of  gout.^ 

The  action  of  the  extractives  of  wine  on  the  body  is  obscure.  It 
has  been  supposed  by  some  that  their  influence  is  akin  to  that  of  the 
extractives  of  meat,  and  they  are  believed  to  help  in  the  making  of 
blood.  It  may  be  worth  while  remembering  that  extractives  are 
most  abundant  in  old  wines  and  those  of  good  vintage. 

*  The  Lancet  (1899,  i.  525)  gives  the  following  list  of  practically  sugar-free 
liquors  which  may  be  recommended  to  diabetics  and  the  gouty  : 

Per  Cent.  0/ Sugar. 
Champagne  '  Sans  Sucre'  (Hertz  and  CoUingwood)  . .         0*2 

Californian  Burgundy  (Haig,  Smith  and  Co.,  Manchester)..         015 
,,         Claret  ,,  ,,  ,,  ..        014 

Australian  Burgundy  (Burgoyne)  ,,  ,,  .,        0*28 

South  Australian  wines  (Orion  Brand,   E.  Burney  Young, 
35,  Walbrook  Street,  EC.)  : 

Cabernet   ..  ..  ..  ..         ..         ..         ..         014 

Burgundy..         ..         ..         ..         ..         ..         ..        oiO 

Reisling     ..  ..  ..  ..  ..  ..         .,         020 

Dry  Imperial  Champagne  (Moet  and  Chandon)         ..         ..         o"65 

Cider  (Gaymer  and  Son)  ..         07  to  2- 12 

Harvey's  Pale  Ale  . .         . .         . .         . .         None. 

Back  and  Co.'s  Anti-diabetic  Non-acid  Whisky         ..  ..  ,, 

Dewar  and  Sons      . .         . .         . .         . .         . .         . .         . .  , , 

Vibrona  Champagne         o'i3 

^  ,,        Sherry 020 

Vitiili's  Italian  wines         •.        ..        o'ittoo-17 


SUMMARY  395 

The  volatile  constituents  of  witie  include  the  ethers  and  essential 
oils,  the  latter,  along  with  certain  highly-oxidized  aldehydes,  being 
probably  chiefly  responsible  for  the  quality  kno^vn  as  *  bouquet.' 
The  action  of  these  upon  the  body  in  health  is  probably  slight, 
though  they  may  exercise  a  modifying  influence  upon  the  intoxicating 
tendency  of  the  alcohol  along  with  which  they  occur.  In  disease, 
on  the  other  hand,  the  ethers,  and  especially  their  volatile  members, 
seem  to  have  often  a  most  valuable  stimulating  influence  on  the 
exhausted  brain  and  heart. 

In  attempting  to  summarize  the  points  which  have  been  raised  in 
this  discussion  as  to  the  use  of  wines  in  health,  I  cannot  do  better 
than  quote  the  conclusions  of  Anstie  •} 

1.  Wines  for  daily  use  by  healthy  adults  should  not  on  the 
average  contain  more  than  lo  per  cent,  absolute  alcohol  (by  weight) ; 
8  or  9  per  cent,  is  better. 

2.  If  wine  be  used  as  the  daily  drink,  it  is  best,  as  far  as  may  be, 
to  use  only  one  kind  at  a  time  and  no  other  form  of  alcoholic  liquid. 

3.  Sound  natural  wines  are  to  be  obtained  at  the  best  economic 
advantage  from  the  Bordeaux  district ;  the  red  wines  are  to  be 
preferred. 

4.  Rhine  wines  (white)  are  equally  excellent,  but  more  expensive. 

5.  Hungarian  wines  are  also  in  many  instances  excellent,  but 
they  are  unequal  in  quality  owing  to  defects  of  manufacture. 

6.  Greek  wines  labour  under  the  same  defects. 

7  The  fortified  wines,  as  a  class,  develop  no  proper  vinous 
qualities  till  they  have  been  for  some  years  in  bottle.  Sherry, 
however,  is  greatly  superior  to  the  other  wines  of  this  class  in  the 
rapidity  with  which  it  develops  the  volatile  ethers. 

8.  Fortified  wines  in  small  quantities,  especially  sherry,  for  the 
reason  just  named,  are  the  appropriate  stimuli  of  certain  kinds  of 
infantile  and  youthful  debility,  and  of  the  enfeebled  nervous  system 
of  old  persons. 

9.  Half  a  bottle  of  a  natural  wine  a  day  for  a  sedentary  and  a 
bottle  a  day  for  a  vigorous  and  actively-employed  adult  affords  a 
reasonable  and  prudent  allowance  of  alcohol,  and  this  quantity  of 
wine,  either  alone  or  with  water,  will  be  enough  to  satisfy  the  needs 
of  moderate  persons  for  a  beverage  at  lunch  and  dinner,  the  only 
two  meals  at  which  alcohol  should,  as  a  rule,  be  taken. 

The  use  of  wines  in  disease  will  be  considered  in  subsequent 
chapters. 

^  'Ou  the  Uses  of  Wines  in  Health  and  Diseaise'(MacmiUaB  and  COb,  1877). p.  39. 


[396] 


CHAPTER  XXII 
THE  COOKING  OF  FOODS* 

The  object  of  cooking  food  is  twofold  : 

1.  /Esthetic — to  improve  its  appearance  and  to  develop  in  it  new 
flavours. 

2.  Hygienic — to  sterilize  it  to  some  extent  and  to  enable  it  to  keep 
longer.2 

It  is  an  error  to  suppose  that  cooking  increases  the  digestibility  of 
food.  That  is  only  true  of  vegetable  foods.  The  digestibility  of 
animal  foods  is  dimiViished  rather  than  increased  by  cooking.  This 
is  true  at  least  of  the  chemical  processes  of  digestion,  though  the 
increased  attractiveness  of  well-cooked  food  may  render  it  indirectly 
more  capable  of  digestion  by  calling  forth  a  more  profuse  flow  of 
psychical  gastric  juice  (see  p.  417). 

The  application  of  heat  in  some  form  or  another  being  the 
essential  part  of  all  ordinary  processes  of  cooking,  it  is  important 
to  have  clear  ideas  as  to  the  effect  of  heat  npon  the  different  chemical 
constituents  of  food. 

The  effect  of  heat  on  the  proteins  of  the  food  is  to  coagulate  them. 
It  would  be  a  complete  mistake,  however,  to  suppose  that  a  boiling 
temperature  is  essential  for  bringing  about  this  change,  for  all  pro- 
teins, both  animal  and  vegetable,  are  coagulated  if  their  temperature 
be  raised  to  170°  F.  We  shall  subsequently  see  that  ignorance  of 
this  fact  is  a  fertile  source  of  errors  in  cooking.  If  the  temperature 
be  raised  much  above  this  point,  the  protein  tends  to  shrink  and 
harden,  and  the  digestibility  of  the  food  in  which  it  is  contained  is 
proportionately  lessened. 

Of  the  carbohydrates  of  the  food,  starch  is  most  affected  by  heat. 

^  The  reader  may  also  consult  on  this  subject  'The  Chemistry  of  Cookery,' 
by  W.  Matthieu  Williams  (London,  Chatto  and  Windus^  1892);  Thudichum's 
'  Spirit  of  Cookery'  (London,  Bailliere,  Tindall  and  Cox,  1895);  and  Sir  Henry 
Thompson's  '  Food  and  Feeding,'  ninth  edition  (London,  Frederick  Warne 
and  Co.),  chapters  v.  and  vi. 

2  Ko  animal  parasite  found  in  meat  is  capable  of  vijithstanding  a  temperature  of 
70*  C.  All  ordinary  forms  of  cooking  will  therefore  render  meat  free  from  this 
source  of  infection.  On  the  other  hand,  many  pathogenic  bacteria,  such  as  those 
of  splenic  fever,  malignant  oedema,  septicaemia,  and  chicken  cholera,  if  present  in 
the  interior  of  meat,  might  quite  easily  escape  being  killed  by  the  temperatures 
nsaally  reached  in  ordinary  methods  of  cooking. 


THE  COOKING  OF  FOODS  397 

Dry  heat  converts  starch  into  a  soluble  form,  and  ultimately  into 
dextrin.  This  change  occurs  to  a  limited  extent  in  the  crust  of 
bread,  and  also  in  the  making  of  toast.  Moist  heat  causes  the 
starch  grains  to  swell,  and  ultimately  to  rupture  their  cellulose 
envelopes,  and  the  starch  is  then  said  to  be  gelatinized.  That  this 
change  also  takes  place  considerably  below  the  boiling-point  of 
water  is  shown  by  the  following  table  of  the  gelatinization-points  of 
different  kinds  of  starch  :^ 

Oat 185°  F. 

Barley            176°  F. 

Rye 176°  F. 

Wheat            176°  F. 

Rice 176°  F. 

Maize             167°  F. 

Potato            149°  F- 

Here  again  one  sees  that  in  the  case  of  some  starchy  foods,  at  any 
rate,  the  change  which  it  is  the  object  of  cooking  to  effect  can  be 
brought  about  at  a  comparatively  low  temperature. 

The  effects  of  heat  upon  sugar  have  already  been  described,  and 
it  need  only  be  mentioned  here  that  the  partial  conversion  of 
sugar  into  caramel  is  one  of  the  means  by  which  flavour  is  developed 
in  food  by  cooking. 

The  fats  of  food  are  not  so  much  affected  by  heat  as  the  proteins 
and  carbohydrates.  At  high  temperatures,  however,  as  when  one 
of  the  dry  methods  of  cooking  is  employed,  some  at  least  of  the 
fat  may  perhaps  undergo  a  partial  decomposition,  ^vith  the  libera- 
tion of  free  fatty  acid.^  This  may  explain  why  it  is  that  hot  fat 
is  so  much  more  apt  to  prove  irritating  to  the  stomach  than  cold 
fat,  for  it  is  not  improbable  that  the  fatty  acid  may  reunite  with 
glycerine  to  form  neutral  fat  on  cooling.  Fat  which  has  been 
heated  and  allowed  to  cool  again  is  often  found  to  have  become  more 
granular  than  it  was  before.  This  change  is  probably  due  to  the 
driving  off  of  water,  and  it  tends  to  render  the  fat  more  brittle,  and 
consequently  more  digestible  than  it  was  before.  The  change  is  well 
exhibited  in  the  case  of  dripping,  and  also  in  fried  bacon. 

With  these  preliminary  considerations  we  may  proceed  to  the 
study  of  the  effects  of  cooking  upon  animal  and  vegetable  foods 
respectively. 

I.  Cooking  of  Meat. 

The  ideal  to  be  aimed  at  in  cooking  meat  is  to  decompose  its  red 
colouring  matter  (haemoglobin),  so  as  to  remove  its  raw  appearance. 

^  From  Sykes'  *  Principles  and  Practice  of  Brewing,'  p.  70. 
«  See  also  Matthieu  "Williams'  '  Chemistry  of  Cookery,'  p.  158. 


398  FOOD  AND  DIETETICS 

and  to  do  this  without  overcoagulating  the  solid  proteins  of  the 
meat  or  removing  from  it  its  flavouring  ingredients  (extractives). 

We  may  glance  very  briefly  at  the  means  by  which  this  ideal  is 
to  be  attained  in  the  ordinary  methods  of  cool^ing. 

I.  Boiling. — It  is  unfortunate  that  the  term  '  boiling  '  should  be 
applied  at  all  to  any  metliod  of  cooking  meat,  for  it  implies  that  the 
subjection  of  the  meat  to  the  temperature  of  boiling  water  (212°  F.) 
is  an  essential  of  the  process.  But  this,  for  the  reasons  indicated 
above,  is  a  mistake.  The  red  colouring  matter  of  the  meat  is 
decomposed  and  rendered  brown  at  a  temperature  considerably 
below  that  of  boilin,^;  water,  and  by  going  up  to  the  boiling-point 
one  runs  the  risk  of  hardening  the  meat  by  overcoagulation  of  its 
proteins. 

That  the  boiling-point  is  not  essential  for  the  complete  coagulation 
of  the  proteins  can  be  most  easily  proved  in  the  case  of  an  egg.  If 
two  eggs  are  taken,  and  one  kept  in  water  at  a  temperature  of  175°  F. 
for  ten  or  fifteen  minutes,  and  the  other  for  an  equal  length  of  time 
in  boiling  water,  it  will  be  found  at  the  end  of  the  experiment  that 
the  contents  of  both  are  solid  throughout,  but  that  in  the  case  of  the 
former  they  consist  of  a  tender  jelly,  whereas  in  the  boiled  egg  they 
are  dense  and  almost  leathery.  Several  so-called  egg-boilers, 
indeed,  have  now  been  introduced  which  go  upon  the  correct 
principle  of  cooking  the  egg  at  a  temperature  considerably  below  the 
boiling-point  of  water. 

Now,  what  is  true  of  an  egg  holds  good  also  for  meat,  and 
accordingly  the  first  principle  to  be  observed  in  the  '  boiling '  of 
meat  is  to  see  that  the  temperature  of  the  water  does  not  rise 
much  above  that  which  is  required  for  the  coagulation  of  proteins. 
It  is  only  by  giving  heed  to  this  that  one  can  achieve  the  first  result 
desired — the  abolition  of  the  raw  colour  of  the  meat  with  avoidance 
of  overhardening. 

The  second  object  to  be  aimed  at,  that  of  retaining  all  the  flavour- 
ing constituents  of  the  meat,  also  demands  some  care.  The  flavour 
of  meat  is  due  to  its  extractives  and  salts,  and  both  of  these  are 
readily  dissolved  by  water.  If  the  water  in  wjiich  the  meat  has 
been  cooked  is  to  be  consumed  in  the  form  of  soup,  the  partial 
removal  of  some  of  these  flavouring  ingredients  is  not  of  much 
importance ;  but  if  the  meat  alone  is  to  be  eaten,  precautions  must 
be  taken  to  prevent  their  being  dissolved  out. 

One  way  of  doing  this  is  to  use  as  small  a  quantity  of  water  as 
possible.;  for  the  larger  the  proportion  of  water  to  meat,  the  greater 


COOKING  OF  MEAT  399 

will  be  the  amount  of  soluble  substances  removed.  The  quantity 
of  water,  therefore,  should  be  just  sufficient  to  cover  the  meat,  and 
no  more. 

The  other  way  of  obviating  removal  of  soluble  substances  is  to 
seal  up  the  piece  of  meat.  This  is  best  achieved  by  plunging  it  into 
boiling  water,  and  leaving  it  there  for  a  few  minutes.  This  causes 
a  rapid  and  complete  coagulation  of  the  protein  in  the  fibres  of  the 
meat,  which  forms  an  almost  impermeable  layer  on  the  surface,  and 
shuts  in  the  soluble  constituents.^  When  this  has  been  done,  the 
temperature  of  the  water  should  be  lowered,  and  the  process  of 
cooking  continued  slowly. 

2.  In  the  process  of  roasting  the  heat  is  conveyed  to  the  meat  by 
direct  radiation,  instead  of  through  the  medium  of  water.  Here, 
again,  high  temperatures  should  be  avoided,  except  at  the  outset, 
when  it  is  necessary  to  effect  a  sealing  of  the  surface,  for  the  same 
reason  as  in  boiling.  If  the  piece  of  meat  be  thin,  the  high  tempera- 
ture to  which  it  is  first  exposed  not  only  seals  the  surface,  but  also 
coagulates  the  protein  throughout  the  whole  thickness,  so  that  the 
meat  is  practically  cooked  at  once.  This  happens,  for  instance, 
when  a  chop  is  cooked  on  the  grill,  and  the  completeness  of  the 
sealing  is  shown  by  the  fact  that  the  water  vapour  produced  from 
the  fluids  in  the  meat  is  unable  to  escape,  and  by  its  expansion 
causes  the  chop  to  assume  that  puffy  form  which  is  a  sign  of  skilful 
cookery.  In  the  case  of  a  large  joint  the  heat  does  not  penetrate 
with  sufficient  rapidity  to  admit  of  instantaneous  cooking,  and  in 
that  case  a  long  exposure  to  a  lower  temperature  is  required  after 
the  surface  has  once  been  sealed.  Desiccation  of  the  meat  during 
this  period  is  prevented  by  continuous  basting,  which  forms  a  sort 
of  impenetrable  varnish  of  fat  over  the  surface.  Roasting,  if  properly 
performed,  not  only  prevents  the  escape  of  the  natural  flavourers  of 
the  meat,  but  develops  in  it  substances  which  are  themselves  of  a 
sapid  nature.  This  is  due  to  a  change  which  it  brings  about  in 
the  extractives  on  the  surface,  analogous  to  the  alteration  which 
sugar  undergoes  in  its  conversion  into  caramel.  This  results  in  the 
production  of  the  dark-brown,  sticky  substance  on  the  surface  of  a 
roast  joint  which  is  familiar  to  everyone,  and  which  is  sometimes 
termed  osmazone.     It  is  one  of  the  most  sapid  substances  known. 

»  Recent  experiments  in  America,  however,  have  shown  that  if  meat  be  cooked 
ill  water  at  80°  to  85°  C,  placing  the  meat  in  hot  or  cold  water  at  the  start  has 
but  little  effect  on  the  amount  of  material  found  in  the  broth  (U.S.  Dept.  of 
Agriculture,  Off.  of  Experiment  Stations,  Bull.  No.  141,  1904)- 


400  FOOD  AND  DIETETICS 

Experiments  which  have  been  made  in  America^  show  that  roasts 
are  cooked  as  quickly  at  a  temperature  of  175°  C.  as  at  195°  C. 
This  is  of  practical  importance  from  the  point  of  view  of  economy  in 
fuel.  When  cooked  at  100°  C,  a  very  much  longer  time  is  required 
to  raise  the  inner  temperature  from  medium  (62°  C.)  to  well-done 
(72"  C.)  than  to  cause  the  same  rise  at  195°  C.  or  175**  C.  There 
is,  therefore,  much  less  danger  of  over-cooking  the  meat  at  this 
temperature  (loo**  C). 

3.  Baking  acts  in  precisely  the  same  way  as  roasting,  the  heat  in 
that  case  being  applied  all  round  the  meat  at  once,  instead  of  only 
to  one  side  at  a  time.  The  production  of  osmazone  by  this  process 
is,  however,  rather  limited. 

4.  Stewing  is  in  many  respects  the  ideal  method  of  cooking  meat. 
If  properly  performed,  it  coagulates  without  overhardening  the 
proteins,  while,  owing  to  the  fact  that  the  juice  is  eaten  along  with 
the  meat,  none  of  the  flavouring  ingredients  are  lost.  At  the  same 
time,  the  prolonged  action  of  heat  and  moisture  converts  most  of  the 
connective  tissue  into  gelatin,  so  that  the  fibres  readily  fall  apart 
and  the  meat  becomes  very  tender.  Here,  again,  the  secret  of 
success  consists  in  avoiding  too  high  temperatures.  It  is  not 
sufficient  to  place  the  pan  by  the  side  of  the  fire,  and  allow  it  to 
*  simmer '  instead  of  '  boil.'  The  use  of  a  thermometer  will  show 
that  the  temperature  of  '  simmering '  and  *  boiling '  water  is  really 
the  same,  i.^.,  212°  F.,  the  only  difference  being  that  in  the  former 
case  the  heat  is  reaching  the  water  more  rapidly  and  more  of  it  is 
wasted.  In  proper  stewing  the  temperature  should  not  be  allowed 
to  rise  above  180°  F. 

2.  Cooking  of  Fish. 

The  flavouring  ingredients  of  fish  are  even  more  easily  dissolved 
out  by  water  than  those  of  meat ;  and  as  fish  has  less  flavour  to 
start  with,  any  loss  is  the  more  carefully  to  be  avoided.  For  this 
reason  boiling,  unless  very  carefully  performed  on  the  lines  above 
laid  down,  is  not  a  suitable  method  of  cooking  fish.  The  experi- 
ments of  Sir  Henry  Thompson  ^  show  that  even  when  carefully 
performed  it  is  apt  to  result  in  a  loss  of  at  least  5  per  cent,  of  solid 
matter.  For  this  reason  cooking  by  means  of  water-vapour  (steam- 
ing) is  preferable,  just  as  it  is  in  the  case  of  some  vegetables. 

»  '  A  Precise  Method  of  Roasting  Beef.*    The  University  Studies  (Urbana,  HI., 
U.S.A.),  vol.  ii.,  No.  4,  May,  1907. 
*  •  Food  and  Feeding,'  p.  196. 


COOKING  OF  FISH  40> 

Frying  is  a  method  of  cooking  specially  applicable  to  some  forms 
of  fish,  and  demands  a  special  word  of  description,  especially  as  the 
process  is  so  often  misunderstood. 

The  essence  of  frying  consists  in  the  sudden  exposure  of  the  object 
to  be  cooked  to  a  very  high  temperature.  This  has  the  effect  of 
producing  an  instantaneous  coagulation  of  the  proteins  on  the 
surface,  along  with  a  slight  degree  of  charring.  Any  escape  of 
soluble  substances  is  thus  prevented,  while  the  surrounding  tempera- 
ture is  so  high  that  the  fish  or  other  substance  is  practically  cooked 
throughout  its  whole  thickness  almost  instantaneously. 

In  order  to  attain  this  very  high  temperature,  some  form  of  fat 
must  be  used  as  a  medium.  Olive-oil  or  good  cottonseed-oil  are 
best.  The  oil  should  be  heated  in  a  deep  pan  almost  to  its  boiling- 
point  (the  actual  temperature  is  about  350°  to  390°  F.) ;  and  when 
this  temperature  has  been  reached  the  object  to  be  fried  should  be 
suddenly  plunged  into  the  pan,  and  left  for  two  or  three  minutes. 
The  sputtering  which  ensues  is  due  to  the  sudden  conversion  of  the 
moisture  on  the  surface  of  the  object  into  steam.  When  this  has 
ceased  the  cooking  will  be  complete,  and  the  object  should  be  lifted 
out  and  the  excess  of  oil  allowed  to  drain  off. 

It  will  be  observed  that  this  process  differs  entirely  from  the 
so-called  '  frying  '  usually  practised  in  this  country,  in  which  the  fat 
employed  is  regarded  merely  as  a  means  of  preventing  the  object 
from  adhering  to  the  surface  of  the  shallow  pan,  in  which  a  sort  of 
roasting  is  really  accomplished. 

3.  Cooking  of  Vegetable  Foods. 

In  the  cooking  of  vegetable  foods  the  objects  to  be  achieved  are 
different  from  those  which  one  seeks  to  accomplish  in  the  case  of 
animal  foods.  Cellulose  and  raw  starch  are  almost  incapable  of 
digestion  by  man,  and  hence  the  softening  and  rupture  of  the 
cellulose  framework  of  a  vegetable  food  and  the  gelatinization  of 
its  starch  grains  are  the  chief  ends  which  it  is  the  purpose  of 
cooking  to  bring  about. 

Cellulose  can  be  softened,  and,  indeed,  partly  converted  into  sugar, 

by  the  action  of  acids,  aided  by  heat.     This  is  Nature's  method  of 

dealing  with  it.     In  its  unripe  state  a  pear  or  other  fruit  is  hard  and 

'  woody '  from  the  presence  of  a  cellulose  framework.     In  process  of 

ripening  the  acids  in  the  fruit,  aided  by  the  heat  of  the  sun,  effect  a 

softening  of  this  framework,  with  partial  or  complete  solution  of  the 

cellulose  fibres,  the  product  being  the  sweet  and  soft  ripe  fruit. 

26 


4©3 


FOOD  AND  DIETETICS 


This  method  is  sometimes  unconsciously  imitated  by  man.  The 
process  of  preparing  ensilage  is  an  example  of  it.  Here,  under  the 
influence  of  fermentative  bacteria,  acids  are  produced  in  grass 
which,  by  the  aid  of  moisture  and  heat,  act  upon  the  cellulose,  and 
effect  a  partial  conversion  of  it  into  sugar.  In  Germany  a  very 
similar  process  is  employed  in  the  conversion  of  cabbages  into 
sauer-krautA 

The  preparation  known  as  savans  is  an  example  of  the  operation 
of  a  similar  agency  on  the  cellulose  of  oatmeal.  Ordinary  porridge, 
also,  when  allowed  to  stand  for  some  time,  becomes  a  soil  for  the 
growth  of  acid-forming  bacteria,  and  the  products  of  the  growth  of 
these  bring  about  some  degree  of  softening  of  the  cellulose  in  the 
particles  of  oatmeal.  For  this  reason  porridge  is  often  found  to  be 
more  digestible  when  stale  than  when  perfectly  fresh. 


Fig.  29. — Cells  of  a  Raw  Potato,  with  onrdptdred  Starch  Grains  and 
Cellulose  Framework. 

Another  way  of  overcoming  the  cellulose  obstacle,  which  may  in  a 
sense  be  regarded  as  a  process  of  cooking,  is  by  milling  or  grinding. 
This  breaks  up  the  cellulose  framework,  and  allows  the  digestive 
juices  to  penetrate  into  the  nutritive  ingredients  which  it  encloses. 

More  commonly,  however,  one  finds  the  same  object  accomplished 
by  the  combined  action  of  heat  and  moisture.     When  exposed  to 

*  It  is  denied  by  some  that  cellulose  is  really  acted  upon  by  acids,  and  they 
attribute  the  results  obtained  io  the  above  instances  to  the  action  of  other 
agencies. 


COOKING  OF  VEGETABLES  \o^ 

moist  heat  starch  grains,  as  we  have  seen,  swell  up,  their  envelopes 
rupture,  and  they  run  together  to  form  a  paste  or  starch  jelly.     As 


Fio.  30.— Cells  of  a  Partially  Cooked  Potato,  the  Starch  Graihs 

Ruptured. 


Fio.  31. — Cells  or  a  thoroughly  Boiled  Potato;  Cellulose  Framework 

BROKEN    DOWN. 

tills  jelly  expands  it  presses  upon  and  ultimately  ruptures  the  frame- 
work of  cellulose  in  which  the  grains  are  enclosed,  and  in  this  way 
the  two  chief  objects  aimed  at  are  achieved.     The  degree  to  which 


404  FOOD  AND  DIETETICS 

this  occurs  in  diflferent  cases  is  very  well  shown  in  the  accompanying 
diagrams  (Figs.  29,  30  and  31),  which  illustrate  the  action  of  moisture 
and  heat  upon  the  structure  of  a  piece  of  potato. 

It  will  be  evident  from  these  considerations  that  cooking  is  of 
immense  importance  in  facilitating  the  digestion  of  vegetable  foods, 
and  the  larger  the  proportion  of  cellulose  present,  the  more  essential 
does  thorough  cooking  become. 

On  the  proteins  of  vegetables  heat  has  an  sfFect  precisely  similar  to 
that  which  it  exerts  on  the  same  constituent  of  animal  food ;  that 
is  to  say,  they  become  coagulated.  Now,  the  coagulation  of  proteins 
is  accompanied  by  shrinkage  rather  than  by  swelling,  and  for  this 
reason,  if  the  cellulose  framework  encloses  protein  only,  it  does  not 
become  ruptured  ;  and  one  can  therefore  readily  understand  that  if 
a  vegetable  food  contained  protein  only  its  digestibility  would  be 
affected  by  cooking  in  a  precisely  similar  way  to  that  of  animal 
food  ;  in  other  words,  it  would  be  rendered  less  rather  than  more 
digestible  by  the  process.  As  a  matter  of  fact,  however,  there  are 
few  vegetable  foods  which  do  not  contain  much  starch  as  well  as 
protein,  and  hence  it  is  that  the  general  rule  holds  good  that  cooking 
increases  their  digestibility. 

Losses  in  Cooking. 

No  matter  how  carefully  cooking  is  performed,  a  certain  amount  of 

loss  of  the  soluble  constituents  of  the  food  during  the  process  is 

almost  inevitable.     In   the   case   of  meat,   it   has  been   found   by 

Johnston  that — 

In  Boiling.  In  Baking.  In  Roasting. 

4  lb.  of  beef  lose  in  weight     . .         i  lb.  i  lb.  3  oz.  i  lb.  5  oz. 

,,      mutton  lose  in  weight          14  oz.  1  lb.  4  oz.  i  lb.  6  oz. 

By  far  the  larger  part  of  this  loss,  however,  is  due  to  water.  This 
is  fhown  by  the  following  analyses  given  by  Konig  : 

COMPARATIVE   COMPOSITION   OF  MEATS   BEFORE  AND   AFTER 

COOKING. 


Water. 

Nitrogenous 
Matter. 

Fat. 

Extractive 
Matter. 

Salts. 

Beef: 

Per  cent. 

Per  cent. 

Per  cent. 

Per  cent. 

Per  cen 

Before  cooking  (raw)     . .       7088 
Same  after  boiling         ..       5682 
Same  after  broiling    (as 
beefsteak)         ..         ..       5539 
Veal  cutlets : 

22  51 
3413 

3423 

452 
750 

8-21 

•86 
•40 

72 

123 

I-I5 

145 

Before  roasting  (raw)    . 
Same  after  roasting 

•  71-55 

•  5759 

20  24 
29  00 

638 
11-95 

•68 
•03 

115 
I  43 

The  actual  loss  of   soluble  matter  is  more  clearly  brought  out 
when  these  figures  are  recalculated  on  the  basis  of  dry  substance :  ^ 
*  Bulletin  21,  United  States  Department  of  Agriculture,  p.  87. 


LOSSES  IN  COOKING 


405 


COMPARATIVE   COMPOSITION   OF   WATER-FREE   SUBSTANCE 
OF   MEATS   BEFORE  AND   AFTER   COOKING. 

Nitrogenous 

Matter. 

Per  cent. 

77-31 


Beef: 

Before  cooking 
After  boiling 
After  roasting 
Veal  cutlets : 
Before  cooking 
After  roasting 


Nitrogen. 

Per  cent. 
1237 
12-65 
1227 


"•39 
10-93 


79  06 
7673 

71-17 
68-36 


Fat. 

Per  cent. 

15-47 


Extractive 
Matter. 
Per  cent. 


1738 
1 8*4 1 

22-45 
28-18 


Salts. 

Per  cent. 
4-24 


•90 
1-59 


232 
•09 


2-66 
327 

4'o6 
337 


It  will  be  observed  that  the  loss  is  entirely  confined  to  the  extractive 
matter  and  salts. 

As  far  as  their  soluble  constituents  are  concerned,  vegetable  foods 
behave  similarly,  the  loss  of  salts  especially  being  often  very  con- 
siderable. This  point,  however,  has  been  fully  dealt  with  when  the 
composition  of  vegetable  foods  was  described.^ 

As  regards  water,  the  behaviour  of  the  two  classes  of  foods  on 
cooking  is  entirely  different,  for  vegetable  foods  tend  to  become 
richer  in  water  when  cooked,  instead  of  losing  it.  The  contrast 
between  the  two  in  this  respect  is  very  well  shown  in  the  following 
figures  given  by  Forster  : 


COMPARISON  OF   THE   EFFECTS  OF  COOKING  ON  THE  PROPOR- 
TION OF  WATER  IN  ANIMAL  AND  VEGETABLE  FOODS. 


Paw. 

Cooked. 

Beef.. 

. .     75  per  cent. 

Boiled.. 

55  to  59  per  cent. 

Roast  .. 

56  to  63 

Veal . . 

..     78        .. 

Roast  .. 

60  to  64       , , 

Flour 

..     12  to  14  per  cent. 

Bread  .. 

36  to  40       ,, 

chewed 

70  per  cent. 

Peas 

. .     14  per  cent. 

Peas  brose 

68  to  78  per  cent. 

Pea  soup 

90  per  cent. 

Potatoes 

••     75 

Potato  puree  . . 

78       .. 

soup    .. 

91 

Cabbage 

..     87        .. 

Cabbage 

85  to  90  per  cent. 

One  may,  therefore,  lay  It  down  as  a  general  proposition  that 
animal  foods  become  less  watery  as  the  result  of  cooking,  while 
vegetable  foods,  on  the  contrary,  become  more  watery. 

This  is  another  explanation  of  the  different  effect  which  cooking 
exerts  on  the  digestibility  of  the  two  classes  of  foods.  The  con- 
centration which  meat  undergoes  when  cooked  is  unfavourable  to 
digestion,  while  the  dilution  of  the  vegetable  foods  after  cooking 
makes  less  demand  on  the  digestive  juices.  This,  too,  is  one  reason 
why  meat  which  has  been  cooked  more  than  once  is  rather  difficult 
of  digestion.    Not  only  are  its  proteins  apt  to  be  over-coagulated,  but 

'  See  also  United  States  Department  of  Agriculture,  Bulletin  43,  'Losses  in 
Boiling  Vegetables,'  etc. 


4o6  FOOD  AND  DIETETICS 

the  relative  proportion  of  fat  is  increased  at  the  same  time,  and  both 
of  these  facts  militate  against  rapid  and  easy  digestion. 

On  the  other  hand,  the  increase  of  bulk  which  vegetable  foods 
undergo  as  the  consequence  of  taking  up  water  in  the  course  of 
cooking  is  apt,  for  reasons  already  explained,  to  throw  a  strain  on 
the  mechanical,  as  opposed  to  the  purely  chemical,  functions  of  the 
digestive  organs.  The  bearings  of  this  fact  upon  the  practice  of 
vegetarianism  have  been  discussed  at  length  in  an  earlier  chapter. 

COMPOSITION    OF    SOME    COOKED    VEGETABLE    FOODS 
(EXCLUDING  PROTEIN).! 

Names.  Water.        Fat.       ^"/"^^    Starch. 

Semolina     ..         ..         ..         ,.        ,.  90*17  0*08  0*04  7*24 

Sago..         .,         ..         ..         ,,         ,,  Sg'oo  0*04  o-oi  935 

Oswego 87-32  0-02  o-oi  9-68 

Vermicelli 87-14  o-oi  0-07  10-82 

Arrowroot" 93  "41  Trace  o-oi  4-83 

Benger's  Food,  cooked  with  milk*       ..  8830  2-57  0-23  8-17 

Quaker  Oats           ..         ..         ..         ..  92*48  0-32  009  6-25 

Provost  Oats          ..          ..          ..          ..  88-44  o"36  016  g-oo 

Farola  (fine  grain)            ,,         .,         ,.  90-24  0-02  0-06  7-22 

Farola  (large  grain)          8608  o-oi  0-15  11-06 

Florador  (large  grain)      ..         ..         ,.  89-45  o'oi  o'o8  8-67 

Granola       ..         ..         ..         ..         ..  87-40  0-03  o-io  9*42 

Farola  (medium  grain)     ..         ..         ..  89-15  o-oi  o-o6  889 

Pearl  barley            8501  0*07  o-io  12-98 

Mother's  oats         ..         ..         ..         ,,  89-72  0-45  0-15  8-70 

Hominy       ..         , 86-63  o"09  o'i6  9*87 

APPROXIMATE  COMPOSITION  OF  EDIBLE  PORTION  OF  SOME 
COOKED  VEGETABLE  FOODS. 

H^attr.        Ash.     j^^^gf^".     Fat.        Fibri.      Starch. 

Banana  flour            9i'9i  o'3i  2-30  006  0-18  503 

Soyabeans 66-14  i'23  16-00  6-05  3-08  7-65 

Green  flagorets         62-77  o'92  12-56  088  2-88  21-23 

Plasmon  arrowroot  . .         ..         ..  92-90  022  0-81  o-oi  o-oi  6-12 

Provost  barley          90-53  0-13  288  0-04  0-09  6-61 

Provost  barley  and  oats     ..         ..  85-17  0*27  268  0-42  0-30  n-02 

Asparagus 92'i8  1-31  1-76  0-37  0-52  4-44 

Frame  food 93'85  0*27  072  0-82  0-08  4-63 

Boyd's  banana  food           ..         ..  88-33  o'S^  3*9°  0-38  0-14  6-26 

Rice    ..         ..         71-88  o-io  1-92  0-05  0-09  27-07 

Celeriac         94'4i  o'42  0-95  0-15  0-90  2-82 

Butter  beans              63y4  i'2i  8-96  0S2  268  21-67 

Chicory         94 '59  0-32  1-42  o-io  0-51  299 

Chestnuts 71 '08  0-64  3-59  0-81  1-54  23-46 

Borecole(Scotch  kale,  curly  greens)  89-05  0*83  3-71  0-73  1-08  3-94 

Endive            9543  0-55  0-52  0-23  071  2-73 

Revalenta  arabica        94'3o  o"i5  ^"^9  0-03  0-07  4-38 

^  From  analyses  by  Miss  Katherine  J.  Williams.       *  West  Indian,  is.  ^d.  per  lb. 

»  Cooked  according  to  directions  on  tin — i  tablespoonful  first  mixed,  4  table- 
spoonfuls  of  cold  milk,  then  a  pint  of  boiling  milk  and  water  added  (i  water, 
§  milk).     All  the  rest  of  the  foods  were  cooked  with  water  alone. 


SPECIAL  COOKERS  407 

Slow  Cooking. 

Food  being  a  bad  conductor,  heat  only  penetrates  into  it  very 
slowly.  WolfFhiigel  and  Huppe,^  for  instance,  found  that  the 
temperature  of  the  interior  of  a  piece  of  meat  weighing  9  pounds 
after  four  hours'  boiling  was  only  88°  C,  or  12°  below  the  boiling- 
point  of  water.  The  interior  temperature  of  a  roast  varied  from 
70  to  95°  C,  according  to  size.  Similar  observations  have  been 
made  by  Sir  Henry  Thompson.^  He  found  that  the  temperature 
close  to  the  bone  of  a  leg  of  mutton  which  had  been  boiled  or  roasted 
for  some  hours  was  never  above  186°  or  187°  F. 

Hence  it  is  that,  if  heat  be  applied  to  a  piece  of  meat  too  rapidly, 
one  simply  wastes  fuel  and  runs  the  risk  of  overcooking  the  outer 
layers.  It  is  far  better  to  allow  a  moderate  amount  of  heat  to  act  on 
the  meat  for  several  hours,  and  the  longer  the  time  allowed,  the 
lower  will  be  the  temperature  required,  always  assuming  that  it  is 
kept  above  the  coagulation-point  of  proteins.  Various  special  forrns 
of  apparatus  have  been  invented  with  the  view  of  economizing 
fuel,  and  allowing  of  the  prolonged  action  of  a  moderate  degree  of 
heat,  some  of  which  are  certainly  not  as  well  known  as  they  deserve 
to  be. 

The  simplest  of  these  are  constructed  on  the  principle  of  an 
ordinary  water-bath,  and  consist  of  a  double  pan,  the  outer  being 
filled  with  water  which  is  kept  at,  or  near  to,  the  boiling-point,  while 
the  article  to  be  cooked  is  placed  in  the  inner  vessel.  The  heat  only 
penetrates  slowly  to  the  latter,  and  never  reaches  the  boiling-point, 
while  any  risk  of  burning  is  also  prevented.  The  French  bain-marie 
is-  constructed  on  this  plan.  Warren's  Cooking-pot  and  Bailey's 
Cookers^  are  also  good  examples  of  the  application  of  the  principle. 

The  Duplex  Boilerefte*  is  a  modification  of  the  bain-marie,  in  which 
the  steam  from  the  outer  pan  is  prevented  from  escaping  and 
reaches  a  high  temperature,  so  that  the  food  in  the  inner  vessel  can 
be  actually  boiled. 

Somewhat  different  from  these  is  the  Norwegian  Self-acting  Cooking 
Apparatus.^  This  consists  of  an  outer  cylindrical  vessel  lined  with 
non-conducting  material,  and  an  inner  metal  cylinder  in  which  the 
object  to  be  cooked  is  placed.  If,  for  example,  it  is  desired  to  boil  a 
fowl,  we  place  the  latter  in  a  saucepan  of  boiling  water,  boil  it  over 
the  fire  for  five  or  ten  minutes  in  order  to  'seal  up'  the  surface, 

1  Quoted  in  Bulletin  21,  United  States  Department  of  Agriculture. 

-  '  Food  and  Feeding,'  p.  97. 

"  l'>  liley's  Patent  Cookers  Company,  lo,  Bromley  Road,  Be  kenham,  Kent. 

*  Manufactured  by  R.  W.  Welbank,  North  Newington,  Banbury. 

•  Supplied  by  Silver  and  Co.,  Sun  Court,  Cornhill,  E.C. 


4o8  FOOD  AND  DIETETICS 

then  remove  the  pan  from  the  fire  and  place  it  in  the  inner  cylinder. 
The  outer  lid  is  then  closed,  and,  the  escape  of  heat  being  thus 
entirely  prevented,  cooking  is  allowed  to  go  on  slowly  for  several 
hours.  On  opening  the  apparatus  after  the  lapse  of  twelve  or 
eighteen  hours,  the  fowl  will  be  found  steaming  hot,  and,  though 
thoroughly  cooked,  quite  tender  throughout.  The  apparatus  acts 
on  the  principle  of  entirely  preventing  any  loss  of  heat,  and  just  as 
it  prevents  any  heat  getting  out,  so  it  can  with  equal  efficiency 
prevent  any  from  getting  in.  It  may,  therefore,  be  used  as  a 
refrigerator,  for  keeping  ices,  etc.,  unmelted,  quite  as  well  as  a  cooker. 
The  apparatus  saves  a  great  deal  of  time,  trouble,  and  fuel,  and  is 
very  useful  to  travellers  and  campers-out,  or  in  any  circumstances  in 
which  one  wants  hot  food  constantly  ready. 

A  little  reflection  will  show  that,  in  the  use  of  an  ordinary  oven,  a 
great  waste  of  fuel  is  inevitable,  for  the  metal  of  which  the  oven  is 
constructed  is  an  admirable  conductor,  and  allows  heat  to  escape  as 
fast  as  it  gets  in.  In  order  to  prevent  this  and  the  waste  of  fuel 
which  results  from  it,  all  that  is  necessary  is  to  have  the  oven 
covered  with  some  non-conducting  material.  The  heat  supplied  by 
the  fuel  will  then  be  unable  to  escape  from  the  oven,  and  will  all  be 
utilized  to  cook  the  food,  instead  of  being  to  a  large  extent  dissipated 
into  the  surrounding  atmosphere. 

An  oven  constructed  on  this  plan  was  devised  by  Canon  Moore 
EdeWor  use  in  the  preparation  of  penny  dinners.  The  apparatus 
and  its  advantages  are  thus  described  by  its  inventor  :2 

'  It  consists  of  a  box  3  feet  high,  2  feet  wide,  i  foot  g  inches  deep, 
with  an  outer  case  of  sheet  iron.  The  sides  and  lid  are  lined  with 
2|  inches  of  felt,  and  inside  this,  again,  is  a  further  lining  of  tin. 
Underneath  this  box,  which  will  hold  30  gallons,  are  placed  two 
of  Fletcher's  Atmospheric  Gas  Burners.  The  felt  being  a  non- 
conductor, nearly  all  the  heat  from  the  gas  is  utilized,  and  a  com- 
paratively small  expenditure  of  gas  suffices  to  raise  the  temperature 
of  the  contents  of  the  box  to  boiling-point,  or  to  the  heat  required  for 
the  food  which  is  being  cooked.^ 

*  When  once  the  desired  temperature  is  obtained,  one  of  the 
burners  can  be  turned  off  and  the  other  lowered,  when,  owing  to  the 
prevention  of  radiation  by  the  felt,  it  will  be  found  that  a  merely 
nominal  expenditure  of  gas  will  enable  the  temperature  to  be  main- 
tained for  hours,  and  even  when  the  gas  is  totally  extinguished 
many  hours  will  elapse  before  food  cooked  will  become  cool. 

^  Now  Dean  of  Worcester. 

*  'Cheap  Food  and  Cheap  Cooking'  (London  :  Walter  Scott),  1884. 
'  Since  the  above  was  written,  sundry  alterations  and  improvements  have  been 
made  which  considerably  increase  the  economy  and  efficiency  of  the  apparatus. 


EDE'S  APPARATUS  409 

*  But  except  in  the  case  of  puddings  which  require  rapid  boiling,  the 
cooking  is  done  in  an  inner  pan,  which  is  placed  inside  the  box,  and 
which  contains  rather  more  than  20  gallons.  The  apparatus  may  be 
best  described  as  a  huge  Warren's  pot,  with  the  additional  advantage 
that  the  whole  of  the  inner  pan  is  surrounded  by  warm  water. 

*  The  space  between  the  inner  pan  and  the  side  of  the  box  is  filled 
with  water,  which  is  kept  at  the  temperature  desired  by  means  of 
the  gas  burners. 

*  The  chief  advantages  of  this  apparatus  are  as  follows : 

*  Economy  in  first  cost  of  the  apparatus,  which  can  be  procured 
from  Messrs.  Emley  of  Newcastle. 

*  There  is  little,  if  any,  smell  of  cooking. 

*  The  apparatus  can  be  placed  in  any  room,  and  no  arrangement 
of  flues  is  required.  The  iron  pipe  which  takes  away  the  fumes  of 
the  gas  can  be  carried  into  the  chimney,  if  there  is  one  in  the  room, 
or,  if  there  is  no  chimney,  through  a  small  aperture  in  the  window. 

*  As  the  felt  retains  the  heat,  the  exterior  of  the  box  remains  cool, 
and  the  temperature  of  the  room  is  scarcely  affected ;  indeed,  so 
slight  is  the  smell  of  cooking,  so  little  the  heat  radiated,  that  the 
apparatus  might  almost  be  placed  in  the  schoolroom  itself. 

*  Owing  to  the  inner  tin  and  the  box  itself  being  firmly  closed,  no 
evaporation  takes  place,  and  all  the  nutriment  and  flavour  of  the 
food  is  preserved. 

*  Surprising  though  it  may  sound,  there  is  a  gain  of  nearly  30  per 
cent,  in  quantity  in  the  case  of  meat  cooked  in  this  way ;  in  pre- 
paring soup  less  of  the  nutrition  of  the  meat  is  lost,  and  vegetables 
are  more  palatable  as  well  as  more  nutritious  when  cooked  in  the 
manner  described. 

*  Most  food  is  improved  by  being  cooked  very  slowly ;  this  can  be 
easily  done  by  this  apparatus,  and  also  it  can  be  so  adjusted  that 
each  kind  of  food  can  be  cooked  at  the  temperature  which  most 
effectively  brings  out  its  nutritious  qualities ;  this  for  meat  is  at 
about  170°  F.,  for  pulse  about  200°. 

*  The  expenditure  for  fuel  is  very  slight ;  gas  costing  seven-tenths 
of  a  penny  will  in  this  apparatus  raise  5  gallons  of  water  to  boiling- 
point,  and  less  than  3d.  is  sufficient  to  boil  30  gallons.  Once  boiled, 
the  temperature  can  be  retained  at  a  nominal  expenditure  of  gas. 

'  Another  advantage  is  that  no  food  can  be  burned,  and  no  care  is 
required  to  prevent  that  very  common  catastrophe.  The  food  once 
placed  in  the  inner  tin  in  proper  proportions,  and  the  space  between 
the  inner  and  outer  case  filled  with  water,  the  lid  is  closed  and  the 
gas  turned  on  till  the  required  temperature  is  reached ;  it  is  then 


410 


FOOD  AND  DIETETICS 


'^^^m^^^m^  f^-^m^^ 


.'•; ^r~^ — = \~? "^ '^ 


lowered,  and  the  dinner  is  left  to  take  care  of  itself.  As  it  is  often 
convenient  to  prepare  the  dinner  the  previous  afternoon,  it  is  not 
unfrequently  left  cooking  at  a  Jow  temperature  the  whole  night.  All 
the  labour  entailed  by  keeping  up  a  coal  fire  is  avoided,  and  also  the 
constant  attention  usually  necessary  to  prevent  burning. 

'The  only  defect  of  the  apparatus  is  that  it  is  not  capable  of 
baking,  but  in  the  case  of  school  dinners  I  think  this  will  be  found 
of  little  consequence.' 

The  Aladdin  Oven,  invented  by  Dr.  Edward  Atkinson,  is  on  the 

same  principle.  *  It  is  a  simple 
iron  box,  closed  in  front  by  a  door, 
and  having  an  opening  in  the  top 
that  communicates  with  a  tube  to 
let  off  any  superfluous  steam.  This 
box  is  surrounded  by  another,  whose 
top  and  sides  are  made  of  non-con- 
ducting material  for  the  purpose  of 
holding  the  heat.  "  A  standard,  on 
which  this  box  is  set,  and  a  lamp 
underneath  complete  the  apparatus.'^ 
A  clearer  idea  of  the  structure  of 
the  oven  will  be  obtained  from  the 
accompanying  diagram,  borrowed 
from  Dr.  Atkinson's  interesting  book 
(Fig.  32). 

The  oven  can  be  heated  either  by 
a  kerosene  lamp  or  by  a  small  gas 
burner,  and  it  will  raise  the  tempera- 
ture of  40  pounds  of  meat  and  15 
quarts  of  water  to  180°  F.  in  the 
space  of  seven  hours,  and  if  the  lamp 
is  then  removed  the  temperature  undergoes  no  appreciable  diminu- 
tion for  fully  four  hours. 

Dr.  Atkinson  calculates  that  in  an  ordinary  oven  2  pounds  of  fuel 
must  be  expended  for  every  pound  of  food  cooked,  whereas  in  his 
apparatus  2^  pounds  of  fuel  will  cook  60  pounds  of  food,  and  that 
the  daily  cost  of  cooking  by  it  amounts  to  only  ^d.  per  person  for  a 
family  of  ten.  The  saving  of  trouble  also  is  enormous,  for  the 
apparatus  can  be  left  to  cook  by  itself  overnight. 

'  Edward  Atkinson,  '  The  Science  of  Nutrition  and  the  Art  of  Cooking  in  the 
Aladdin  Oven '  (Boston,  Damrell  and  Upham),  1896.  See  also  *  How  to  Maka 
RBd  y^  an  Aladdin  Oven,'  by  tha  same  author  and  publisher  (1901). 


Fig.  32. — The  Aladdin  Oven. 
(After  Atkinson.) 


THE  ALADDIN  OVEN  411 

In  i88g  and  1890  a  number  of  experiments  were  made  in  America 
by  Mrs.  Ellen  H.  Richards  and  Mrs.  Mary  H.  Abel  on  the  best 
methods  of  cooking  food.  They  state  in  their  report^  that  'for 
simplicity,  effective  use  of  heat,  economy  of  fuel  and  development  of 
flavour  in  the  food  cooked,  combined  with  increase  of  its  digestibility, 
the  Aladdin  Oven  is  an  apparatus  far  exceeding  in  merit  any  other 
now  in  the  market.'  A  friend  of  the  writer's  has  used  the  oven  for 
several  years  with  the  most  satisfactory  results,  and  his  experience 
entirely  bears  out  the  favourable  opinion  expressed  in  the  above 
report.  The  Aladdin  Oven  cannot  be  obtained  ready  made  in  this 
country,  but  it  can  easily  be  constructed  by  any  intelligent  tinsmith. 

It  is  interesting  to  note  that  the  advantages  of  slow  cooking  are 
well  known  to  some  savage  tribes,  and  in  this  respect  the  civihzed 
cook  has  something  to  learn  from  them. 

This  is  the  method  of  cooking  practised  by  the  Kanakas  of  the 
Friendly  Islands,  as  described  by  the  late  Mr.  F.  T.  BuUen  :' 

*  A  hole  is  scooped  in  the  earth,  in  which  a  fire  is  made  (of  wood), 
and  kept  burning  until  a  fair-sized  heap  of  glowing;  charcoal  remains. 
Pebbles  are  then  thrown  in  until  the  charcoal  is  covered.  Whatever 
is  to  be  cooked  is  enveloped  in  leaves,  placed  upon  the  pebbles,  and 
more  leaves  heaped  upon  it.  The  earth  is  then  thrown  back  into 
the  cavity  and  well  stamped  down.  A  long  time  is,  of  course, 
needed  for  the  viands  to  get  cooked  through  ;  but  so  subtle  is  the 
mode  that  overdoing  anything  is  almost  an  impossibility.  A  couple 
of  days  may  pass  from  the  lime  of  *  putting  down  '  the  joint,  yet 
when  it  is  dug  up  it  will  be  smoking  hot,  retaining  all  its  juices, 
tender  as  jelly,  but,  withal,  as  full  of  flavour  as  it  is  possible  for 
cooked  meat  to  be.  No  matter  how  large  the  joint  is  or  how  tough 
the  meat,  this  gentle  suasion  will  render  it  succulent  and  tasty ;  and 
no  form  of  civilized  cookery  can  in  the  least  compare  with  it.* 

No  better  illustration  of  the  advantages  of  slow  cooking  could  well 
be  found. 

1  Bulletin  No.  21,  United  States  Department  of  Agriculture,  p.  94, 

•  'The  Cruise  of  the  Cachalot '  (London  :  Smith,  Elder  and  Co  ),  p.  273. 


[412   ] 


CHAPTER  XXIII 

THE  DIGESTION  OF  FOOD  IN  HEALTH 

The  object  of  the  present  chapter  is  to  consider  the  bearing  of  some 
physiological  facts  upon  such  matters  as  the  selection  of  foods,  the 
arrangement  of  meals,  and  other  practical  questions  in  dietetics.  It 
will  be  convenient  to  arrange  the  principal  facts  under  separate 
headings. 

Digestion  in  the  Mouth. 

The  mouth  stage  of  digestion  is  mainly  a  mechanical  one,  and  its 
object  essentially  protective.  By  reducing  the  food  to  a  pulp,  by 
breaking  up  and  softening  hard  particles,  by  neutralizing  or  diluting 
irritating  constituents,  such  as  acids,  and  by  surrounding  the  whole 
mass  with  a  wrapping  of  mucus,  it  is  sought  to  guard  the  stomach 
against  the  effects  of  the  ingestion  of  injurious  substances.  In  the 
accomplishment  of  this  object  thorough  chewing  is  of  the  first 
importance,  and  if  the  food  is  to  be  thoroughly  chewed  it  must  be 
eaten  slowly.^  To  'bolt'  the  food  in  the  manner — as  it  has  been 
described — in  which  one  posts  letters  interferes  gravely  with  proper 
disintegration  ;  and  many  a  case  of  dyspepsia,  too,  is  kept  up,  if  not 
actually  produced,  by  imperfections  of  the  teeth. 

At  the  same  time,  it  must  not  be  forgotten  that  there  is  a  chemical 
side  to  mouth  digestion  as  well.  Starch,  under  the  action  of  the 
ptyalin  in  the  saliva,  and  by  processes  which  need  not  here  be 
described,  is  converted  into  soluble  substances.  The  degree  to  which 
this  occurs  varies,  partly  with  the  form  of  the  starch  grain,  and  partly 
with  the  consistence  of  the  food  and  the  reaction  of  the  medium. 

Some  forms  of  starch — e.g.,  that  of  rye  and  maize — are  much  more 
readily  acted  upon  by  the  saliva  than  others,  such  as  potato  starch ; 
raw  starch,  owing  to  the  cellulose  coating  of  its  grains,  is  hardly 
affected  at  all. 

^  Attention  has  in  recent  times  been  called  to  the  great  importance  of  thorough 
mastication  by  the  experiments  and  observations  of  Mr.  Horace  Fletcher,  who 
has  proved  not  only  how  greatly  very  prolonged  chewing  facilitates  digestion, 
but  also  that  if  the  process  is  carried  out  sufficiently  thoroughly  the  appetite 
and  requirements  of  the  body  are  satisfied  by  much  less  food  than  the  amount 
usually  taken.  For  a  description  of  his  method  see  a  paper  by  Dr.  Hubert  Higgins 
('  Is  Man  Poltophagic  or  Psomophagic  ?'),  Lancet,  1905,  i.  1334,  1417. 


DIGESTION  IN  THE  MOUTH  4^3 

Porous  foods,  into  which  the  saliva  can  readily  penetrate,  are 
more  easily  attacked  than  dense  and  compact  masses  of  food,  such 
as  new  bread.  Moist  substances,  too,  offer  less  resistance  than 
those  which  are  dry.  As  regards  this  matter  Pereira  has  pointed 
out  an  analogy  in  the  preparation  of  tinctures  by  percolation,  the 
substance  to  be  extracted  being  much  more  readily  acted  upon  if  it 
has  been  subjected  to  a  preliminary  moistening.  In  accordance  with 
this,  it  has  been  found  that  dry  bread,  taken  alone,  is  digested  to  a 
much  smaller  extent  in  the  mouth  than  if  it  be  eaten  along  with 
water.  A  natural  provision  is  made  for  the  larger  amount  of  ptyalin 
required  for  the  digestion  of  dry  foods,  for  Pawlow  found,  in  his 
experiments  on  dogs,  that  such  articles  caused  a  much  greater  reflex 
flow  of  saliva  than  moist  foods  did.  The  latter,  indeed,  seemed 
hardly  to  provoke  any  flow  of  saliva  at  all.  We  have  here  a  con- 
firmation of  the  view  that  the  uses  of  the  saliva  are  mainly 
mechanical,  for  the  object  of  the  increased  flow  is  apparently  to 
moisten  the  dry  food,  even  more  than  to  digest  its  starch. 

In  describing  the  influence  of  such  articles  as  vinegar,  malt  liquors, 
and  wines,  on  salivary  digestion,  it  was  pointed  out  how  marked 
was  the  retarding  effect  of  the  acids  which  these  fluids  contain  upon 
the  action  of  ptyalin,  and  the  same  was  found  to  hold  good  for  the 
tannic  acid  in  tea.  It  must  be  noted,  however,  that  the  merely 
chemical  effect  of  these  beverages  may  be  to  a  large  extent  counter- 
acted by  the  more  profuse  flow  of  saliva  which  they  often  induce. 
All  sour  fluids  possess  this  property,  and  the  warmth  of  tea  and 
the  bitter  ingredients  of  beer  enable  them  to  exert  a  similar  effect. 
Wines,  however,  do  not  seem  to  be  powerful  sialogogues,  though  some 
of  them,  e.g.,  sherry,  excite  a  more  abundant  secretion  of  mucus.^ 

Another  import^t  use  of  saliva  which  must  never  be  forgotten  is 
that  of  washing  the  mouth  clean  from  food  particles,  which  would 
otherwise  remain  between  the  teeth  and  undergo  decomposition.  So 
important  is  this  hygiene  of  the  mouth  in  the  prevention  of  dental 
caries  that  many  dental  surgeons  advise  that  a  meal  should  always 
end  with  raw  fruit,  which  stimulates  a  flow  of  saliva,  besides  having 
in  itself  cleansing  properties  in  virtue  of  its  acid  juices.^ 

Digestion  in  the  Stomach. 

Just  as  the  chief  object  of  digestion  in  the  mouth  is  to  protect  the 

stomach,  so  the  chief  object  of  digestion  in  the  stomach  is  to  protect 

the  intestine.    Observations  of  the  results  of  complete  removal  of  the 

'»  See  Aitchison  Robertson,  'The  Salivary  Digestion  of  Starch  in  Simple  and 
Mi>ed  Diets,'  Journal  of  Anatomy  and  Physiology,  1898,  xxxii.  615. 
-  Sira  Wallace,  Lancet,  i.,  1915,  p.  1229, 


414  FOOD  AND  DIETETICS 

stomach  in  man  have  shown  that  its  co-operation  cannot  be  regarded 
as  essential  to  the  complete  digestion  and  absorption  of  an  ordinary 
mixed  diet,  provided  the  latter  be  presented  to  the  intestine  in  a 
suitable  mechanical  form.^ 

The  chief  functions  of  the  stomach,  indeed,  are  probably  these  '.'■^ 

1.  To  act  as  a  reservoir. 

2.  To  reduce  the  food  to  a  semi-fluid  form. 

3.  To  sterilize  the  food — at  least  in  part. 

4.  To  regulate  its  temperature. 

5.  To  effect  a  slight  degree  of  absorption. 

We  shall  briefly  consider  each  of  these  functions  separately. 

I.  By  acting  as  a  reservoir,  the  stomach  enables  us  to  take  our 
food  in  considerable  quantities  at  a  time ;  i.e.,  it  renders  meals 
possible.  The  practical  convenience  of  this  needs  no  demonstration, 
but  some  other  points  connected  with  the  question  of  meals  require 
to  be  raised. 

And  first  it  may  be  asked.  At  what  intervals  should  meals  be 
taken  ?  Is  it  better  to  take  several  small  meals,  or  to  consume  one's 
daily  supply  of  food  at  one  or  two  sittings  ?  The  reply  undoubtedly 
is  that  several  small  meals  are  best.  The  *  one-meal-a-day  man  '  is 
at  a  double  disadvantage  :  (i)  he  is  apt  to  overburden  the  mechanical 
powers  of  his  stomach  by  the  mere  weight  of  food  introduced  into  it 
at  one  time ;  (2)  some  of  the  constituents  of  food  so  introduced  are 
partly  wasted,  owing  to  the  assimilative  powers  of  the  tissues  being 
unable  to  keep  pace  with  the  flood  of  nutriment  which  reaches  them 
all  at  once.     Let  us  consider  each  of  these  points  for  a  moment. 

(i)  The  capacity  of  the  human  stomach  is  very  variable,  both  in 
different  individuals  and  in  the  same  individual  at  different  periods 
of  life.  On  the  average  it  may  be  put  down  as  from  2  to  4  pints,^  and 
in  the  case  of  solids  at  about  2  pounds.  If  it  be  remembered  that 
the  total  amount  of  solid  food  required  daily  is  at  least  3  pounds, 
it  is  evident  that  if  one  were  to  take  the  whole  of  this  in  one  meal 
he  would  be  apt  to  overtask  the  powers  of  the  stomach,  or  to 
produce  a  gradual  dilatation  of  the  organ.  In  the  case  of  persons  of 
feeble  digestive  power  the  limitation  of  the  bulk  of  meals  is  of  even 
greater  importance.     For  them  *  little  and  often '  is  the  golden  rule. 

(2)  There  is  evidence  to  show  that  more  food  is  wasted  when  it  is 
all  taken  at  once  than  when  it  is  spread  over  a  considerable  time. 
The  waste  chiefly  affects  the  proteins,  which  are  the  most  rapidly 

*  Schlatter,  Lancet,  1898,  1.  141. 

'  An  additional  function  is  the  establishment  of  osmotic  equilibration  between 
the  blood  and  the  fluid  food.  See  Jona,  '  The  Osmotic  Pressure  of  Liquid  Foods  ' 
{Bio-Chemical  Joum.,  1909,  iv.  462). 

*  See  Gillespie,  'The  Natural  History  of  Digestion,'  p.  274,  and  the  same 
author's  'Modern  Gastric  Methods,'  p.  3,  1899. 


ARRANGEMENT  OF  MEALS  415 

digested  of  the  constituents  of  the  food,  and  is  partly  due  to  defective 
absorption  and  increased  opportunity  for  intestinal  putrefaction. 
Ranke,  for  instance,  found  that  if  he  ate  1,800  grammes  of  meat 
all  at  once  the  loss  by  the  bowel  amounted  to  12  per  cent.,  but 
if  the  same  quantity  of  meat  was  divided  into  three  meals  the  waste 
was  only  5  per  cent.  The  loss  of  protdn  must  also  be  attributed  in 
part  to  defective  assimilation.  If  the  tissues  are  so  flooded  with 
protein  that  they  are  unable  to  assimilate  the  whole  of  it,  the  excess 
appears  to  be  rapidly  excreted  in  the  form  of  urea  instead  of  being 
stored  up.  This,  at  least,  was  the  conclusion  which  Krummacher* 
drew  from  his  experiments  on  dogs,  in  which  he  tested  the  effects  of 
giving  a  certain  quantity  of  food  in  one  meal,  and  then  when  divided 
into  five  meals.  He  found  that  more  nitrogen  was  excreted  in  the 
former  case  than  in  the  latter.  It  follows  from  this  that  care  must 
be  taken  not  only  to  have  enough  total  protein  in  the  diet,  but  to 
see  that  it  is  evenly  spread  over  the  day,  so  that  the  tissues  may 
not  at  one  time  be  repleted  and  at  another  be  compelled  to  draw  on 
their  own  reserves.  The  tissues,  in  fact,  may  be  compared  to  a 
reservoir,  the  outflow  from  which  is  pretty  constant,  and  to  which, 
if  it  is  to  be  kept  full,  the  inflow  should  also  be  fairly  steady.  A 
practical  example  of  the  neglect  of  this  principle  is  thus  given  by 
Clement  Dukes  (he  is  speaking  of  the  unwise  division  of  meals  often 
observed  at  public  schools) :  2 

*  For  instance,  if  bread-and-butter  only  be  provided  for  breakfast, 
say  at  8  a.m.,  this  will  be  digested  and  used  up  by  the  system  long 
before  dinner  takes  places  at  1.30  p.m.,  and  therefore  from  about 
II  a.m.  to  1.30  p.m.  the  body  will  be  starved.  Then  at  dinner  the 
boy  can  only  eat  a  certain  amount  of  food,  however  much  the 
caterer  may  supply,  and  thus  the  defect  of  the  two  hours  and  a 
half  of  starvation  is  never  recovered,  although  growth  must  take 
place  all  the  same.' 

The  hours  of  meals  have  varied  greatly  even  in  the  same  country 
at  difTerent  periods  of  history,  and  must  depend  largely  upon  con- 
venience and  upon  habits  as  regards  work,  etc.  If  possible,  dinner, 
the  principal  meal  of  the  day,  should  be  taken  after  work  is  over,  so 
that  comparative  repose  may  be  enjoyed  after  it.  As  a  matter  of 
actual  observation,  Voit  found  that  50  per  cent,  of  the  day's  protein, 
61  per  cent,  of  its  fat,  and  32  per  cent,  of  its  carbohydrate,  was  taken 
at  dinner. 

2.  The  second  function  of  the  stomach  is  to  reduce  the  food  to 
a  semi-fluid  form.     This  is  done  partly  by  the  solvent  action  of  the 

1  '  Wie  beeinflusst  die  Vertheilung  der  Nahrung  auf  mebrere  MahUeiten  die 
Eiweisszersetzung?'  Zeit.  f.  Biolog.,  1897,  xxxv.  481. 

*  '  School  Diet/  second  edition,  p.  9< 


4i6  FOOD  AND  DIETETICS 

gastric  juice,   and   partly   by   the   mechanical    movements   of  the 
stomach  walls.     We  may  therefore  glance  for  a  moment  at — 

The  Secretion  of  Gastric  Juice. 

Until  recent  times  it  was  supposed  by  physiologists  that  the 
secretion  of  gastric  juice  was  chiefly  brought  about  by  mechanical 
stimulation  of  the  mucous  membrane  of  the  stomach  by  the  particles 
of  food  introduced  into  it.  The  elaborate  and  ingenious  experiments 
of  Pawlow,^  however,  have  shown  that  this  is  a  mistake,  and  that 
the  chief  factors  concerned  in  bringing  about  the  secretion  are 
(i)  psychical  and  (2)  chemical,  and  that  mechanical  action  plays 
quite  a  secondary  part,  if,  indeed,  it  comes  in  at  all. 

The  psychical  factor  is  intimately  bound  up  with  the  sensations 

of  appetite  and  hunger.     It  is  difficult  to  define  these  terms  exactly, 

though  appetite  may  be  described  as  the  desire  for  food,  and  hunger 

as  the  need  for  it.^     Appetite  is  dependent  partly  upon  hunger — as 

Von  Noorden  has  it,  it  is  to  be  regarded  as  '  the  reflection  of  the 

Calorie-requirements  of  the  tissues ' — but  partly  also  upon  the  state 

of  the  stomach  and  alimentary  tract  generally.     Thus,  an  individual 

may  complain  of  '  hunger '  even  although  the  stomach  is  full,  as  in 

those  cases  where  a  fistula  exists  high  up  in   the  intestine,  and 

prevents  the  food  from  reaching  the  tissues  ;^  or  the  stomach  may 

be   quite   empty,  and   yet   no  complaint  of  hunger   made,  as,  for 

example,  in  the  case  of  patients  who  are  being  fed  per  rectum.     In 

disease  of  the  stomach,  too,  or  where  it  is  in  a  state  of  functional 

anaesthesia,  appetite  may  be  in  abeyance,  although  the  need  for  food 

('  tissue  hunger ')  exists.     In  such  a  case  the  introduction  of  food 

into  the  stomach  may  suddenly  awaken  appetite.    Pawlow  mentions 

a  good  example  of  this  in  his  own  experience.    He  was  convalescent 

from  a  trifling  illness,  and  in  spite  of  some  days'  abstention  from 

food  still  suffered  from  complete  loss  of  appetite.    He  then  swallowed 

'  '  Die  Arbeit  der  Verdauungsdrusen,*  Wiesbaden,  1898.  Pawlow's  chief 
results  have  been  confirmed,  in  the  case  of  the  human  subject,  by  Schiile  ('  In 
wie  Weit  Stimmen  die  Experiraente  von  Pawlow  am  Hunde  mit  den  Befunden 
am  normalen  menschlichen  Magen  ueberein  ?'),  Deut.  Arch./.  Klin.  Med.,  1901. 
Ixxi.  III. 

*  This  probably  does  not  cover  the  whole  difference  between  appetite  and 
hunger.  The  sensation  of  pleasure  seems  inseparable  from  the  former,  that  of 
pain  from  the  latter.  Appetite  is  more  particularly  related  to  the  stomach,  and 
has  its  seat  in  the  brain  cortex.  Hunger  appears  to  be  more  connected  with  the 
nutritive  needs  of  the  tissues,  and  possibly  affects  more  the  centres  which  preside 
over  organic  life.  There  is  reason,  too,  to  believe  that  the  sensation  of  hunger 
is  peculiarly  associated  with  a  deficiency  of  proteins  in  the  blood,  and  can  only 
be  really  allayed  by  a  supply  of  them  in  the  food.  Fat,  on  the  other  hand,  seems 
to  have  a  special  power  of  appeasing  appetite.  Advantage  of  this  fact  has  been 
taken  by  Oertel  in  his  dietary  for  the  treatment  of  obesity  (see  p.  484). 

*  For  a  description  of  such  a  case  see  Busch.  Virchow'i  Archiv.,  iS^S,  xiv.  140. 


APPETITE  AND  HUNGER'  4^7 

a  glass  of  wine,  and  immediately  a  strong  desire  for  food  arose. 
This  is  a  case  in  which  Vappetit  vient  en  mangeani. 

While,  then,  appetite  can  hardly  exist  without  some  degree  of 
hunger,  the  latter  may  be  present  without  the  accompaniment  of 
the  former.  In  health,  however,  the  two  seem  to  co-exist,  and 
appetite  is  a  true  index  of  the  amount  of  nutriment  required  by  the 
tissues.  It  may  be  that  some  people,  otherwise  healthy,  have 
habitually  less  appetite  than  corresponds  to  the  true  needs  of  their 
tissues,  and  this  may  explain  some  cases  of  malnutrition.  Von 
Noordeni  is  of  opinion  that  this  state  of  things  may  be  brought 
about  by  defective  feeding  in  childhood,  i.e.,  by  the  use  of  food  which 
does  not  make  sufficient  demand  upon  the  digestive  powers,  and 
allows  the  stomach  and  intestines  to  grow  up  in  a  condition  of 
functional  feebleness.  Hence  in  after-life,  when  compact  and  highly 
nourishing  food  cannot  be  obtained,  a  more  bulky  diet  satisfies  the 
stomach  before  the  needs  of  the  tissues  are  really  supplied.  For 
this  reason,  also,  such  persons  are  often  poor  eaters  of  fat,  for  it  is 
difficult  to  take  much  fat  without  repugnance  in  a  mainly  animal 
form,  but  comparatively  easy  when  diluted  with  a  large  bulk  of 
vegetable  food. 

This  discussion  has  led  us  away  somewhat  from  our  starting- 
point — the  relation  of  appetite  to  the  secretion  of  gastric  juice. 
The  experiments  of  Pawlow,  already  mentioned,  have  shown  that 
appetite  is  the  most  powerful  excitant  of  gastric  secretion.  The 
mere  sight  or  smell  of  food  and  the  act  of  chewing  are  followed,  if 
appetite  be  present,  by  a  profuse  flow  of  a  peculiarly  powerful  gastric 
juice  which  may  continue  for  as  long  as  four  hours.  Hence  the 
importance  for  digestion  of  such  aesthetic  aids  to  appetite  as  agreeable 
surroundings,  a  well-appointed  table  and  good  cooking,  and  the  use 
before  dinner  of  such  ticklers  of  the  palate  as  '  sherry  and  bitters  *  or 
the  savoury  articles  usually  classed  on  the  menu  as  hors  d'auvres.^ 

The  other  factor  mainly  concerned  in  producing  gastric  secretion 
is  a  chemical  one,  the  active  agents  being  the  chemical  constituents 
of  the  food.  The  remarkable  fact  has  recently  been  elicited  that 
the  stimulus  so  exerted  is  not  a  general,  but  a  specific  one,  each  food 
calling  forth  a  supply  of  those  ingredients  of  the  juice  specially 
required  for  its  own  digestion.  Some  easily  dissolved  foods,  for 
example,  such  as  meat,  produce  a  flow  of  juice  large  in  quantity, 
but  poor  in  ferments  ;  other  foods,  such  as  bread,  which  are  more 
difficult  of  solution,  cause  a  scanty  but  very  concentrated  juice  to  be 

1  Berliner  Klinik.,  1893,  vi.,  Heft  55. 

'  It  is  an  important  fact,  however,  that  the  human  stomach  appears  to  be 
capable  of  digesting  even  in  the  absence  of  all  psychical  influences— £.;^.,  if  food 
be  introduced  into  it  without  the  subject's  knowledge  (see  Schiile,  op.  cit.). 

27 


4i8  FOOD  AND  DIETETICS 

secreted  which  is  \  ery  rich  in  ferment ;  milk,  again,  which  is  one  of 
the  most  easily  digested  of  all  foods,  produces  only  a  moderate 
amount  of  juice,  and  that  of  weak  digestive  power. 

This  capability  of  foods  to  bring  about  the  secretion  of  a  specific 
kind  of  gastric  juice  specially  adapted  to  the  requirements  of  their 
own  digestion  is  of  importance  for  this  reason,  that  it  enables 
'  digestive  habits '  to  be  very  readily  established.  Let  us  suppose, 
for  instance,  that  a  patient  has  been  confined  for  some  time  to  an 
exclusively  milk  diet.  His  stomach  soon  acquires  the  habit  of 
manufacturing  a  secretion  specially  adapted  for  the  digestion  of 
milk.  But  this,  as  we  have  seen,  happens  to  be  a  secretion  of 
small  digestive  power.  If  the  diet  be  now  changed  to  one,  say, 
chiefly  composed  of  bread,  some  time  may  elapse  before  the  specific 
secretion  specially  suited  to  the  digestion  of  bread  is  established, 
and  meanwhile  dyspepsia  may  result.  This  may  explain  why 
sudden  changes  of  diet  are  to  be  avoided. 

*  If,'  says  Pawlow,^  '  one  alters  the  diet  of  an  animal  and  goes  on 
giving  the  new  food,  one  finds  that  the  ferments  contained  in  the 
digestive  juices  accommodate  themselves  more  and  more  every  day 
to  the  altered  diet.  If,  for  example,  one  feeds  a  dog  for  some  weeks 
on  milk  and  bread  only,  and  then  changes  to  a  purely  meat  diet,  which 
contains  much  more  protein  and  almost  no  starch,  one  observes  a 
gradual  increase  in  the  protein  ferments  of  the  pancreatic  juice. 
The  capability  of  digesting  protein  increases  day  by  day,  whilst, 
conversely,  the  starch-digesting  power  falls  off.  This  adaptation 
takes  place  much  more  readily  in  some  animals  than  in  others. 
Where  it  does  not  easily  occur,  a  sudden  change  of  diet  may 
produce  considerable  digestive  disturbances.' 

In  the  light  of  these  facts  one  can  understand  the  enormous 
importance  of  establishing  good  'digestive  habits'  in  the  young. 
If  a  child  is  encouraged  to  avoid  fat,  for  example,  he  may  ultimately 
lose  the  power  of  producing  the  secretion  specially  suited  to  the 
digestion  of  fatty  foods,  and  may  thus,  with  the  best  intentions,  be 
unable  to  eat  much  fat  all  his  life  afterwards,  and  so  suffer  from 
impaired  nutrition.  This  is  the  more  to  be  regretted  as  there  is 
reason  to  believe  that  inability  to  digest  fat  renders  one  peculiarly 
liable  to  become  the  victim  of  tuberculous  diseases. 

Curiously  enough,  it  is  not  all  chemical  constituents  of  the  food 
which  are  capable  of  exciting  a  secretion  of  gastric  juice.  Egg- 
white,  for  instance,  produces  none,  nor  do  the  albumoses,  peptone, 
starch  or  sugar  ;  milk,  gelatin,  and  water  produce  slight  secretion, 
while  the  extractives  of  meat  are  amongst  the  most  powerful  excitants 

'  0/.  cit.,  p.  52. 


ACIDITY  OF  THE  GASTRIC  JUICE  419 

known.  Soup  makes  a  good  beginning  to  a  meal,  because  it  stimulates 
a  flow  of  gastric  juice,  not  only  by  its  warmth,  but  also  by  virtue  of  the 
gelatin  and  extractives  of  meat  which  it  contains. 

On  the  other  hand,  fat  seems  actually  to  restrain  the  secretion  of 
gastric  juice  even  when  other  foods  are  present  as  well.  This  is 
no  doubt  one  reason  why  fat  things  are  difficult  to  digest,  and  why 
skim  milk  is  '  lighter '  than  milk  rich  in  cream.  It  teaches  us  also 
that  such  articles  as  cod-liver-oil  should  be  given  some  time  after 
meals,  when  the  gastric  juice  has  been  already  poured  out. 

Acidity  of  the  Gastric  Contents. 

The  total  amount  of  hydrochloric  acid  present  in  the  stomach 
depends  upon  the  quantity  of  gastric  juice  secreted.  The  proportion 
of  acid  present  in  the  juice  is  very  constant  in  the  same  individual. 
In  different  persons,  however,  it  varies  from  about  i  to  2|-  parts  per 
1,000  of  juice.  The  cause  of  these  individual  differences  is  not  quite 
clear,  but  they  seem  to  depend  to  some  extent  upon  the  kind  of  food 
habitually  taken,  persons  who  live  largely  upon  meat  having  usually 
a  more  acid  juice  than  those  who  partake  more  freely  of  vegetables.^ 
This  is  another  example  of  the  establishment  of  a  '  digestive  habit,* 
to  which  reference  has  already  been  made. 

The  total  amount  of  acid  present  in  the  stomach  rises  gradually 
during  the  first  three-fourths  of  the  period  occupied  by  the  digestion 
of  a  meal,  and  then  falls  off  rapidly  during  the  remaining  fourth. 
The  fall  in  acidity  is  probably  to  be  explained  by  the  pouring  out 
towards  the  end  of  digestion  of  a  neutral  or  slightly  alkaline  juice 
from  the  pyloric  end  of  the  stomach. 

Of  the  total  amount  of  acid  present  in  the  gastric  contents  at  any 
moment,  only  a  small  part  exists  in  the  free  form ;  the  larger  part  is 
in  a  state  of  combination.  The  hydrochloric  acid  first  poured  out 
is  fixed  by  any  bases  which  may  be  present  in  the  food  {e.g.,  car- 
bonates and  lactates),  and  after  these  have  been  neutralized  the 
proteins  of  the  food  lay  hold  of  the  rest  of  the  acid  and  enter  into 
organic  combination  with  it,  and  it  is  only  after  these  have  been 
saturated  that  the  acid  is  able  to  make  its  appearance  in  the  stomach 
in  a  free  form.  The  exact  moment  at  which  this  occurs  must  ob- 
viously vary  greatly  with  the  amount  of  food  in  the  stomach  and 
the  proportion  of  protein  which  it  contains.  The  larger  the  meal 
and  the  richer  it  is  in  proteins,  the  longer  will  the  appearance  of 

*  See  Verhaegen,  '  Physiologic  et  Pathologie  de  la  Secretion  Gastrique,'  Paris, 
1898,  p.  9  ;  alsc  Gillespie,  '  The  Natural  History  of  Digestion,'  p.  io6.  Schule, 
however,  found  that  the  kir.d  of  food  has  very  little  influence  on  the  percentage 
of  acid  in  the  gasiric  juice  {pp.  cit.). 


420  FOOD  AND  DIETETICS 

free  acid  in  the  stomach  be  delayed.  As  an  illustration  of  this,  the 
following  observations  of  Penzoldt^  may  be  cited  : 

After  7  or  8  ounces  of  sweetbread  free  acid  was  present  in  one 
hour. 

After  7  or  8  ounces  of  chicken  free  acid  was  present  in  two  hours. 

After  7  or  8  ounces  of  beef- steak  free  acid  was  present  in  three 
hours. 

After  5^  ounces  of  vegetable  food,  free  acid  was  usually  found  in 
one  or  one  and  a  half  hours  ;  but  if  the  food  was  one  very  rich  in 
protein,  e.g.,  peas  or  lentils,  its  appearance  was  delayed  for  three 
hours  or  more. 

The  amount  of  free  acid  present  does  not  usually  exceed  i  part  in 
i.ooo  of  the  stomach  contents,  and  its  presence  persists  for  about 
one  and  a  half  hours.  We  must  now  briefly  consider  the  relations 
of  the  acidity  of  the  stomach  (i)  to  the  gastric  digestion  of  starch  ; 
(2)  to  morbid  gastric  sensations. 

Digestion  of  Starch  in  the  Stomach. 

There  is  no  doubt  that  ptyalin  is  rapidly  killed  by  free  hydro- 
chloric acid,  and  even  if  o-i  per  cent,  is  present  its  action  on  starch 
ceases  entirely.  The  effect  of  combined  hydrochloric  acid  on  the 
ferment,  however,  is  by  no  means  so  certain,  and  the  experiments 
of  different  authorities  on  the  subject  have  yielded  very  discordant 
results,*  but  it  seems  to  be  generally  agreed  that  the  presence 
of  anything  like  a  large  amount  of  combined  acid  is  highly 
inimical  to  the  conversion  of  starch.  It  follows  from  this  that  the 
digestion  of  starch  in  the  stomach  is  not  likely  to  continue  for  more 
than  half  an  hour — or  at  most  one  hour — after  the  taking  of  a  meal. 
Obviously,  the  process  can  go  on  longer  the  greater  the  proportion 
of  hydrochloric  acid  which  passes  into  the  combined  form  ;  in  other 
words,  the  presence  of  a  large  amount  of  protein  in  the  food  is 
favourable  to  the  digestion  of  starch  in  the  stomach,  whereas  if  the 
meal  consists  exclusively  of  carbohydrates  the  process  must  sooner 
come  to  an  end.  This  is  one  of  the  many  advantages  of  a  mixed 
diet. 

Observations  with  the  X  rays  have  shown  further  that  the  food 
last  swallowed  is  received  into  the  centre  of  the  mass  already  present 
in  the  stomach,  and  does  not  for  some  time  come  into  contact 
with  the  mucous  membrane  and  thus  with  the  gastric  juice.     The 

1  Deut.  Archiv.  f.  Klin.  Med.,  irf94.  ^'i'-  ^cg. 

2  See  Gillespie,  op.  cit.,  p.  157  ;  Aitchison  Robertson,  Edinburgh  Medical  Journal, 
1896,  xli.,  pan  ii.  1010;  A.  E.  Ausun,  Boston  Medical  and  Sut^ioal  Journal,  1899, 
cxl.  325. 


MORBID  GASTRIC  SENSATIONS  421 

central  portion  of  the  contents  can,  therefore,  retain  an  alkaline 
reaction  for  a  considerable  period,  during  which  ptyalin  can  go  on 
acting.  This  justifies  the  conventional  arrangement  of  a  dinner  in 
which  the  starchy  course  (pudding)  comes  after  the  protein  course 
(meat). 

Relation  of  the  Acidity  of  the  Stomach  Contents  to  Morbid 
Gastric  Sensations. 

In  health  digestion  proceeds  quite  unconsciously  and  without  the 
production  of  any  sensation  at  all.  In  morbid  conditions  of  the 
stomach,  however,  digestion  may  be  accompanied  by  sensations 
of  pain,  and  these  seem  to  arise  in  at  least  two  ways :  (i)  from 
disorder  of  the  motor  functions  of  the  stomach  ;  (2)  from  abnormal 
conditions  of  the  mucous  membrane. 

The  former  of  these  we  shall  consider  later.  The  latter  seems  to 
be  of  two  sorts  :  (a)  where  the  mucous  membrane  is  unduly  sensi- 
tive to  the  total  acidity  of  the  contents ;  (b)  where  free  acid  alone 
produces  pain.  The  former  of  these  conditions  seems  to  be  present 
where  actual  lesions  of  the  mucous  membrane  exist — e.g.,  in  ulcer 
and  in  carcinoma  ;  the  latter  is  apparently  more  often  of  the  nature 
of  a  neurosis — a  hyperassthesia  of  the  nerves  of  the  mucous  mem- 
brane, though  it  is  possible  that  in  extreme  degrees  of  such  hyper- 
aesthesia  pain  may  be  produced  even  by  combined  acid.  Where  the 
total  acidity  causes  pain  the  condition  is  likely  to  be  aggravated  by 
foods  rich  in  protein,  such  as  meat,  for  these,  as  we  have  seen,  call 
forth  an  abundance  of  juice,  and  therefore  of  acid.  If,  on  the  other 
hand,  free  acidity  alone  excites  the  sensation,  such  foods  are  likely  to 
be  beneficial,  for  they  delay  the  period  at  which  free  acid  appears,  and 
also  lessen  its  amount.  In  accordance  with  this  explanation,  I  think 
it  will  be  found  that  patients  who  are  suffering  from  ulceration  of  the 
stomach  complain  of  pain  after  meat,  but  can  digest  milk  with  com- 
fort ;  for  milk  not  only  neutralizes  much  acid  by  means  of  its  bases, 
but  in  itself  calls  out  the  secretion  of  a  weak  and  scanty  gastric 
juice.  On  the  other  hand,  one  usually  finds  that  patients  with 
functional  dyspepsia  and  hyperaesthesia  of  the  stomach  suffer  less 
from  meat  than  from  foods  which,  being  poor  in  proteins,  allow 
of  the  early  appearance  of  uncombined  hydrochloric  acid.  These 
considerations  are  of  importance  in  helping  one  to  select  a  suitable 
dietary  for  dyspeptics. 


422  FOOD  AND  DIETETICS 

Movements  of  the  Stomach. 

In  studying  the  movements  of  the  stomach,  one  must  distinguish 
quite  sharply  between  the  cardiac  and  the  pyloric  end  of  the  organ. 
There  is  no  doubt  that  this  distinction  is  not  grasped  as  clearly  as  it 
ought  to  be.  The  two  ends  are  distinct,  both  anatomically  and 
functionally.  The  cardiac  end  secretes  both  pepsin  and  hydro- 
chloric acid,  the  pyloric  end  pepsin  alone.  The  former  has  but 
feeble  motor  power ;  the  movements  of  the  latter  are  frequent  and 
powerful.  This  functional  difference  would  be  found,  I  think,  to 
explain  to  some  extent  the  respective  liability  of  the  two  ends  to 
diflferent  diseases,  but  that  subject  cannot  be  entered  upon  here. 

Nor  is  it  commonly  recognised  that  the  two  portions  of  the 
stomach  are  separated  from  each  other  by  a  thickening  of  the 
muscular  coat — the  transverse  band — which  acts  as  a  kind  of 
'  pre-pyloric  sphincter.'  The  existence  of  this  sphincter  was  long 
ago  pointed  out  by  Retzius.i  It  is  situated  at  a  variable  distance 
from  the  pylorus,  and,  though  it  cannot  always  be  demonstrated 
in  the  cadaver,  it  is  probably  always  present  in  the  living  organ. 
Thanks  to  the  existence  of  this  sphincter,  the  stomach  is  able  to 
'  sort '  its  contents  into  those  which  are  in  a  fit  state  to  be  passed  on 
into  the  intestine,  and  those  which  must  be  kept  back  to  be  further 
acted  upon  by  the  gastric  juice.  The  sorting  is  probably  brought 
about  in  this  way  :  Shortly  after  the  food  enters  the  stomach  feeble 
peristaltic  waves  are  set  up  in  the  cardiac  end,  which  keep  up  a  slow 
revolution  of  the  contents,  sufficient  to  ensure  their  complete  mixing 
with  the  gastric  juice,  but  not  of  sufficient  strength  to  exercise  any 
real  pressure  on  the  food  masses  such  as  might  break  them  up 
mechanically.  These  waves  seem  to  stop  at  the  transverse  band, 
their  point  of  cessation  being  marked  in  the  living  stomach  by 
the  appearance  of  a  sulcus.  They  are  strong  enough  to  squeeze 
the  fluid  part  of  the  contents  past  this  constriction  on  into  the 
pyloric  end,  but  are  not  sufficiently  powerful  to  do  the  same  for 
solid,  undigested  lumps.  In  this  way  the  digested  parts  of  the 
food  are  separated  from  the  rest.  The  movements  of  the  pyloric 
end  are,  as  has  already  been  mentioned,  much  more  active  than 
those  of  the  fundus.  It  is  here  that  the  food  is  mixed  with  the 
gastric  juice,  rubbed  down  into  a  more  or  less  fluid  consistency 
and  expelled  into  the  duodenum.  The  mechanism  by  which  this 
takes  place  is  as  follows  (Cannon) : 

1  Mulhr'i  Archil).,   1S57,  p.  74.     He  describes  the  'transverse  band'  as  the 
•  sphinctei  antri  pylori.' 


MOVEMENTS  OF  THE  STOMACH  423 

Whilst  food  is  present  in  the  stomach  constriction  waves  are  seen 
continually  coursing  over  the  antrum  towards  the  pylorus.  The 
fundus  meanwhile  serves  as  an  active  reservoir  for  the  food,  and 
squeezes  out  its  contents  gradually  into  the  pyloric  portion.  The 
stomach  is  emptied  by  the  formation,  between  the  fundus  and 
antrum,  of  a  tube  along  which  constrictions  pass  at  regular  intervals 
of  fifteen  to  twenty  seconds.  The  contents  of  the  fundus  are  pressed 
into  the  tube,  and  the  tube  and  antrum  slowly  cleared  of  food  by  the 
waves  of  constriction.  The  food  in  the  pyloric  portion  is  first  pushed 
forward  by  the  running  wave,  and  then  by  pressure  of  the  stomach 
wall  is  returned  backwards  through  the  ring  of  constriction,  being 
thus  thoroughly  mixed  with  gastric  juice.  Finally,  when  the  solid 
food  has  been  thoroughly  triturated  by  the  constrictions,  the  pylorus 
opens  and  allows  the  contents  of  the  antrum  to  escape. 

The  activity  of  the  peristaltic  movements  of  the  stomach  seems  to 
depend  in  part  on  the  temperature  of  the  contents,  and  in  part  on 
their  chemical  nature.  Mere  mechanical  contact  seems  to  have  but 
little  stimulating  effect  upon  them.  Hot  food  increases  the 
frequency  and  vigour  of  the  movements,  and  so  does  a  highly  acid 
condition  of  the  contents.  It  may  be  for  this  reason  that  the 
movements  become  more  vigorous  as  digestion  proceeds.  Such 
stimulating  substances  as  mustard,  alcohol  and  carbonic  acid  gas 
seem  to  have  a  similar  effect. 

The  length  of  time  which  elapses  between  the  swallowing  of  food 
and  the  first  opening  of  the  pylorus  is  variable,  depending  chiefly 
upon  the  consistence  of  the  food  and  the  temperature  and  reaction 
of  the  stomach  contents.  Fluids,  unless  they  contain  much  solid 
matter  in  solution,  begin  to  escape  almost  immediately,  water, 
indeed,  whilst  it  is  still  being  swallowed. 

Any  excess  of  fluid  taken  with  a  solid  meal  is  probably  also  passed 
on  almost  at  once,  and  so  cannot  seriously  dilute  the  gastric  juice. 
Solid  food  can  only  escape  after  it  has  been  reduced  to  a  fluid  or 
semi-fluid  consistency,  and  this  must  obviously  depend  to  a  large 
extent  upon  its  physical  characters  and  density. 

Busch,  in  his  observations  upon  a  patient  with  a  duodenal  fistula, 
saw  the  escape  of  food  after  as  short  an  interval  as  fifteen  or  thirty 
minutes.^ 

The  larger  part  of  a  meal,  however,  probably  does  not  pass  out  of 
the  stomach  till  most  of  it  has  been  completely  digested,  and  half  an 
hour  after  that  has  taken  place  the  stomach  may  be  regarded  as 
empty. 

*  Virchow's  Archiv,,  1858,  xiv.  140, 


424  FOOD  AND  DIETETICS 

Warmth  tends  to  accelerate  the  opening  of  the  pylorus,  but  a 
very  acid  condition  of  the  stomach  contents  has  a  contrary  effect. 
Organic  acids  have  perhaps  a  more  powerful  influence  in  this 
direction  than  hydrochloric  acid,  and  may  induce  an  actual  spasm  of 
the  orifice.  A  dose  of  alkali  may  relieve  the  pain  which  such  spasm 
causes.  Hence  it  is  only  towards  the  close  of  digestion,  when  the 
acidity  of  the  stomach  contents  has  been  reduced  by  the  addition  of 
the  neutral  or  slightly  alkaline  secretion  of  the  pyloric  end,  that  the 
conditions  most  favourable  to  the  escape  of  food  come  into  existence. 
It  has  been  found,  also,  that  the  duodenum  exercises  a  controlling 
influence  over  the  pylorus,  distension  of  it  inhibiting  the  opening 
which  would  otherwise  take  place. 

Rate  of  Digestion  of  Different  Foods. 

Seeing  that  food  cannot  be  passed  on  into  the  intestine  until  it 
has  been  brought  into  a  state  of  solution,  it  is  obvious  that  we  have, 
in  the  period  which  elapses  before  the  stomach  is  empty  after  the 
taking  of  any  particular  article  of  diet,  a  criterion  of  its  digestibility 
as  far  as  the  stomach  is  concerned.  In  previous  chapters  the  relative 
digestibility  of  different  foods  has  been  considered  in  detail,  but  it 
may  be  well  at  this  point  to  summarize  our  knowledge  of  the 
subject. 

Most  of  our  information  on  this  matter  has  been  derived  from  the 
experiments  of  Penzoldt  on  healthy  men.^  He  found,  as  might  have 
been  expected,  that  the  amount  and  consistency  of  the  food  have  a 
strong  determining  influence  in  the  rate  of  digestion.  Fluids  escape 
most  rapidly  of  all.  Thus,  7  ounces  (200  c.c.)  of  water  have  entirely 
left  the  stomach  in  one  and  a  half  hours, "^  and  tea,  coffee,  and  alcohoUc 
liquors  in  the  same  time.  Hot  drinks,  contrary  to  what  might  have 
been  expected,  did  not  seem  to  leave  sooner  than  cold,  nor  did  the 
quantity  of  fluid  make  much  difference,  so  that  it  scarcely  matters, 
as  regards  stay  in  the  stomach,  whether  one  takes  3  or  6  ounces  of 
fluid.  On  the  other  hand,  the  presence  of  solid  matter  in  solution 
or  suspension  in  the  fluid  caused  it  to  remain  longer,  but  not  much, 
7  ounces  of  boiled  milk  staying  about  two  hours.  Meat -juices,  and 
water  containing  in  solution  such  substances  as  peptone,  did  not 
remain  any  longer  than  ordinary  water  or  milk.  Aerated  water  was 
found  to  remain  in  the  stomach  for  an  even  shorter  time  than  plain 

^  Deut.  Archiv.f.  Klin.  Med.,  1893,  ^i-  535-  The  experiments  of  Beaumont  are 
of  very  little  value,  owing  to  the  fact  that  they  take  no  account  of  the  amount  of 
food  given. 

"^  The  time  was  always  calculated  from  the  moment  at  which  the  food  had 
begun  to  be  swallowed. 


RATE  OF  DIGESTION  425 

water,  probably  because  the  carbonic  acid  which  it  contains  acceler- 
ates the  stomach  movements. 

As  regards  solids,  digestibility  is  influenced  much  more  by  con- 
sistence than  by  amount.^  An  increase  in  the  quantity  taken  prolongs, 
it  is  true,  the  duration  of  stay  in  the  stomach,  but  not  proportionally. 
Doubling  the  amount  eaten,  for  instance,  does  not  mean  doubling 
the  length  of  time  required  for  digestion.  In  the  case  of  meat,  to 
take  an  example,  an  addition  of  50  grammes  caused  only  an  increase 
of  one  hour  in  the  time  required  for  complete  digestion,  and  in  the 
case  of  biscuits  a  similar  addition  produced  an  extra  delay  in  the 
stomach  of  only  seventy  minutes.  Put  otherwise,  six  times  the 
original  quantity  of  beef  requires  only  three  times  the  original 
amount  of  time  taken  by  digestion;  in  the  case  of  biscuits,  four 
times  the  original  quantity  requires  double  the  time,  while  with 
fluids  the  original  quantity  can  be  increased  five  times  while  only 
doubling  the  original  time. 

The  chemical  composition  of  the  food,  also,  is  of  importance. 
Carbohydrates,  proteins,  and  fats  do  not  leave  the  stomach  at  the 
same  rate.  Carbohydrates  begin  to  leave  the  stomach  within  ten 
minutes  of  their  ingestion ;  they  pass  out  rapidly,  and  at  the  end 
of  two  hours  reach  a  maximum  amount  in  the  small  intestine. 
Fats,  on  the  other  hand,  remain  a  long  time  in  the  stomach.  Their 
discharge  into  the  small  intestine  begins  slowly,  and  continues  at 
about  the  same  rate  as  their  absorption  or  their  passage  onwards 
into  the  large  bowel.  Proteins  remain  an  even  longer  time,  and 
their  rate  of  discharge  is  slower  than  that  of  fats. 

Of  animal  foods,  the  most  rapidly  digested  were  those  of  a  soft 
consistence,  such  as  sweetbread.  The  white  meats,  e.g.,  chicken, 
were  more  digestible  than  dark,  e.g.,  duck,  or  even  the  red  meats, 
but  the  method  of  cooking  had  great  influence  on  the  result.  Fresh 
fish,  in  his  experiments,  was  more  rapidly  digested  than  meat. 

As  regards  vegetable  foods,  the  consistency  and  the  amount  of 
solid  matter  contained  were  again  the  ruling  factors.  Thus,  •  mealy ' 
potatoes  were  more  rapidly  disposed  of  than  '  waxy,'  and  in  puree 
more  easily  than  when  in  pieces.  Fine  bread  and  biscuits  were 
found  to  be  more  digestible  than  coarse  bread,  but  there  was  not 
much  difference  between  crust,  crumb  and  toast,  or  even  between 
new  and  stale  bread,  provided  all  were  equally  well  chewed.  •  Cauli- 
flower was  the  most  rapidly  digested  of  vegetables. 

The  following  table  contains  a  summary  of  these  results  in  greater 
detail,  along  with  the  fuel  value  of  the  quantity  of  each  article 
employed : 

>  See  Lehmann,  •  Ueber  die  Bedeutung  der  Zerkleinerung  und  des  Kochena 
der  Speisen  t  die  Verdauung,'  Arch./.  Hygitnt,  1902,  xliii.  123. 


426 


FOOD  AND  DIETETICS 


TABLE  SHOWING  RATE   OF    DIGESTION   OF   DIFFERENT   FOODS 
AND  THEIR  CALORIE  VALUE.i 


Food. 

400  c.c.  (i4i  ounces)  boiled  milk  .. 

100    grammes    egg,     raw,    poached,   or 

omelette  (  =  about  two  eggs)     .  • 
100  grammes  beef  sausage  (3I  ounces)  . . 
200         ,,         sweetbread  (7  ounces) 
72        „         oysters  (10  of  moderate  size) 
200        „         white  fish  (7  ounces) 
200        „         shell-fish 
150        ,,         asparagus  (5J  ounces) 
100        ,,        white  bread  (3^  ounces  or 

I  i  slices) 28*7 

100  grammes  rusks 

30        „        biscuit  (if  ounces).. 


Pooi. 


230  grammes  chicken  (8J  ounces) 

250 

160 

100 

100 

100 

150 
150 
150   , 


lean  beef  (9  ounces)  . . 

boiled  ham  (6  ounces) 
roast  veal  (3^  ounces) 
beefsteak     , ,       , , 
salted  caviare  (3J  ounces) 
coarse  bread  (5J  ounces)  . . 
boiled  rice       , ,       , , 
boiled  cabbage  (5J  ounces) 


Lbavb  Stomach  in 
Food. 

250  grammes  smoked  tongue  (9  ounces). . 
100  ,,  smoked  beef  (3^  ounces)  .. 
250  „  roast  goose  (9  ounces)  .  • 
2CO  „  salt  herring  (7  ounces)  . . 
150  „  lentil  porridge  (5^  ounces) 
200        ,,         pease  porridge  (7  ounces) . . 

One  may  compare  with  these  observations  those  of  Verhaegen,' 

who  concludes  from  a  large  number  of  experiments  that — 

^  litre  boiled  milk  leaves  the  stomach  in  2J  hours. 
1  „  „  ,.  ..        .    3i     .. 

100  grammes  of  bread  leave  the  stomach  in  3        ,, 
150  ,,  ,.  ..  ..  4         .f 

100  ,,  ,,     and  60  of  meat  leave  the  stomach  in  4  hours. 

An  ordinary  dinner  leaves  the  stomach  in  4  to  5  hours. 


Calories  in  Form  oi 

Total 

j^             "^ 

Culovic 

Protein. 

Carbohydrates. 

~Jat. 

Value. 

574 

788 

i37'6 

273-8 

517 

2-1 

112-5 

166-3 

597 

— 

3720 

431-7 

2296 

— 

0-4 

2300 

177 

10-7 

77 

35-1 

1796 

— 

20-5 

200-1 

1394 

— 

93 

148-7 

123 

12-3 

— 

246 

287 

213-2 

4-6 

2465 

353 

3079 

93 

352-5 

21-4 

150-0 

214 

192-8 

j  TO  4  Hours. 

Calories  in  Form  of 

Total 

Calorie 

Protein. 

Carbohydrates. 

Tat. 

Value. 

1886 

— 

856 

274-2 

215-2 

— 

348 

250-1 

I57'4 

— 

5357 

693-1 

820 

— 

13-9 

95-9 

1403 

— 

764 

216-7 

127-1 

— 

148-8 

2759 

369 

307-5 

6-9 

3513 

i8-5 

467-4 

— 

4859 

i8-5 

49-2 

— 

67-7 

4  TO  5 

Hours. 

Calories  in  Form  of 

Total 

^jL 

Calorie 

Protein. 

Carbohydrates. 

Tat. 

Value. 

2470 

— 

721 

968 

110-7 

— 

139-5 

250-2 

1640 

— 

1060 

122-4 

1549 

12-3 

314-3 

481-5 

153  7 

332-1 

485-8 

1886 

426-4 

— 

6150 

*  Modified  from  Strauss,  Zeit.  f.  Didt.  Therapie,  1900,  iii.  198,  279,  and  based 
on  the  results  of  Penzoldt  (Deut.  Archiv.  f.  Klin.  Med.,  1S93,  li.  535). 

•  'Physiolcgie  et  Pathologic  de  la  Secretion  Gastrique,"  Paris,  1898. 


ANTISEPTIC  ACTION  OF  STOMACH  4^7 

Leube^  divides  foods  into  four  groups,  according  to  the  ease  with 
which  they  are  digested,  the  first  group  containing  those  which  are 
most  digestible : 

1.  Beef-tea,  solution  of  meat  (Leube- Rosenthal),  milk,  soft  or  raw 
eggs,  Albert  biscuits. 

2.  Boiled  calves'  brains,  sweetbread,  boiled  fowl,  pigeon  or  calves, 
feet. 

3.  Scraped  underdone  steak,  potato  puree,  stale  bread. 

4.  Roast  chicken  or  pigeon,  roast  veal,  cold  roast  beef  (underdone), 
white  fish,  macaroni,  rice,  chopped  spinach. 

A  study  of  all  these  results  will  enable  one  to  select  the  most 
suitable  foods  for  persons  of  weak  digestion. 

3.  Antiseptic  Action  of  the  Gastric  Juice.  —  Another  function 
which  the  stomach  serves  is  that  of  partially  sterilizing  the  food 
by  the  antiseptic  action  of  the  hydrochloric  acid  of  the  gastric 
juice.  This  action,  however,  is  not  a  powerful  one,  and  some 
organisms,  such  as  those  that  form  acids,  seem  to  escape  it 
altogether,  and  there  is  reason  to  believe  that  the  same  is  true  of 
some,  at  least,  of  the  commoner  pathogenic  organisms,  notably  the 
tubercle  bacillus. 

The. sterilizing  power  of  the  stomach  must  vary  greatly  according 
to  the  period  of  digestion  and  the  nature  of  the  food.  It  probably 
reaches  its  maximum  towards  the  later  periods  of  digestion,  when 
hydrochloric  acid  is  present  in  the  free  state,  whilst  it  is  much  less, 
or  even  absent  altogether,  in  the  earlier  stages,  when  all  the  hydro- 
chloric acid  is  in  a  combined  form.  Food  rich  in  protein,  by  fixing 
the  hydrochloric  acid,  must  greatly  lessen  the  germicidal  power  of 
the  gastric  juice.  Over  the  growth  of  organisms  in  the  intestine  the 
stomach  seems  powerless  to  exert  any  control.  Even  in  cases  in 
which  the  secretion  of  hydrochloric  acid  is  entirely  arrested,  or  in 
which  the  stomach  has  been  completely  removed,  no  increase  in  the 
amount  of  intestinal  putrefaction  was  found  to  occur. ^ 

4.  The  Temperature  of  Foods  and  Drinks.  ^ — One  of  the  minor 
functions  of  the  stomach  is  that  of  regulating  the  temperature  of 
the  food.  It  stands  in  this  matter  as  a  protector  of  the  intestine, 
which  appears  to  be  more  injuriously  affected  by  extremes  ot 
temperature  than  the  stomach  itself. 

The  ideal  temperature  for  food  is  probably  that  of  the  body  itself. 

>  Zeit.f  Klin.  Med.,  1883,  vi.  189. 

»  See  Schlatter,  Lancet,  1898,  i.  141,  and  Filippi,  Deut.  Mei.  Wochensch.,  1894, 
XX.  780. 

»  See  Spath,  Archiv.  /.  Hygiene,  1886,  iv,  68,  and  Uffelmann,  Wtentr  Kltntk, 
1887,  xiii.,  Heft  9, 


428  FOOD  AND  DIETETICS 

Cold  food  is  difficult  to  digest,  for  it  does  not  excite  the  stomach 
sufficiently,  nor  does  it  possess  the  stimulating  properties  of  a  hot 
meal.  It  has  been  observed  that  there  is  a  special  craving  for 
alcoholic  stimulants  on  the  part  of  those  who  are  unable  to  get  hot 
meals. 

Extremes  of  temperature  in  foods  should  be  avoided  as  tending  to 
produce  local  injury  to  the  stomach;  from  45°  to  130°  F.  are  prob- 
ably the  limits  of  safety. 

Drinks  at  a  temperature  of  122°  F.  are  sufficient  to  warm  the 
body,  and  a  temperature  of  45°  F.  is  sufficient  to  cool  it.  Wunder- 
lich^  found  that  hot  punch  at  122°  F.  raised  the  temperature  of  the 
body  by  0'i°  to  •03°  C.  for  a  period  of  thirty  to  sixty  minutes,  while 
half  a  litre  of  water  at  the  same  degree  of  heat  caused  an  accelera- 
tion of  the  pulse  by  nearly  20  beats  per  minute  very  shortly  after  it 
had  been  swallowed. 

On  the  other  hand,  three  tumblerfuls  of  water  at  a  temperature  of 
45°  F.  produced  a  lowering  of  the  axillary  temperature  from  98-4°  F. 
to  977°  F.,  while  the  pulse-rate  fell  from  70  to  61  per  minute. 

Violent  alternations  in  the  temperature  of  foods  seem  to  cause 
fissuring  of  the  enamel  of  the  teeth.  Uffelmann,  for  instance,  placed 
recently-extracted  teeth  in  water  first  at  65°  C,  and  then  directly 
afterwards  at  6°  C,  and  in  nine  out  of  eleven  cases  he  produced 
some  degree  of  splitting  of  the  enamel. 

The  local  effects  of  extremes  of  temperature  in  the  stomach  are 
very  much  the  same  whether  the  extreme  be  one  of  heat  or  of  cold. 
In  each  case  there  is  a  danger  of  exciting  gastric  catarrh.  Very  hot 
foods  seem  to  be  specially  dangerous  in  stomach-bleedings,  e.g., 
ulcer ;  and  there  are  some  who  say  that  the  special  liability  of  cooks 
to  suffer  from  gastric  ulcer  is  to  be  attributed  to  their  constantly 
tasting  very  hot  foods.  On  the  other  hand,  very  warm  fluids  may 
relieve  pain  in  the  stomach  by  abolishing  pyloric  spasm. 

The  temperature  most  suited  for  drinks  intended  to  quench  thirst 
is  one  of  from  50°  to  70°  F.  Ices  should  be  avoided,  as  they  may 
cause  dyspepsia,  cardialgia,  and  even  acute  dilatation  of  the  stomach, 
although  small  quantities  of  ice  undoubtedly  tend  to  allay  gastric 
irritability.  It  must  also  be  remembered  that  the  drinking  of  very 
cold  water  when  one  is  heated  may  bring  about  a  reflex  congestion 
of  the  lungs. 

5.  Absorptive  Power  of  the  Stomach. — The  absorptive  power 
of  the  stomach  is  surprisingly  small.     In  this  also  one  may  see 

*  Quoted  by  Uffelmann. 


INTESTINAL  DIGESTION  429 

a  provision  for  the  protection  of  the  body,  for  it  allows  of  the 
neutralization  or  rejection  of  injurious  substances  before  they  have 
time  to  enter  the  blood.  Alcohol,  curiously  enough,  is  of  all 
substances  that  which  the  stomach  absorbs  most  readily.  This 
explains  to  some  extent  the  rapid  stimulating  action  of  alcohol. 
Peptone,  sugars  and  salts,  are  also  absorbed  by  the  stomach  to 
some  extent.  The  stronger  the  alcohol,  or  the  more  concentrated 
the  solution  of  these  substances,  the  greater  is  the  degree  of  absorp- 
tion. 

There  is  reason  to  believe  that  the  process  of  absorption  by  the 
stomach  is  much  more  of  the  nature  of  a  mere  physical  osmosis  than 
is  the  case  in  the  intestine,  and  the  process  is  accompanied  by  the 
pouring  out  of  a  good  deal  of  secretion.  It  is  in  this  way,  perhaps, 
that  a  mixture  of  alcohol  and  sugar,  such  as  is  found  in  sweet  wines 
and  some  malt  liquors,  may  cause  '  acidity.'  The  practical  bearings 
of  absorption  in  the  stomach  will  be  more  fully  dealt  with,  however, 
when  we  come  to  consider  the  dietetic  treatment  of  gastric  dilatation. 

Digestion  and  Absorption  in  the  Intestine. 

When  the  food  has  passed  through  the  pylorus,  it  enters  the 
duodenum  and  encounters  the  secretion  of  the  pancreas.  The 
anatomical  disposition  of  the  duodenum  seems  specially  designed  to 
favour  complete  mixing  of  the  chyme  with  the  pancreatic  juice,  for 
the  duodenal  loop  forms  a  kind  of  U-tube,  in  which  some  delay  of 
the  contents  may  be  expected  to  take  place.  The  degree  of  disten- 
sion of  this  loop  seems  to  have  some  influence,  too,  over  the  opening 
of  the  pylorus,  so  that  as  long  as  the  duodenum  is  full  no  further 
escape  of  food  from  the  stomach  takes  place. 

The  chief  stimulant  of  the  pancreatic  secretion  is  the  hydrochloric 
acid,  which  reaches  it  from  the  stomach ;  the  psychical  factor,  though 
active,  is  not  nearly  so  potent  as  in  the  case  of  gastric  secretion. 
The  chemical  constituents  of  the  food  also  have  an  influence,  just 
as  they  have  in  the  case  of  the  stomach,  fat  especially  calling  forth 
an  abundant  secretion.  As  the  pancreatic  juice  is  the  chief  agent 
concerned  in  the  digestion  of  fat,  we  see  in  this  again  a  wonderful 
adaptation  of  means  to  ends.  Starch,  on  the  other  hand,  has  no 
great  effect  beyond  that  of  producing  a  slight  increase  in  the  amount 
of  the  sugar-forming  ferment. 

Of  the  disorders  of  pancreatic  digestion  we  know  but  little,  though 
they  are  probably  of  less  importance  than  those  of  the  stomach,  for 
the  reserve  power  of  the  pancreas  seems  to  be  so  great  that  it  is  quite 


430  FOOD  AND  DIETETICS 

equal  to  digesting  the  whole  of  the  food  itself  should  the  stomach  be 
unable  to  perform  its  share  in  the  process.  The  importance  of  this 
for  dyspeptics  is  very  great. 

As  the  food  passes  along  the  intestine  absorption  of  its  ingredients 
takes  place,  and  the  degree  to  which  this  occurs  in  different  foods  has 
already  been  fully  considered  (p.  lo.) 

The  influence  of  each  constituent  of  the  food  on  the  absorption  of 
others  is  probably  of  considerable  importance,  though  not  much  is 
known  about  it.  The  addition  of  starch  to  protein,  for  example, 
diminishes  the  absorption  of  the  latter,  whilst  fat  starvation  tends  to 
lessen  the  absorption  of  phosphoric  acid.^  On  the  other  hand,  if  fat 
is  not  being  well  absorbed,  as,  for  example,  in  cases  where  the  bile 
cannot  enter  the  duodenum,  the  destruction  of  proteins  by  putre- 
faction is  greatly  increased,  owing  to  the  unabsorbed  fat  enclosing 
the  particles  of  protein  and  interfering  with  their  proper  digestion. 
This  furnishes  an  additional  reason  for  interdicting  fat  in  jaundice. 
The  increase  of  intestinal  putrefaction  brought  about  in  this  indirect 
way  no  doubt  led  to  the  erroneous  idea  that  bile  is  an  antiseptic. 
Seeing  that  the  influence  of  the  carbohydrates  is  rather  to  retard  the 
putrefaction  of  proteins,  it  is  obvious  that  fats  cannot  replace  the 
former  as  far  as  the  intestine  is  concerned.^ 

The  role  of  bacteria  in  intestinal  digestion  has  sometimes  been 
minimized,  at  others  exaggerated.  There  is  no  doubt  that  they  are 
not  indispensable  to  digestion.  On  the  other  hand,  they  play  a 
useful  part  in  restraining  putrefaction.  The  only  bacteria  which 
flourish  in  the  small  intestine  are  those  which  are  capable  of  forming 
acids  (e.g.,  acetic,  lactic,  and  succinic)  out  of  carbohydrates.  The 
acids  so  produced  tend  constantly  to  be  neutralized  by  the  alkaline 
secretion  of  the  intestinal  mucous  membrane,  but  in  the  struggle 
which  thus  takes  place  the  acids  always  maintain  the  upper  hand, 
and  consequently  the  contents  of  the  small  intestine  have  an  acid 
reaction  throughout.  Thanks  to  this  slight  degree  of  acidity,  the 
growth  of  putrefactive  organisms  is  restrained,  and  the  destruction 
of  proteins  especially  prevented.  Hence,  if  one  wishes  to  diminish 
intestinal  putrefaction,  the  diet  must  contain  plenty  of  carbohydrates, 
for  it  is  only  out  of  these  that  acids  can  be  produced,  and  but  little 
protein.8    This  explains  the  very  foetid  nature  of  the  stools  passed 

^  Journal  of  Experimental  Medicine,  1898,  iii.  293. 

*  See  Laas,  '  Ueber  den  Einfluss  der  Fette  auf  die  Ausnutzung  der  Eiweisstoffe,' 
Zeit.  /.  Physiolog.  Chem.,  1894,  xx.  233. 

^  See  Backman,  '  Ein  Beitrag  zur  Kenntniss  der  Darmfaulniss  bei  Verschie- 
denen  Diatformen  unter  physiologischen  Verhaltnissen,'  Zeit.  /.  Klin.  Med.,  1902, 
xliv.  458. 


FAiCES  431 

by  patients  who  are  being  fed  exclusively  on  lean  meat.  It  may  be 
well  also  to  remind  the  reader  again  at  this  point  of  the  value  of  milk 
as  an  intestinal  antiseptic  (see  p.  126). 

It  is  important  to  remember  that  the  contents  of  the  small 
intestine  remain  fluid  throughout  its  entire  length.  Even  at  the 
lower  end  of  the  ileum  the  amount  of  solid  matter  is  only  5  to 
10  per  cent.  The  advantages  of  a  fluid  diet  in  intestinal  ulceration, 
therefore,  can  scarcely  be  due  to  any  less  degree  of  mechanical 
irritation  on  the  part  of  fluid  food. 

In  the  large  intestine  the  contents  of  the  bowel  are  brought  to  a 
solid  form,  mainly  by  the  absorption  of  water.  The  absorptive 
power  of  the  large  intestine  for  the  nutritive  constituents  of  the  food 
will  be  considered  in  another  chapter. 

The  investigation  of  Prausnitz^  has  shown  that  the  faeces  are  to 
be  regarded  as  chiefly  composed  of  the  remains  of  the  digestive 
juices,  and  that  their  composition  is  very  uniform,  the  chief 
ingredients  (in  the  dried  form)  being 

Nitrogen        8  to  9  per  cent. 

Ether  extract  ..         ..     12  to  18      ,, 

Mineral  matter        ..         ..     121015      .• 

The  faeces  of  a  mixed  diet  always  contain  muscle  fibres,  but  starch 
is  completely  absorbed  unless  pulses  or  green  vegetables  are  largely 
eaten. 

If  the  diet  is  of  sucH  a  nature  that  much  cellulose  and  some  starch 
are  excreted,  the  percentage  of  nitrogen  falls.  If,  on  the  contrary, 
the .  absorption  of  nitrogen  is  deficient,  the  percentage  of  that 
ingredient  rises.  Other  things  being  equal,  therefore,  a  low  per- 
centage of  nitrogen  in  the  faeces  indicates  bad  general  absorption 
of  the  food,  while  a  high  proportion  of  nitrogen  has  a  contrary 
significance. 

The  bulky  faeces  of  a  vegetable  diet  are  largely  due  to  the 
presence  of  an  excess  of  moisture,  which  has  been  poured  out  by  the 
walls  of  the  bowel  in  the  attempt  to  neutralize  organic  acids 
produced  by  fermentation. 

In  the  large  intestine,  the  putrefactive  bacteria  are  able  to  flourish, 
for  the  absorption  of  carbohydrates  higher  up  renders  the  further 
production  of  acids  which  restrain  putrefaction  impossible. 

The  following  summary  of  the  digestion  of  a  mixed  meal  may  serve 
to  gather  up  a  number  of  the  scattered  facts  which  have  been 
mentioned  in  the  preceding  paragraphs  : 

The  complex  sensation  called  '  hunger '  impels  one  to  seek  food. 
*  Zeit.  j.  Biologic,  1897,  xxxv.  287. 


432  FOOD  AND  DIETETICS 

The  sight  and  smell  of  the  food  awakens  the  sensation  ol  '  appetite,' 
and  with  it  there  begins  a  flow  of  digestive  juices,  most  marked  in 
the  case  of  the  stomach.  The  soup,  which  usually  forms  the  first 
course,  by  virtue  of  its  warmth  and  of  the  gelatin  and  extractives 
which  it  contains,  accelerates  and  increases  the  secretion  of  the 
gastric  juice.  The  solid  part  of  the  food  is  reduced  to  a  pulp  in  the 
mouth,  and,  unless  acid  substances  are  mixed  with  it,  part  of  its 
starch  is  changed  into  sugar.  Arrived  in  the  stomach,  it  encounters 
the  '  psychical '  juice  already  secreted,  the  acid  of  which  is  imme- 
diately laid  hold  of  by  the  proteins  of  the  food.  In  this  way  the 
acidity  of  the  stomach  contents  is  kept  down,  and  the  action  of  the 
saliva  upon  the  starch  is  allowed  to  continue.  As  the  solids  become 
dissolved  by  the  '  psychical '  juice,  their  chemical  constituents  are 
set  free,  and  themselves  begin  to  excite  a  specific  secretion  specially 
fitted  for  their  own  digestion. 

Meanwhile,  the  acidity  of  the  contents  goes  on  increasing,  and 
soon  brings  to  an  end  any  further  action  of  the  saliva  upon  starch, 
and  kills  or  paralyzes  many  of  the  organisms  swallowed  with  the 
food,  while  at  the  same  time  the  peristaltic  movements  of  the 
stomach  are  excited.  Under  the  influence  of  these  the  gastric  juice 
and  the  food  are  intimately  mixed,  and  the  temperature  of  the  mass 
gradually  adjusted  to  that  of  the  body.  As  solution  proceeds,  the 
semi-fluid  part  of  the  contents  along  with  any  excess  of  fluid  which 
has  been  swallowed  finds  its  way  into  the  pyloric  end  of  the  stomach, 
and  by  the  systolic  contractions  of  the  latter  is  propelled  into  the 
duodenum.  This  process  continues  for  about  four  or  five  hours,  by 
the  end  of  which  time  the  stomach  is  again  empty.  During  all  this 
time  the  absorption  of  alcohol  and  small  quantrties  of  peptone,  sugar, 
and  salts  has  been  taking  place. 

Arrived  in  the  duodenum,  the  food  encounters  the  secretion  of 
the  pancreas  already  called  out  by  psychical  influences,  and  now 
increased  by  the  stimulus  of  the  acidity  of  the  stomach  contents  and 
by  the  specific  chemical  action  of  the  constituents  of  the  chyme, 
especially  by  that  of  fat.  Here  digestion  is  completed,  and  as  the 
food  sweeps  along  the  small  intestine  its  constitueats  are  rapidly 
absorbed  into  the  blood,  or  chyle.  During  this  time  certain  bacteria, 
which  have  escaped  the  action  of  the  gastric  juice,  are  busy  breaking 
up  any  carbohydrates  which  may  be  present,  producing  from  them 
organic  acids,  which  restrain  the  putrefaction  of  the  protein  con- 
stituents of  the  food  which  would  otherwise  be  apt  to  occur.  The 
fluid  poured  out  by  the  glands  of  the  small  intestine  in  the  attempt 
to  neutralize  these  acids  more  than  makes  up  for  any  absorption  of 


INFLUENCE  OF  EXERCISE  AND  REST  433 

water,  and  causes  the  contents  of  the  ileum  to  remain  fluid  until  the 
large  intestine  is  reached.  Beyond  this  point  the  production  of  acids 
ceases,  and  the  rapid  absorption  of  water  causes  the  contents  to 
assume  a  solid  form,  while  putrefactive  bacteria  are  able  to  grow 
unchecked,  save  by  the  products  of  their  own  activity.  Finally  the 
residue  is  expelled  in  the  form  of  fasces,  usually  about  twenty-four 
hours  after  the  food  was  first  swallowed. 

The  respective  influence  of  exercise  and  rest  on  the  processes 
of  digestion  is  disputed.  Beaumont,  from  his  observations  on 
St.  Martin,  came  to  the  conclusion  that  gentle  exercise  aided 
digestion,  but  the  experiments  of  Fleischer^  gave  a  contrary  result. 
The  whole  question  is  probably  one  of  blood-supply.  Gentle 
exercise,  by  increasing  the  rapidity  of  the  circulation,  may  aid  the 
secretion  of  digestive  juices  and  stimulate  the  movements  of  the 
stomach.  Severe  exercise,  on  the  other  hand,  by  diverting  much 
blood  and  nervous  energy  to  the  muscles,  may  be  expected  to  have 
an  adverse  effect.  Sleep  is  only  useful  as  an  aid  to  digestion  in  the 
case  of  invalids  and  aged  persons,  but  even  in  them  it  may  be 
injurious,  probably  on  account  of  the  depression  of  the  circulation 
by  which  it  is  accompanied. 

On  the  whole  one  can  agree  with  King  Chambers,  that  the  best 
employment  after  a  heavy  meal  is  *  frivolous  conversation,'  which 
keeps  the  heart  active  without  making  great  demands  upon  the 
brain. 

*  Berlin.  Kim.  Wochtnsch.,  1882,  xix.  97. 


38 


[434  1 


CHAPTER  XXIV 

THE  PRINCIPLES  OF  FEEDING  IN  INFANCY  AND 
CHILDHOOD :   HUMAN  MILK 

I.  Physiological  Requirements  in  the  Diet  of  Infancy. 

A  healthy  infant  spends  most  of  its  time  in  sleeping  and  growing. 
Its  muscular  efforts  are  confined  to  a  little  sucking,  more  or  less 
crying,  and  some  kicking.  Hence  it  follows  that  the  diet  of  an 
infant  should  contain  relatively  more  of  the  tissue-builders  (proteins 
and  mineral  matters),  and  relatively  less  of  the  energy-producers 
(carbohydrates),  than  one  finds  in  the  food  of  the  adult.  Like  all 
small  animals,  too,  the  infant  has  a  large  extent  of  surface  in  pro- 
portion to  its  bulk  ;  thus  it  tends  to  lose  heat  rapidly,  and  requires 
an  abundant  supply  of  the  chief  body  fuel — fat.  If  these  different 
ingredients  be  not  supplied  in  due  proportion,  disorder  of  health 
inevitably  follows.  If  the  tissue-builders  be  not  sufficiently  repre- 
sented, the  muscles,  blood,  and  bones  are  not  properly  formed,  and 
the  child  becomes  flabby,  pale,  and  rickety.  On  the  other  hand,  if 
the  supply  of  protein  be  in  excess  of  the  child's  digestive  and  assimi- 
lative powers,  it  suffers  from  disorder  of  the  stomach  and  bowels. 
If  it  be  an  infant,  curdy  stools  will  be  passed,  and  there  will  be 
a  tendency  to  diarrhoea.  Older  children  will  suffer  from  indigestion, 
irritability,  and  restlessness.  A  sufficient  supply  of  fat  is  of  even 
greater  importance.  Indeed,  it  may  be  said  that  abundance  of  fat 
should  be  the  main  characteristic  of  the  diet  of  infancy,  just  as 
abundance  of  carbohydrates  is  the  chief  feature  of  the  diet  of  adult 
and  laborious  life.  The  fat  serves  as  fuel.  Without  it  the  child 
has  difficulty  in  maintaining  the  proper  temperature  of  its  body,  and 
is  liable  to  catarrhs  of  the  lung  or  bowel.  In  addition  to  this  great 
use,  fat  seems,  during  the  period  of  rapid  growth,  to  be  itself  a 
tissue-producer.  The  infant  is  laying  down  a  considerable  amount 
of  tissue  rich  in  fat  in  the  marrow  of  its  bones  and  in  its  nervous 
apparatus,  and  it  may  well  be  that  the  fat  of  the  diet  aids  in  the 


REQUIREMENTS  OF  INFANCY  435 

production  of  such  tissues.  Of  this,  at  any  rate,  there  can  be 
no  doubt,  that  a  child  whose  diet  is  deficient  in  fat  rapidly  loses 
vigour  and  is  extremely  prone  to  suffer  from  rickets.  The  frequent 
connection  between  rickets  and  deficiency  of  fat  in  the  food  is  an 
undeniable  clinical  fact,  of  which,  however,  it  is  difficult  to  give  a 
satisfactory  explanation.  Experiments  have  been  made^  in  which 
young  animals  were  fed  on  separated  milk  practically  free  from  fat ; 
but  although  the  absorption  of  phosphoric  acid  by  them  was  found 
for  some  reason  or  another  to  be  much  interfered  with,  yet  they  did 
not  suffer  from  rickets. 

Important  though  an  abundant  supply  of  fat  is,  one  must  take  care 
not  to  give  it  in  excess,  for  under  these  circumstances  it  is  a  frequent 
cause  of  vomiting  and  diarrhoea.  A  milk  which  contains  more  than 
6^  per  cent,  of  fat  may  always  be  expected  to  produce  these  results. 

Carbohydrates  are,  as  we  have  seen,  not  of  so  much  importance  in 
the  dietary  of  infancy  as  in  that  of  older  children  or  the  adult. 
They  are  important,  however,  not  only  as  making  provision  for 
what  muscular  effort  the  child  does  display,  but  also  in  their 
capacity  as  protein-sparers  (p.  22).  If  there  be  a  due  supply  of 
sugar  in  the  diet,  it  is  reasonable  to  suppose  that  less  protein  will 
suffice.  The  carbohydrates,  however,  are  the  ingredient  of  the  diet 
which  is  least  likely  to  be  represented  in  too  small  amount.  On  the 
contrary,  there  is  a  much  greater  danger  of  supplying  them  in  excess, 
or  of  making  them  a  substitute  for  fat.  An  infant  which  is  the 
victim  of  such  an  error  may  be  plump  enough,  but  its  muscles 
are  flabby,  its  skin  pale,  and  its  bones  often  rickety.  It  is  the 
false  appearance  of  good  nutrition  which  such  infants  often  possess 
that  is  apt  to  deceive  the  uninitiated,  and  such  children  have  been 
known  to  receive  prizes  at  baby- shows,  when  all  the  time  they  were 
undoubtedly  the  subjects  of  rickets.  It  must  be  remembered,  too, 
that  carbohydrates,  especially  when  given  in  excess  and  in  unsuit- 
able forms,  such  as  starch  or  cane-sugar,  are  very  prone  to  undergo 
fermentation  in  the  stomach  and  intestine  of  the  infant,  whereby 
acids  are  produced  and  griping  and  diarrhoea  result. 

The  mineral  ingredients  of  the  food  in  infancy  are  equal  in 
importance  to  the  proteins.  Like  these,  they  are  concerned  in 
building  up  the  child's  body,  and  deficiency  of  them  will  produce 
much  the  same  symptoms  as  deficiency  of  proteins.  Salts  of  lime, 
potash,  and  phosphoric  acid  are  specially  important.  Phosphate  of 
lime  is  wanted  for  the  bones,  and  phosphate  of  potash  for  the 
muscles  and  blood.  It  must  net  be  supposed  that  it  is  a  matter 
*  Journal  of  Experimental  Medicine,  1898,  iii.  293. 


436  FOOD  AND  DIETETICS 

of  indifference  in  what  form  these  are  suppHed.  It  would  seem 
that  these  salts  are  of  much  greater  use  when  they  enter  the  body 
in  combination  with  organic  matter  than  they  are  in  a  free  mineral 
form.  Milk,  and  especially  human  milk,  is  peculiarly  rich  in  organic 
combinations  of  these  salts,  and  for  this  reason  lime-water  or  chemical 
preparations  of  salts  can  be  no  proper  substitute  for  it.  On  the  other 
hand,  there  is  no  reason  to  believe  that  the  presence  of  an  excessive 
quantity  of  mineral  matter  in  the  food  of  an  infant  does  any  harm  ; 
the  child  simply  does  not  absorb  or  assimilate  more  of  each  com 
pound  than  it  requires  for  building  or  other  purposes. 

The  importance  of  water  to  the  infant  will  be  evident  when  one 
recollects  that  more  than  three-fourths  of  the  whole  body  consists  of 
it,  and  that  it  constitutes  about  four-fifths  of  milk,  which  is  the 
natural  diet  of  infancy.  Water  has  also  local  uses  in  the  stomach 
and  bowels,  promoting  as  it  does  the  processes  of  absorption  and 
secretion.  One  is  too  apt  to  forget  that  an  infant  may  suffer  from 
thirst  as  well  as  from  hunger,  and  that  water  will  allay  the  former 
better  than  milk.  The  effect  of  a  drink  of  cold  water  is  certainly 
always  worth  trying  if  a  child  is  suffering  from  evident  but  un- 
explained discomfort. 

2.  Human  Milk:  its  Composition  and  Variations. 

We  have  spoken  on  the  one  hand  of  the  importance  of  a  due 
supply  of  each  nutritive  ingredient  in  the  diet  of  the  infant,  and 
on  the  other  of  the  danger  to  health  which  results  if  any  one  of 
them  be  present  in  excess.  One  naturally  turns  to  human  milk, 
the  natural  food  of  infants,  for  guidance  as  to  the  proper  quantity 
of  each  ingredient  to  be  supplied,  and  for  this  reason  the  study  of 
its  exact  chemical  composition  is  of  the  first  importance.  On  sur- 
veying the  records  of  the  chemical  analyses^  of  human  milk  which 
have  been  made,  one  is  struck  both  by  the  enormous  amount  of 
work  which  has  been  done  on  the  subject,  and  at  the  same  time  by 
the  discrepancies  in  the  results  of  different  observers.  These  dis- 
crepancies are  to  be  explained  partly  by  technical  difficulties  in  milk 
analysis,  and  partly  by  the  fact  that  the  milk  of  one  woman  may 
differ  not  only  from  that  of  another,  but  may  also  show  variations 
from  day  to  day  and  at  different  periods  of  nursing.^ 

^  For  a  review  of  analyses  of  human  milk,  see  Blauberg,  '  Experimentelle  und 
Kritische  Studien  iiber  Sauglingsfaces, '  Berlin,  1897,  and  Hauser,  For/scAr.  der 
Med.,  1S97,  XV.  929. 

2  Konrad  Gregor  (Volkmann's  Samml.,  1901,  M.  88,  N.F.,  No.  302)  finds  that  the 
fat  is  a  particularly  variable  ingredient  of  human  milk,  the  amount  of  it  fluctuating 
from  day  to  day  and  from  hour  to  hour.  This  shows  the  futility  of  basing  con- 
clusions upon  the  result  of  the  examination  of  a  single  sample  of  milk. 


COMPOSITION  OF  HUMAN  MILK 


437 


Milk-sugar     ..         .. 

6'26  per  cent. 

Mineral  matter        .. 

0-27        „ 

Citric  acid 

0-05        „ 

Unknown  extractives 

o'gi        >• 

Reaction 

Alkaline. 

The  following!  represents  the  results  of  analyses  of  human  milk, 
taken  about  the  middle  of  the  second  week  of  nursing  : 

Specific  gravity         ,.  1032 

Water 87-75  per  cent. 

Solids  ..  ,,         ..  12 '25         ,, 

Protein  ..         ..  i'62         ,, 

Fat 3-14 

A  healthy  woman  produces  700  to  2,000  grammes  (i^  to  4  pints) 
of  such  milk  daily,  although  the  former  figure  would  be  much  nearer 
the  average  than  the  latter. 

I  should  like  to  direct  special  attention  to  two  points  in  the 
above  analysis :  First,  to  the  small  amount  of  protein  which  human 
milk  contains,  and,  secondly,  to  the  presence  of  a  considerable 
proportion  of  '  extractive '  matters.  These  are  admittedly  of 
unknown  nature,  but  they  contain  nitrogen.^  The  earlier  analysts 
classed  them  amongst  the  proteins,  and  hence  overstated  the 
amount  of  the  latter  which  human  milk  contains.  Furthermore, 
the  above  analysis  must  only  be  taken  as  representing  the  average 
composition  of  human  milk.  Considerable  variations  are  met 
with,  the  causes  of  which  may  be  considered  under  the  following 
heads : 

I.  Variations  dependent  on  the  Period  of  Suckling. — One  might 
naturally  expect  that  an  infant  a  few  days  old  would  not  require 
the  different  ingredients  of  milk  in  exactly  the  same  relative  pro- 
portions as  one  of  some  weeks,  and  chemical  analysis  of  milk  at 
different  periods  of  lactation  verifies  the  expectation. 

The  milk  secreted  during  the  first  two  or  three  days  after  the 
birth  of  the  child  is  called  colostrum,  and  has  some  peculiar 
characters.  It  is  more  watery-looking  than  ordinary  milk,  and 
contains  a  special  form  of  protein,  which  causes  it  to  cJot  on 
boiling  for  the  first  day  or  two.  The  actual  amount  of  protein 
which  it  contains  is  greater  than  in  ordinary  milk,  though  the 
exact  figures  given  by  different  analysts  vary  on  the  point,  some 
placing  the  amount  of  protein  as  high  as  8  per  cent.  The  following 
table  contains  the  average  of  a  number  of  samples  of  colostrum 
analyzed  by  Woodward  :^ 


*  Analysis  by  Camerer  and  Soldner,  Zeit. /.  Biolog.,  1896,  xxxiii.  535. 

*  According  to  Kjetschel  (Abst.  in  Maly's  Jahrbuch  Thier-Chemie,  1906,  xxxvi. 
259),  about  80  per  cent,  of  the  non-protein  nitrogen  of  human  milk  is  contained 
in  urea,  the  rest  being  present  in  peptides  and  peptoids. 

*  Journal  0/  Experimental  Medicine,  1897,  ii.  217. 


438 


FOOD  AND  DIETETICS 


Specific  gravity  ..     1024101034 

(variations  due  to  differences  in  the 
amount  of  fat) 

Water 875  per  cent. 


Protein 
Fat 

Sugar    . . 
Mineral  matter 


19  per  cent 

4'o 

65         .. 

0-2 


Colostrum  may  contain  a  number  of  peculiar  microscopic  cells 
called  colostrum  corpuscles,  the  number  of  which  is  very  variable. 
As  they  consist  of  protein;  they  must  be  of  some  nutritive  value  to 
the  child.  One  of  the  uses  of  colostrum  appears  to  be  as  a  laxative, 
causing  the  expulsion  from  the  intestine  of  the  child  of  a  quantity  of 
waste  matter  with  which  it  comes  into  the  world. 

After  the  third  day  the  ordinary  milk  begins  to  be  produced,  and 
the  changes  which  it  undergoes  in  composition  from  this  period 
onwards  are  exhibited  in  the  following  table : 

INFLUENCE  OF  PERIOD  OF  LACTATION  ON  COMPOSITION  OF 
HUMAN  MILK.i 


Increast  in 

Period. 

Total  N. 

Protein. 

Fat. 

Sugar. 

Ash. 

Child's  Weight 
per  Day. 

5th  day 

033 

20 

28 

54 

034) 

35  to  40 
grammes 

8th  to    nth  day 
20th  ,,    40th    „ 

027 
020 

16 

31 
3-8 

62 
6-4 

0-27  1 
022  ; 

70th    ,,   I20th     „ 

017 

10 

29 

6-7 

020 

22       ,, 

170th  and  after 

014 

08 

26 

68 

019 

18      .. 

A  study  of  it  will  show  that  on  the  whole  the  building  material 
(protein  and  mineral  matter)  tends  to  become  less  in  amount  as 
lactation  proceeds,  the  sugar  rises  rapidly  up  to  the  end  of  the 
second  week,  and  after  that  more  slowly,  while  the  fat,  after  reaching 
a  maximum  about  the  second  month,  tends  to  fall  off  again  in  the 
later  periods. 

A  Uttle  consideration  will  show  that  these  variations  are  very 
much  what  one  would  expect  from  the  physiological  requirements  of 
the  infant  at  different  ages.  During  the  first  few  weeks  of  life  the 
child  grows  much  faster  than  subsequently.  The  last  column  of  the 
table  shows  that  in  the  first  month  from  35  to  40  grammes  are  added 
to  the  weight  each  day,  while  by  the  time  the  sixth  month  is  reached 
the  daily  increase  in  weight  has  fallen  to  i8  grammes.  Obviously, 
then,  the  infant  will  require  relatively  more  building  material  at  the 
former  period  than  at  the  latter.  The  gradual  increase  in  the 
proportion  of  carbohydrate  is  also  just  what  one  would  expect  in 
view  of  the  daily  increasing  muscular  activity  of  the  child. 

A  general  consideration  of  the  table  clearly  shows  that  the  milk  of 

»  From  analyses  by  Camerer  and  Soldner,  Zeit.  f.  Biolog.,  1896,  xxxiii.  43,  535  ; 
increases  in  weight  from  Proscher,  Zeit.  /.  Physiolog.  Chem.,  1S97,  xxiv.  285. 
Reyher,  however  (Abst.  in  Maly's  Jahrbuch  Thier-Chemie,  1906,  xxxv.  308),  took 
mixed  samples  of  the  milk  before  and  after  nursing,  and  found  that  between  the 
115th  and  187th  days  it  contained  from  4-28  to  4-98  per  cent,  of  fat,  whilst 
between  the  208th  and  225th  days,  when  secretion  began  to  fail,  the  percentage 
was  from  49  to  5*98. 


VARIATIONS  IN  HUMAN  MILK  439 

the  mother  certainly  does  not  get  richer  as  the  child  gets  older,  but 
that  the  increasing  demand  for  nutriment  by  the  growing  infant 
is  met  by  supplying  an  increased  quantity  of  milk,  and  not  by 
providing  an  improved  quality. 

This  fact  should  be  noted  by  those  who  have  to'  provide  artificial 
substitutes  for  human  milk.  It  follows,  also,  that  there  is  some 
scientific  justification  for  the  popular  view  that  a  wet-nurse  should 
not  suckle  a  child  which  is  much  younger  than  her  own.  The 
difference,  however,  between  the  composition  of  milk  at  the  third 
week  and  third  month  is  not  sufficiently  great  to  make  such  a 
difference  between  the  ages  of  the  two  infants  a  bar  to  the  employ- 
ment of  the  nurse. 1 

2.  Variations  dependent  on  Individual  Differences  in  the  Mother  or  her 
Child. — These  are  of  comparatively  little  importance.  It  has  been 
found  that  the  milk  of  any  given  woman  will  show  greater  varia- 
tions from  day  to  day  than  the  milk  of  different  women  on  any 
one  day.  Weak  women,  also,  seem  to  furnish  as  good  a  milk  as 
those  who  are  robust  and  strong,  and  the  milk  of  women  who 
have  borne  many  children  is  but  little  poorer  than  that  of  those 
who  are  nursing  their  first  infant.  Age,  also,  has  little  influence, 
for  the  milk  of  women  approaching  the  climacteric  has  not  been 
found  inferior  to  that  of  mothers  hardly  out  of  their  teens. 
Illness,  menstruation,  pregnancy,  fever,  and  even  severe  emotional 
disturbance,  are  also  almost  entirely  devoid  of  any  appreciable 
effect  on  the  composition  of  the  milk.  The  most  striking  fact  about 
the  composition  of  the  milk,  indeed,  is  its  independence  of  outside 
influences.* 

The  fact  that  a  woman  has  a  feeble  child  is  no  proof  that  the  milk 
is  at  fault.  On  the  contrary,  it  was  found  that  the  milk  of  women 
with  feeble  infants  was  rather  richer  than  when  the  suckling  was 
robust.  It  would  almost  seem  as  if  there  was  here  a  provision  of 
Nature  to  supply  the  child  which  has  only  strength  to  draw  a  small 
quantity  of  milk  with  a  food  of  proportionately  better  quality. 

*  See  also  Baumm  and  Illner,  Samml-  Klin.  Vortrdge  (Gyndk.),  1894,  N.F.,  105. 
41.  These  observers  found  considerably  less  difference  in  the  composition  of 
the  milk  at  different  periods  than  was  shown  in  the  later  work  of  Camerer  and 
Soldner.  Monti  {Wietter Klinik,  1897,  Jahrg.  xxiii.,  Hft.  i,  2,  3),  says  that  a  child 
from  one  to  six  weeks  old  should  have  a  wet-nurse  whose  child  is  not  more  than 
two.months.  A  child  from  two  to  four  months  requires  a  nurse  who  has  not  been 
suckling  for  more  than  three  to  four  months.  Whether  for  older  babies  a  younger 
nurse  is  admissible  depends  on  the  age  of  the  child.  A  nurse  whose  own  infant  ia 
two  to  three  months  old^will  do  for  a  child  of  six  to  eight  months,  but  for  a  child 
of  over  three  months  the  milk  of  the  first  weeks  is  insufficient,  and  may  cause 
diarrhoea. 

2  See  Baumm  and  Illner  {loc.  cit.),  on  whose  careful  observations  and  analyses 
most  of  the  above  statements  are  based. 


44°  FOOD  AND  DIETETICS 

3.  Influence  of  the  Mother's  Diet  on  the  Composition  of  her  Milk.— 
Careful  observations  on  this  important  subject  were  made  by  the 
authors  already  quoted  (Baumm  and  Illner).  They  fed  various 
nursing  women  on  the  following  diets,  and  analyzed  the  milk 
produced  on  them  : 

1.  An  ordinary  mixed  diet  taken  in  great  abundance. 

2.  A  highly  nitrogenous  diet — i.e.,  one  containing  much  cheese, 
eggs  and  meat. 

3.  A  diet  rich  in  carbohydrates  and  fat,  but  poor  in  nitrogen— I'.i?., 
plenty  of  bread,  farinaceous  foods,  sugar  and  butter. 

4.  A  very  fluid  diet. 

5.  An  ordinary  diet  plus  2  to  3  pints  of  lager  beer  daily. 

6.  A  diet  consisting  largely  of  salt  fish,  pickles,  and  other  salt 
foods. 

They  found  that,  in  the  main,  fat  was  the  only  ingredient  of  the 
milk  on  which  the  diet  produced  any  appreciable  effect.  It  was 
increased,  sometimes  rising  i  per  cent.,  on  the  first  and  second  diets 
only.  An  abundant  supply  of  carbohydrates  had  no  influence  upon 
the  amount  of  fat.  Nor,  curiously  enough,  had  the  amount  of  fat 
consumed  in  the  food ;  indeed,  an  increased  amount  of  fat  eaten 
seems  to  diminish  rather  than  increase  the  amount  of  cream  in  the 
milk.  These  results  are  in  harmony  with  those  obtained  in  the 
feeding  of  cows,  where  a  bean  diet  produces  more  and  richer  milk 
than  any  other,  and  the  amount  of  fat  in  the  food  is  without  effect.^ 
It  is  surprising,  too,  that  an  increased  amount  of  fluid  in  the  diet 
does  not  appreciably  increase  the  total  yield  of  milk.  Nor  did  the 
diet  of  salted  foods  aflect  the  composition  of  the  milk  or  the  health 
of  the  child. 

On  the  whole,  the  results  of  these  and  of  similar  experiments' 
tend  to  show  that  the  composition  of  the  milk  yielded  is  to  a  large 
extent  independent  of  the  diet,  just  as  we  have  seen  it  to  be  of  other 
external  conditions.  Even  if  the  supply  of  food  is  to  a  large  extent 
cut  off,  the  mother  goes  on  producing  milk  just  as  before,  only  at 
the  expense  of  her  own  tissues.  Thus,  it  was  found  that  during  the 
siege  of  Paris  women  were  able*  to  continue  nursing  although 
almost  starved  to  death.  The  influence  of  alcohol  on  the  secretion 
and  composition  of  milk  is  a  subject  of  great  practical  importance.' 
The  experiments  just  quoted  showed  that  2  to  3  pints  of  light 

*  Thomson,  '  Food  of  Animals,'  London,  1846,  p.  132. 

*  See  Temesvary  (Monatsheft  f.  Geb.  u.  Gyndk.,  November,  1900). 

■*  For  an  elaborate  resume  of  our  knowledge  on  this  subject,  see  Rosemann, 
Archiv.  f.  die  Gcs.  ritysiolog.,  1900,  Ixxviii.  466. 


INFLUENCE  OF  MOTHER'S  DIET  44 1 

beer  daily  had  no  effect  on  the  composition  of  the  milk,  and  other 
observers  have  shown  that  as  much  as  five  glasses  of  port  or  cham- 
pagne are  similarly  devoid  of  influence.^  Physiologically  alcohol 
may  be  regarded  as  the  nutritive  equivalent  of  a  certain  amount  of 
fat  (p.  340),  and  as  fat  in  the  diet  is  without  favourable  influence 
on  the  composition  of  the  milk,  so,  too,  is  alcohol.  The  common 
prescription  of  stout  for  nursing  mothers  is  thus  devoid  of  scientific 
justification,  for  the  nutritive  ingredients  of  stout  are  its  alcohol 
and  a  certain  proportion  of  sugar,  and  both  of  these  are  unable  to 
improve  the  quahty  of  the  milk. 

On  the  other  hand,  the  bad  effects  on  the  child,  which  have  been 
attributed  to  the  taking  of  alcohol  by  the  mother,  are  equally 
imaginary,  the  fear  that  alcohol  will  be  excreted  by  the  milk 
being  groundless,  unless,  indeed,  the  mother  indulge  in  it  to  the 
extent  of  producing  intoxication.  Distillation  of  the  milk  in  the 
above  experiments  failed  to  show  the  presence  of  any  alcohol  in  it 
at  all. 

Alcoholic  liquors,  then,  cannot  directly  affect  the  quality  of  the 
milk.  On  the  other  hand,  if  a  little  bitter  beer  or  a  glass  of  wine  at 
meals  increases  the  mother's  appetite  and  her  power  of  digesting 
ordinary  food,  then  such  an  addition  to  her  diet  will  improve  her 
own  nutrition  and  with  it  the  composition  of  her  milk. 

Seeing  that  the  composition  of  the  milk  is  so  little  affected  by 
diet,  one  need  not  jump  to  the  conclusion  that  if  a  suckling  be 
suffering  from  dyspepsia  there  is  some  error  in  the  mother's  food. 
So  long  as  the  proportion  of  fat  in  the  milk  remains  normal,  it  may 
be  assumed  that  there  is  no  great  fault  in  the  dietary  of  the  mother. 
On  the  other  hand,  if  the  milk  shows  a  deficiency  of  fat,  the  best 
way  to  improve  its  quality  is  to  increase  the  appetite  of  the  mother 
for  ordinary  food,  to  supply  her  with  that  abundantly,  and  of  an 
easily-digested  quality,  to  let  her  have  four  meals  daily,  and  to  see 
that  meat  or  some  other  form  of  protein  food  is  well  represented  in 
at  least  three  of  them. 

4.  Influence  of  Frequency  of  Suckling  on  the  Composition  of  the  Milk. — 
The  act  of  suckling  serves  as  a  stimulus  to  the  breast,  and  if  repeated 
at  too  short  intervals  the  richness  of  the  milk  is  increased,  and  it 
may  become  less  digestible.  Hence,  if  a  child  is  crying  from 
indigestion,  an  attempt  to  quieten  it  by  frequently  giving  it  the 
breast  is  sure  to  lead  in  the  end  to  the  production  of  an  even  less 
digestible  milk,  and  so  to  an  aggravation  of  the  trouble. 

*  Klingeraann,  quoted  by  Cautley. 


442 


FOOD  AND  DIETETICS 


3.  Amount  of  Milk  required  by  the  Child  daily. 

One  can  only  arrive  indirectly  at  the  amount  of  milk  which  a 
child  should  get  at  each  meal  and  in  the  course  of  the  day.     Argu- 
ments from  the  size  of  the  stomach  in  infancy  are  not  of  much 
value,  for  individual  variations  in  the  size  of  the  stomach  are  very 
wide,  and  the  size  after  death  is  no  certain  criterion  of  the  capacity 
during  life.     Nor  is  the  amount  of  milk  in  the  breast  a  certain 
guide,  for  the  child  need  not  exhaust  the  breast  at  each  meal.     A 
method  which  has  been  widely  adopted  is  that  of  carefully  weighing 
the  child  before  and  after  each  feed.     If  carried  out  on  a  sufficiently 
large  number  of  infants,  this  method  affords  a  fairly  trustworthy 
basis  from  which  to  arrive  at  the  average  quantities  required  at  each 
age,  and  it  is  by  such  a  method  that  the  following  tables  have  been 
constructed.* 


AMOUNT  OF  MILK  REQUIRED  DAILY  (CAMERER). 

Period. 

Quantity  in  Twenty- 
four  Hours. 

Period. 

Quantity  in  Twenty 
four  Hours. 

ist  day         ,. 

,.       30  grammes. 

gth  week     . 

..     817  grammes. 

2nd,, 

..     130         „ 

loth     ,, 

..     850        „ 

3rd,, 

..     240         „ 

nth     ,, 

..     764        „ 

4th  „ 

..     290        ,, 

i2:li     „ 

..     767        „ 

5th  „ 

..     330         „ 

13th     ,, 

..     819        „ 

Gth  „ 

..     365         ., 

14th     ,, 

..     829        „ 

7th  ,, 

..     400 

13th     ,, 

..     838        „ 

Middle  of  2nd  w 

eek      450        „ 

loth     ,, 

..     843        „ 

End 

„          500        >> 

17th     ,, 

..     851 

3rd  week 

. .     497         „ 

iSth     ,, 

••     875        ,. 

4th     „ 

•  ■      5«2 

19th     ,, 

..     872        „ 

5th     „ 

..     653 

20th     ,, 

..     820        „ 

6th     „ 

.•      734 

2ISt       ,, 

..     862 

7th     „ 

..     7S0         „ 

22nd     ,, 

..     848        „ 

Bth     „ 

..     803         „ 

AMOUNT  OF  MILK  REQUIRED  DAILY— AVERAGE  MEALS 

(FEER).2 


Period. 

Quar 

tity. 

Per  Day. 

ist  week 

40  to    50  grammes. 

291              grammes 

2nd     ,, 

80  ,,    go 

„ 

549 

3rd  to    4th  week 

85  ,,  110 

•  I 

590  to  C52 

5th  .,    8th     „ 

120  ,,  135 

M 

687  ,,  804 

gth  ,,  i2th     ,, 

140 

f 

815  .,  828 

13th  ,,  i6th     „ 

150 

•t 

852  ..  893 

17th  ,,  20th     „ 

155 

*• 

902  „  947 

2TSt   ,,  24th      „ 

160 

•  f 

956  ,,  g8o 

1  It  must  be  noted  that  the  amount  taken  from  the  breast  at  any  one  mea 
varies  greatly,  and  this  invalidates  considerably  the  trustworthiness  of  the  'tes. 
meal  '  as  an  index  of  the  total  daily  consumption  (see  Forsyth,  'Observations, 
on  Breast  Feeds,'  Lancet,  June  24,  1913)- 

•  Quoted  by  Hauser,  ForUchr.  der  Med.,  1897,  xv.  929. 


AMOUNT  OF  MILK  REQUIRED  DAILY  443 


AVERAGE  MEALS  IN  ELEVEN  BOTTLE-FED  BABIES 
(SCHMID-MONNARD).i 

„    .   .  Quantity  taken  at 

P"'""^'  ^  Each  Meal. 

xst  to    4th  week      .,         ••         ••  185  c.c. 

5th  ,.    8th  , 215    „ 

gth  ,,  i2th  ,,         230    ,, 

13th  ,,  i6th  ,,         260    ,, 

17th  ,,  20th 270    „ 

2ist    ,,  24th  ,,         ..         ..         ..  270    „ 

25th  ,,  28th 290    ,, 

29th  ,,  32nd    ,,         330    ,, 

33rd  ,,  36th 380    ,, 

37th  ,,  40th 310    ,, 

41st   .,  44th 350    .. 

The  last  observer  found  that  the  quantity  taken  at  a  meal  usually 
surpasses  the  capacity  of  the  stomach,  the  explanation  of  which 
probably  is  that  the  stomach  begins  to  empty  itself  before  the  meal 
is  finished.* 

Obviously  these  data  must  only  be  regarded  as  affording  average 
indications.  They  must  not  be  applied  too  absolutely  to  any  given 
child,  for  small  and  weakly  children  will  necessarily  require  less 
nutriment  than  those  which  are  heavy  and  strong,  and  healthy 
infants  of  a  few  weeks  may  take  as  much  milk  as  feebler  ones  whose 
age  is  counted  by  months.  Pritchard  has  also  pointed  out  that  the 
amount  of  food  required  by  an  infant  is  greatly  influenced  by  such 
stimuli  to  metabolism  as  exposure  to  air  and  light.' 

Bearing  these  precautions  in  mind,  then,  one  may  say  that  on  an 
average  a  healthy  infant  will  require — 

During  1st   to  4th  week 600  grammes  milk  daily. 

,,      2nd  ,,  4th  month  ..         ..         ..     800  ,,  ,, 

..      5tli   M  7th     ,,  950 

The  child  will  require  eight  meals  in  the  twenty-four  hours ;  there- 
fore a  wet-nurse  should  yield  from  each  breast  two  or  three  hours 
after  the  last  suckling — 

In  I  St  to  4th  week 40  grammes. 

,,  2nd,,  4th  month  55        ,, 

„  5th  „  7th      ,.  65 

1  Jakrb. /.  Kinderheilk.,  1899,  xlix.  67. 

2  See  also  Feer,  ibid.,  1906,  Ixiv.  355,  and  Mosenthal,  Arch,  of  Pediatrics,  1909, 
xxvi.  761. 

*  Brit.  Journ.  of  Children's  Diseases,  xi,,  1914,  p.  49.  Pritchard  calculates  that 
a  child  of  three  months  weighing  ii  lbs.  should  not  require  less  than  23  02s.  of 
breast-milk  daily ;  one  of  six  months  weighing  16^  lbs.  less  than  30  ozs.,  and  one 
of  Dine  months  less  than  36  ozs.,  daily. 


444 


FOOD  AND  DIETETICS 


The  importance  of  regularity  in  the  feeding  of  infants  cannot  be 
exaggerated.  By  proper  timing  of  the  meals  it  can  be  arranged 
that  the  stomach  shall  have  plenty  of  time  to  empty  itself,  and  thus 
one  cause  of  indigestion  will  be  avoided.  The  child  is  a  creature  of 
habit,  and  if  it  be  trained  to  regular  feeding  hours  will  not  expect 
feeds  between  meals.  The  following  table,  borrowed  from  Holt, 
represents  in  a  convenient  form  the  best  intervals  for  feeding  at 
different  ages,  and  (approximately)  the  amount  of  drink  to  be 
taken  at  each  meal.^  The  table  is  constructed  in  order  to  afford 
guidance  as  to  the  quantities  to  be  given  in  artificial  feeding, 
but  the  same  time  intervals  should  be  observed  when  the  child  is 
being  fed  by  the  breast,  although  in  that  case  the  quantity  taken 
can  usually  be  safely  left  to  be  determined  by  the  appetite  of  the 
child. 

SCHEDULE  FOR  FEEDING  HEALTHY  INFANTS  DURING 
THE  FIRST  YEAR. 


II 

B 

8  . 

u  to 

H 

b  h 

V    *^ 

<£  ™ 

>^u 

.      3 

.Q  >. 

V  a 

.—    9 

Age. 

"o^ 

0 

b.2 

ir"? 

ii 

s- 

^-5 

£B 

•=(2 

vb 

3   * 

V   u 

|2 

Z  0 

0 
3 
c 

eg 

^f 

■^ 

H 

Hours. 

Ounces. 

Grammes, 

Ounces. 

Grammes. 

3rd  to  7th  day 

10 

2 

2 

1-li 

3c^45 

10-15 

310-460 

2nd      and      3rd 

weeks 

10 

2 

3 

ii-3 

45-90 

15-30 

460-930 

4th      and      5th 

weeks 

9 

2 

I 

2^3i 

75-110 

22-32 

680-990 

6th  week  to  3rd 

month 

8 

2i 

I 

3-4i 

90-140 

24-36 

740-1,110 

3rd  to  5th  month 

7 

3 

I 

4-5h 

125-170 

28-38 

870-1,080 

5th  to  gth  month 

6 

3 

0 

5i-7 

170-220 

33-42 

1,020-1,300 

9th      to      I2th 

month 

5 

3i 

0 

7h-9 

235-280 

37-45 

1,150-1,400 

As  in  the  previous  tables,  the  quantities  in  this  case  must  again  be 
regarded  as  only  applicable  to  the  healthy  child  of  average  weight, 
and  may  require  to  be  reduced  somewhat  for  delicate  infants.  There 
are  two  criteria  by  which  one  can  judge  whether  the  amount  given 
is  sufficient :  (i)  the  weight  of  the  child,  (2)  the  character  of  the 
stools.     Regular  weighing  is  of  the  greatest  importance,  and  if  a 

*  Such  a  table  must  be  tised  with  some  elasticity.  In  very  delicate  infants  it 
may  be  necessary  to  feed  at  even  shorter  intervals,  whilst  in  those  which  are 
healthy  it  is  often  possible  to  feed  at  four-hourly  periods  quite  early. 


FOOD  VALUE  OF  HUMAN  MILK  445 

steady  increase  in  weight  be  not  manifest,  there  is  something  wrong 
with  the  diet.  Inspection  of  the  stools  will  show  whether  they 
contain  any  undigested  milk,  and  so  whether  absence  of  increase  in 
weight  be  due  to  deficiency  in  the  amount  of  the  diet  or  to  some 
error  in  its  quality. 

4.  Digestibility  of  Human  Milk. 

Stomach  digestion  is  not  of  much  importance  in  infancy.  The 
stomach  in  early  life  is  small  in  capacity  and  of  but  feeble  muscular 
power,  and  seems  to  allow  the  food  introduced  into  it  to  pass  quickly 
on  into  the  intestine,  where  the  essential  work  of  digestion  takes 
place.  Thus,  it  has  been  found,^  by  washing  out  the  stomachs  of 
infants  at  varying  intervals  after  feeding,  that,  if  3  ounces  of  milk  be 
taken  at  a  meal,  fully  three-fourths  of  it  has  left  the  stomach  after 
the  lapse  of  two  hours,  and  that  in  another  twenty  or  thirty  minutes 
the  stomach  is  entirely  empty. 

Whether  the  milk  really  clots  in  the  stomach  in  very  early  life  is 
disputed,  some  writers  contending  that  there  is  no  rennet  to  be  found 
in  the  stomach  during  the  first  month.  Whether  this  be  so  or  not 
is  of  little  importance,  for  the  clot  formed  by  human  milk  is,  for 
reasons  to  be  explained  later  (p.  451),  very  much  looser  than  the 
clot  formed  by  cow's  milk,  and  does  not  offer  any  serious  difficulty 
to  the  stomach  in  its  digestion. 

The  absorption  of  the  constituents  of  human  milk  in  the  intestine 
of  infants  seems  to  be  very  complete.  Protein  is  said-  to  be  absorbed 
to  the  extent  of  99  per  cent.,  fat  to  97  per  cent.,  and  the  mineral 
salts  to  90  per  cent.,  while  the  sugar  enters  the  blood  in  its  entirety. 
During  the  first  week  or  so  of  life,  however,  the  absorption  of  the 
fat  of  the  milk  does  not  seem  to  be  always  as  perfect  as  these  figures 
would  indicate,  and  a  good  deal  of  fat  may  be  found  in  the  motions.' 
It  would  seem,  indeed,  as  if  the  newly-born  infant  required  a  little 
practice  before  it  is  able  thoroughly  to  digest  even  its  mother's  milk. 

5.  Nutritive  Value  of  Human  Milk. 

Comparing  the  nutritive  value  of  a  given  amount  of  human  milk 
with  that  of  an  equal  quantity  of  cow's  milk,  one  may  say  that  the 
two  yield  practically  the  same  a'-^ount  of  solid  nutriment;  but  the 
fuel  value  of  the  cow's  milk  is  rather  greater  than  that  of  human 

1  Van  Puteren  (Diss.  St.  Petersburg,  1889),  reference  in  Jahrb.  /.  Kinderhriik., 
1890,  xxxi.  188. 
*  Uffelmann,  Deut.  Archiv.  /.  Klin.  Med.,  i88i,  xxviii.  437. 
»  See  Blauberg,  '  Studien  iiber  Sauglingsfaces, '  Berlin,  1897. 


446  FOOD  AND  DIETETICS 

milk,  owing  to  the  larger  amount  of  fat  which  it  contains.     The 

difference,  however,  is  not  great,  for  loo  grammes  of  cow's  milk 

yield  66  Calories,  and  a  similar  quantity  of  human  milk  62J  Calories. 

Both  in  building  material  and  in  fuel  value,  therefore,  human  milk 

is  a  poorer  fluid  than  the  milk  of  the  cow.^ 

An   ordinary   infant,  six   months   of  age,    consuming   the   usual 

amount   of  breast-milk,    will   get   from   it,   roughly   speaking,   the 

following  amounts  of  nutritive  materials  : 

Protein         14  grammes. 

Fat 30 

Carbohydrates       59        <• 

These  quantities   may  be  compared  with   the   standard   for  an 
ordinary  man  doing  moderate  work  thus: 


Adult  at  Moderatt 

Infant  of 

Work  (Voit). 

Six  Months. 

{Weight 

{Weight 

■=70  Kilos.) 

=  67  Kilos.) 

Protein           « . 

118 

14 

Fat 

56 

30 

Carbohydrate 

•  •         500 

59 

Calories 

••      3.054 

578 

This  comparison  is  also  exhibited  in  a  graphic  form  in  Fig.  33. 
One  is  at  once  struck  by  the  relatively  large  amount  of  fat  which 
the  diet  of  human  milk  contains.  The  infant  of  six  months  actually 
obtains  more  than  half  as  much  of  that  constituent  as  the  full- 
grown  man.  The  relation  of  protein  to  carbohydrate  in  the  two 
diets  is  very  similar,  but  it  must  be  remembered  that  the  man  is 
doing  muscular  work,  while  the  infant  is  not.  Relatively  to  weight 
and  mode  of  life,  therefore,  the  infant  is  much  more  abundantly 
nourished  than  the  adult.' 

It  will  be  seen,  too,  that  a  nursing  mother  yields  up  about  one- 
eighth  of  the  protein  and  carbohydrate  in  her  diet  to  her  child,  and 
fully  one-half  of  the  fat,  whilst  more  than  one-fifth  of  the  fuel  value 

1  The  direct  observations  of  Rubner  show  that  i  litre  of  human  milk  yielded  in 
one  instance  614-2  Calories,  and  in  another  723-9.  A  similar  quantity  of  cow|s 
milk  yields  690-4.  In  other  words,  an  average  sample  of  either  human  or  cow's 
milk  may  be  expected  to  yield  close  on  700  Calories  per  litre.  Under  the  most 
favourable  conditions  in  the  adult,  only  90  per  cent,  of  this  is  available,  owing  to 
defective  absorption,  whereas  in  the  infant,  in  which  the  digestion  of  milk  is  more 
perfect,  91  to  91-6  per  cent,  is  available. 

a  The  surface  of  the  child  is  relatively  three  times  as  great  as  that  of  the  adult. 
The  following  table  (from  Camerer)  shows  the  relation  between  extent  of  surface 
and  the  Calories  supplied  in  the  diet  at  different  periods  of  life  : 

In/ants. 

Age  in  weeks 2  7  14  20  59 

Weight  in  kilos 3  42  5  3  63         10-3 

Calories  per  square  metre  of  surface     1,020         1.420       1,330       1,270       1,390 


INFANT  AND  ADULT  DIET  CONTRASTED        447 

of  her  food  is  also  handed  over  to  the  infant.  The  chemical  energy 
which  a  mother  expends  daily,  therefore,  in  nursing  an  infant  six 
months  of  age  would  be  sufficient  to  raise  a  ton  weight  about  800 

80S4 
CALORIES 


CARBOHYDRATE 


l»T. 


PROTEIN. 


5T8 

cALOfttes 


CMIO^ 


moniig 


50 


^30  I 


Fig.  33 —Comparison  of  Ndtritive  Constitdents  required  by  an 
Adult  and  by  an  Infant  of  Six  Months. 

feet  high,  or  more  than  twice  as  high  as  the  top  of  the  dome  of 

St.  Paul's.1 


Boys. 

Age  in  years 3  to  5  7  to  10 

Weight  in  kilos.          ..         ..         ..           18  24 

Calories  per  square  metre  of  surface     1,680  1.440 


II  to  14  15  to  r6 

34  52  ..  58 

1,250  1, 220 


Adults. 

Weight  655  kilos. 

Calories  (rest)  1,190 

,,        (work)         1,420 

Immediately  after  birth,  therefore,  a  child  gets  a  smaller  supply  of  Calories  per 
square  metre  than  an  adult,  and  consequently  loses  in  weight,  but  later  on  it  gets 
more  per  surface  area,  and  is  thus  able  to  grow. 

*  This,  of  course,  is  assuming  that  the  whole  potential  energy  of  the  milk  could 
be  converted  into  work. 


[44S  J 


CHAPTER  XXV 

THE    PRINCIPLES    OF    FEEDING    IN    INFANCY   AND 

CHILDHOOD  {continued) :  SUBSTITUTES  FOR 

HUMAN  MILK 

In  the  last  chapter  we  learnt  that  the  physiological  pecuharities  of 
infancy  demand  that  the  diet  during  that  period  of  life  should  be 
relatively  rich  in  protein  and  mineral  matter,  and  especially  so  in 
fat.  A  consideration  of  the  chemical  composition  of  human  milk 
showed  how  well  adapted  it  is  to  meet  these  demands,  while  a  com- 
putation of  the  amount  of  it  which  infants  consume  at  different  ages 
enabled  us  to  form  some  idea  of  the  quantity  of  each  nutritive 
ingredient  actually  required  at  each  period  of  infancy.  Further 
investigation  taught  us  that  human  milk  is  easily  disposed  of  by  the 
infant's  stomach,  is  absorbed  very  completely  in  the  intestine,  and  is 
a  fluid  of  high  nutritive  value,  and  therefore  eminently  adapted  for 
the  requirements  of  the  child. 

These  results  of  scientific  investigation  have  been  long  anticipated 
by  experience,  and  both  unite  to  emphasize  the  inestimable  value  to 
the  infant  during  the  first  ten  months  at  least  of  its  life  of  a  dietary 
of  human  milk.  Unfortunately,  however,  the  mother  is  often 
unable  or  unwilling  to  suckle  her  infant,  and  one  has  to  find  some 
substitute  for  the  natural  supply.  A  wet-nurse  is,  of  course,  from 
the  infant's  point  of  view,  the  best  alternative,  but  one  need  hardly 
say  that  this  mode  of  feeding  is  open  to  considerable  practical 
disadvantages.  One  naturally  looks  next  to  the  milk  of  other 
animals.  The  following  table  exhibits  the  approximate  composition 
of  the  milk  of  some  of  the  commoner  domestic  animals  compared 
with  that  of  human  milk  : 


MILK  OF  DOMESTIC  ANIMALS 


449 


COMPOSITION  OF  THE  MILK  OF  DIFFERENT  ANIMALS.* 
loo  Grammes  Milk  contain  in  Grammes 


Protein. 

Fat. 

Sugar. 

Ash. 

Other  Nitrogenous 
and  Unknown  Bodies 

Human   .. 

09 

352 

675 

019 

06 

Cow 

30 

3-55 

4'5i 

070 

0-3 

Goat        . . 

2-8 

3-40 

380 

095 

Mare 

19 

100 

6-33 

045 

049 

Ass          .. 

16 

093 

5  60 

036 

It  will  be  observed  that  none  of  these  is  identical  with  human 
milk. 

This  is  not  surprising,  for  the  composition  of  a  milk,  especially  as 
regards  its  proteins  and  mineral  constituents,  seems  to  depend  upon 
the  rate  of  growth  of  the  animal  for  which  it  is  intended.  The 
faster  a  young  animal  grows,  the  richer  is  the  mother's  milk  in  these 
two  ingredients.  This  fact  is  brought  out  very  strikingly  in  the 
following  table  :^ 

100  Parts  Milk  contain 


Human 
Horse 
Calf  .. 
Goat  . . 

Pig    .. 

Sheep 
Cat     .. 
Dog   .. 
Rabbit 


Time  by  which 
Weight  is  Doubled. 

1 80  days 
60  ,. 
47  .. 
19  .. 
18  „ 
10  „ 
9h  ., 


r 
rofein. 

Ash. 

Lime. 

Phosphoric  Acid 

10 

02 

0032 

0047 

20 

04 

0124 

0131 

35 

07 

0  160 

0197 

43 

08 

0210 

0322 

59 

— 

— 

— 

6-5 

09 

0272 

0-412 

70 

10 

— 

— 

73 

13 

0453 

0493 

104 

24 

o-8gi 

0996 

The  milk  of  the  ass  has  often  been  stated  to  be  the  closest 
approximation  to  mother's  milk.  I  have  collected  the  results  of  all 
the  most  recent  analyses  of  it,  and  compared  them  with  the  standard 
of  composition  of  human  milk  as  follows  : 


Ass's  Milk 
{Schlossmann's 

Ellenherger's 
Analysis. 

Average 
other 

of 

Human  Milk.* 

Analysis).' 

A  nalyses 

4 

Water 

88-80 

— 

90-5 

8760 

Protein         . . 

1-30 

1*2  to  17 

19 

1-52 

Fat    .. 

0-36 

o'l  .,  17 

I '4 

328 

Sugar 

4*94 

5  ..  6 

6-3 

650 

Mineral  matter 

0-309 

03  ..  0-4 

0-4 

027 

It  will  be  observed  that  ass's  milk  is  poorer  in  every  ingredient 
except,  perhaps,  protein  and  mineral  matter.  It  is  especially  poor 
in  fat,  which  is  so  important  to  the  infant.     In  addition  to  this  it  is 

1  Heubner,  '  Ueber  Milch  und  Milchpraparate,'  Zeit.  /.  Didt.  und  Physik. 
Therapie,  1899,  iii.  i. 

2  Heubner,  Zeit.  f,  Diat.  und  Physik.  Therapie,  1899,  iii.  i. 

*  Schlossmann,  Zeit.f.  Physiolog.  Chem.,  1897,  xxiii.  258. 

*  Dujardin  Beaumetz,  W^'nter  Blyth,  Peligot,  Cheadle. 
'  Camerer  and  Soldner,  loc.  cit. 

29 


450  FOOD  AND  DIETETICS 

stated  to  be  slightly  laxative  in  its  effects,  and  contains  relatively 
more  casein  and  less  albumin  than  human  milk,  but  it  resembles  the 
latter  in  leaving  no  residue  of  nuclein  or  paranuclein  on  digestion 
and  in  having  an  alkaline  reaction.  It  is  expensive  also,  and 
difficult  to  obtain,  although  one  at  least  of  the  large  London  dairy 
companies  now  keeps  a  stock  of  milch  asses  for  the  purpose  of  supply- 
ing it.^  On  the  whole,  it  cannot  be  said  to  be  in  any  way  superior 
to  the  modifications  of  cow's  milk  which  will  be  dealt  with  later. 

The  same  remarks  are  applicable  to  mare's  milk  as  to  ass's, 
except  that  the  former  is  richer  in  sugar.  Goat's  milk  is  a  com- 
paratively strong  milk  and  not  any  better  suited  for  use  in  infancy 
than  cow's. 

In  the  vast  majority  of  cases,  then,  cow's  milk  must  be  the 
substitute,  and  hence  a  careful  study  of  the  differences,  chemical 
and  physiological,  between  it  and  human  milk  is  a  matter  of  the 
first  importance. 

Chemical  Differences  between  Human  and  Cow's  Milk. 

{a)  Quantitative  Differences. — Taking  the  average  results  of  a  great 
number  of  observations  on  the  general  chemical  composition  of  the 
two  milks,  one  may  compare  them  thus: 

Human  Milk.  Cow's  Milk. 

Water 87  to  88  per  cent  87  to  88  per  cent. 

Protein..         ..         .,  i  ,,     2       ,,  3   .•     4       ,, 

Fat        3  ..     4       ..  3i..     4i     ., 

Sugar 6,.     7       „  4   ..     5       ., 

Mineral  matter          ..  o'l  ,,  0-2      „  07         „ 

Reaction         ..         ..  Alkaline.  Acid. 

One  sees  that  while  the  total  amount  of  solids  in  the  two  kinds  of 
milk  is  about  the  same,  yet  the  relative  proportions  of  the  different 
constituents  in  the  two  cases  are  very  different.  Cow's  milk  is  the 
richer  in  protein,  mineral  matter,  and  (to  a  less  degree)  in  fat ; 
human  milk  excels  in  sugar.  The  superiority  of  cow's  milk  in  the 
building  materials  is  no  doubt  due  to  the  more  rapid  rate  of  growth 
of  the  calf  than  of  the  infant,  but  the  excess  of  carbohydrate  in 
human  milk  is  rather  surprising  when  one  compares  the  relative 
muscular  activities  of  the  calf  and  the  baby.  It  suggests  that  some 
of  the  sugar  in  human  milk  is  intended  as  a  weak  form  of  fuel 
instead  of  the  more  powerful  heat-producing  fat,  and  this  substitution 
may  be  due  to  human  milk  having  been  devised  as  an  infant  food 

»  Asses  very  rarely  suffer  from  tuberculosis,  so  that  the  use  of  their  milk  is  to 
some  extent  a  safeguard  against  that  disease. 


HUMAN  VERSUS  COW'S  MILK  45* 

suited  to  a  warmer  climate  than  that  which  civilized  man  now 
occupies. 

The  proportion  of  lecithin  is  also  relatively  much  greater  in  human 
than  in  cow's  milk,  there  being  3*05  parts  of  lecithin  to  every  100 
parts  of  protein'in  the  former,  and  only  1*40  to  100  of  protein  in  the 
latter.  This  is  probably  to  be  attributed  to  the  relatively  greater 
weight  of  the  brain  in  the  child  than  in  the  calf.^ 

(b)  Qualitative  Differences. — On  more  closely  examining  cow's  milk, 
one  finds  that  the  differences  in  kind  between  its  principal  ingredients 
and  those  of  human  milk  are  even  greater  than  the  differences  in 
the  relative  amounts.  Sugar,  indeed,  is  the  only  ingredient  which 
is  identical  in  kind  in  the  two  milks ;  the  nitrogenous  matters,  the 
fat  and  the  mineral  salts  must  be  compared  separately  in  each. 

I.  Nitrogenous  Matters. — We  have  already  seen  that  human  milk 
includes  a  considerable  proportion  of  unknown  '  extractive '  bodies 
which  contain  nitrogen.  Cow's  milk  contains  considerably  less  of 
these.  One-eleventh  of  the  total  nitrogen  in  human  milk  is  present 
in  the  form  of  extractives,  as  compared  with  one-sixteenth  in  cow's 
milk.2  As  to  the  uses  of  these  extractives  to  the  child  we  are 
entirely  in  the  dark,  but  it  is  conceivable  that  too  low  a  proportion 
of  them  in  the  diet  may  not  be  free  from  disadvantages. 

The  proteins  of  milk  are  of  two  kinds,  casein  and  albumin 
(Chapter  VII.).  Cow's  milk  contains  relatively  much  more  of  the 
former,  and  human  milk  of  the  latter.  The  exact  proportions  given 
by  different  analysts  vary  considerably,  but  a  reliable  estimate  has 
given  4  parts  of  casein  to  i  of  albumin  in  cow's  milk,  and  the 
proportions  of  the  two  in  human  milk  as  equal.^  When  one 
remembers  that  albumin  is  a  much  more  easily  digested  form  of 
protein  than  casein,  it  is  evident  that  there  is  here  an  important 
practical  difference  between  the  two  milks.  Not  only  so :  the  casein 
itself  is  actually  different  in  the  two  forms  of  milk.  Cow's  casein 
leaves  behind  an  indigestible  residue  (paranuclein) ;  human  casein 
does  not.*  When  an  acid  is  added  to  cow's  milk  the  casein  is 
thrown  down  in  large  flocculi,  which  do  not  readily  dissolve  in 
excess ;  under  similar  treatment  human  milk  yields  very  fine 
flocculi  which  readily  go  into  solution  on  adding  more  acid.      Lastly, 

1  Burow,  •  Der  Lecithingehalt  der  Milch  und  seine  Abhangingkeit  vom  rela- 
tiven  Hirngewicht  des  Sauglings,'  Zeit.  j.  Physiolog.  Chemie,  1900,  xxx.  495. 

^  See  Munk,  Virchow's  Archiv.,  1893,  cxxxiv.  501  ;  and  Camerer  and  Soldner, 
Zeit.  f.  Biolog.,  535,  1896. 

»  Hammarsten,  Jahres-Ber.  f.  Thier-Chemie,  1895,  p.  206.  For  other  estimates 
see  Edlefsen,  Munch.  Med.  Woch.,  xlviii.  7,  901  ;  and  Van  Slyke,  New  York  Med. 
Journ.,  May  25,  1907. 

*  Szontagh,  Utigai.  Archiv.  /.  Med,.  1894  (reference  m  Jahres-Ber.  f.  Thier-Chemie. 
1894,  xxiv.  209). 


452  FOOD  AND  DIETETICS 

human  casein  is  richer  in  sulphur  than  the  casein  of  cow's  milk. 
For  these  reas'ons  human  casein  is  more  easily  digested. 

2.  Fat. — The  fat  of  human  milk  contains  more  oleic  acid,  and 
has  consequently  a  lower  melting-point  and  is  more  easily  digested 
than  the  fat  in  cow's  milk.  This  greater  digestibility  of  the  fat  of 
human  milk  is  increased  by  the  fact  that  it  is  present  in  a  much 
finer  state  of  division  than  the  fat  droplets  in  cow's  milk.  Human 
milk  fat  contains  also  much  less  of  the  soluble  or  volatile  fatty  acids 
than  one  finds  in  the  fat  of  cow's  milk^ ;  the  exact  significance  of 
this  is,  however,  unknown. 

3.  The  mineral  salts  in  the  two  forms  of  milk  also  show  important 
differences.  Not  only  are  calcium  and  phosphorus  both  present  in 
much  smaller  amount  in  human  milk,  but  there  are  important 
differences  in  the  form  in  which  the  phosphorus  occurs  in  the  two 
cases.  In  human  milk  there  is  only,  or  almost  only,  organically 
combined  phosphorus  present ;  in  cow's  milk  less  than  half  is  in  this 
form  of  combination.^  In  its  high  proportion  of  organic  phosphorus 
human  milk  recalls  the  chemical  peculiarities  of  plant  embryos  or 
the  yolk  of  egg.  Considering  the  great  importance  of  phosphorus 
in  the  nutrition  of  the  infant,  and  the  fact  that  organic  combinations 
of  it  are  probably  more  easily  assimilated  than  its  inorganic  salts,  one 
must  admit  that  the  differences  between  human  and  cow's  milk  just 
pointed  out  are  not  to  be  lightly  disregarded. 

In  the  light  of  these  facts,  regarding  the  profound  qualitative 
differences  in  chemical  composition  between  human  and  cow's  milk, 
one  must  conclude  that  it  is  impossible  ever  so  to  modify  the  latter 
that  it  shall  be  identical  with  the  former.  In  other  words,  a  truly 
*  humanized '  cow's  milk  is  a  chemical  impossibility. 

Comparative  Digestibility  of  Cow's  and  Human  Milk. 

It  is  a  familiar  fact  that  most  young  infants  have  much  greater 
difficulty  in  digesting  cow's  milk  than  that  of  their  own  mother. 

1  Laves,  Zeit.f.  Physiol.  Chem.,  1894,  xix.  369,  and  Ruppel,  Zeit,  f.  Biol.,  1895, 
xxxi.  I. 

*  Of  the  total  phosphoric  acid  in  human  milk,  35  per  cent,  is  in  the  form  of 
lecithin. 

Of  the  total  phosphoric  acid  in  cow's  milk,  5  per  cent,  is  in  the  form  of  lecithin. 

Of  the  total  phosphoric  acid  in  human  milk,  41  per  cent,  is  in  the  form  of 
phosphocarnic  acid. 

Of  the  total  phosphoric  acid  in  cow's  milk,  6  per  cent,  is  in  the  form  of 
phosphocarnic  acid. 

See  Siegfried,  Zeit.  f.  Physiol.  Chem.,  1896,  xxii.  575  ;  and  Stoklasa,  ibid., 
1897,  xxiii.  343. 

Sikes  (Journ.  of  Physiol.,  1906,  xxxiv.  464)  finds  that  not  quite  half  the  total 
phosphoric  acid  of  human  milk  is  combined  with  protein.  The  ratio  of  protein 
calcium  to  total  calcium  is  as  84  to  100, 


HUMAN  VERSUS  COW'S  MILK  +53 

The  chief  reason  for  this  is  that  cow's  milk  forms  a  much  denser 
clot  in  the  stomach  than  human  milk.^ 

The  greater  density  of  the  clot  is  due — (i)  to  the  absolutely  larger 
proportion  of  casein  in  cow's  milk,  and  probably  also  to  those 
chemical  differences  between  cow's  and  human  casein  already  men- 
tioned ;  (2)  to  the  smaller  proportion  of  fat  and  soluble  albumin 
relative  to  the  casein  which  characterizes  cow's  milk — the  soluble 
albumin  and  fat  of  human  milk  seem  to  act  mechanically  in  pro- 
ducing a  loose  clot ;  (3)  to  the  fact  that  cow's  milk  contains  six  times 
as  much  calcium  and  three  times  as  much  acid  as  human  milk,  and 
the  density  of  the  clot  depends  very  much,  as  was  explained  in 
Chapter  VII.,  on  the  proportions  of  these  two  constituents. 

For  all  these  reasons  cow's  milk  tends  to  form  a  dense,  retracted 
clot  in  the  stomach,  while  the  clot  of  human  milk  is  loose,  friable, 
and  easily  broken  up. 

In  the  intestine  there  is  much  less  difference  in  behaviour  between 
the  two  milks.  The  stools  of  infants  fed  on  cow's  milk  are  richer 
in  mineral  matters  than  those  of  breast-fed  children,  but,  then,  so  is 
the  milk  on  which  the  latter  are  fed.  A  higher  proportion  of  the 
fat  of  cow's  milk  also  escapes  digestion  than  is  the  case  with  human 
milk,  and  probably  also  a  somewhat  greater  proportion  of  protein  ; 
certainly  the  faeces  of  bottle-fed  babies  contain  more  nitrogen  than 
those  of  infants  reared  at  the  breast. 

Infant  Feeding  with  Cow's  Milk. 
Notwithstanding  the  pronounced  differences  in  chemical  composi- 
tion and  physiological  behaviour  between  cow's  and  human  milk,  there 
are  some  healthy  infants  who  can  be  reared  on  the  former  without 
modification. 3  This  is  known  as  Budin's  method.  In  order  to  carry 
it  out  successfully  the  milk  must  be  sterilized  at  212°  F.  for  forty 
minutes,  and  should  be  given  in  smaJl  feeds,  the  exact  amount  being 
controlled  by  regular  weighing  of  the  infant.  As  a  rule,  the  infant 
will  require  about  one-tenth  to  one-seventh  of  its  weight  of  milk 
daily,  this  being  administered  in  divided  quantities  at  the  usual 
intervals.  As  the  child  gets  older  the  amount  at  each  feed  is 
increased,  while  the  duration  of  sterilization  is  shortened. 

1  Meyer  (Abst.  in  Maly's  Jahrb.  Thiey-Chemie,  1906,  xxxvi.  676),  however, 
believes  that  he  has  shown  that  it  is  not  the  casein  of  cow's  milk  which  is  the 
cause  of  difficulty  to  the  infant,  but  some  constituent  of  the  whey. 

2  See  Blauberg,  'Studien  iiber  Sauglingsfaces,"  pp.  107,  108  ;  Berlin,  1897. 

3  Budin,  Bull,  de  I'Acad.  de  Med.,  1893,  3™*  ser.,  xxx.  157  ;  ibid.,  1894,  3""'  ser., 
xxxii.  67.  For  a  summary  of  the  results  yielded  by  Budin's  method  and  a 
criticism  of  it,  see  Marfan,  'Traite  de  I'Allaitement,'  p.  313  ;  Paris,  1S99.  It  is 
perhaps  better  to  citrate  the  undiluted  milk  (see  Mann,  '  The  Feeding  of  Babies 
with  Undiluted  Citrate  Milk,'  Clin.  Journ.,  1914,  xliii.  691). 


454  FOOD  AND  DIETETICS 

The  method  has  the  great  advantage  of  simplicity  and  of  practically 
ensuring  satisfactory  growth  and  the  absence  of  rickets.  The  fear 
that  it  may  result  in  scurvy  has  been  exaggerated.  In  many  cases, 
however,  and  certainly  by  all  feeble  infants,  pure  cow's  milk  will 
be  found  difficult  of  digestion,  and  requires  some  modification  to 
render  it  suited  to  the  digestive  capacity. 

One  way  in  which  this  has  been  done  is  by  the  process  of 
'  homogenization,'  a  mechanical  process  which  reduces  the  fat  to  a 
state  of  fine  emulsion,  thus  preventing  the  cream  from  rising.  Milk 
so  treated  clots  like  human  milk,  and,  owing  to  this  and  to  the  fine 
division  of  the  fat  globules,  it  is  very  easily  digested.^ 

From  what  has  been  already  said,  it  is  evident  that  any  modifi- 
cation can  only  affect  the  quantities  of  the  different  ingredients  in 
the  milk ;  the  distinctive  peculiarities  of  the  ingredients  as  opposed 
to  those  of  human  milk  will  still  remain.  By  suitable  treatment, 
however,  the  proportion  of  casein,  calcium,  and  acid  salts  present 
can  be  reduced,  and  the  digestibility  of  the  milk  proportionately 
raised.  We  must  now  consider  briefly  the  different  methods  by 
which  this  can  be  done. 

I.  The  simplest  method  is  by  mere  dilution.  The  problem 
here  is  to  reduce  the  casein  and  mineral  matters  in  the  cow's 
milk,  to  leave  the  proportion  of  fat  much  as  it  was,  and  at  the 
same  time  to  increase  the  amount  of  sugar.  Taking  the  average 
composition  of  cow's  and  human  milk,  and  adding  i  part  of  water 
to  I  of  cow's  milk,  we  get  the  following  comparative  results  : 


Protein     ..        •• 

Human  Milk. 
I  "5 

Cow's  Milk, 
3"5 

Cow' 

s  Milk  and  Water, 
equal  parts. 
175 

Fat 

3*5 

40 

2-0 

Sugar 

Mineral  matter   . . 

6-5 

0-2 

45 
07 

225 

This  makes  the  proportion  of  protein  about  right,  but  leaves  the 
fat  and  the  sugar  too  low.  If  now  one  adds  to  every  4  ounces  of 
the  mixture  i  medium-sized  teaspoonful  of  milk-sugar^  pressed  flat 
and  I  teaspoonful  of  ordinary  centrifugal  cream,  these  defects  are 
rectified,  and,  except  for  an  excess  of  mineral  matter,  the  mixture 
will  have  approximately  the  same  proportion  of  each  ingredient  as 
human  milk.  The  digestibility  of  such  a  mixture  is  still,  however, 
inferior  to  that  of  milk  from  the  breast,  for  water  in  this  proportion 
does  not  prevent  the  formation  of  a  rather  dense  clot  in  the  stomach. 

^  Homogenized  milk  is  made  at  the  Lepelletier  factory  at  Carentan  (Manche), 
France,  and  can  be  obtained  in  a  sterilized  form  from  Roberts  and  Co.,  76,  New 
Bond  Street,  W. 

*  White  cane-sugar  will  also  do,  but  milk-sugar  is  better.     . 


MODIFICATION  OF  COW'S  MILK  455 

For  this  reason  it  is  better  to  dilute  with  lime-water  or  barley-water 
rather  than  with  plain  water. 

The  digestibility  of  the  casein  can  also  be  increased  by  the  addition 
of  citrate  of  soda  in  the  proportion  of  i  grain  to  every  ounce  of  cow's 
milk.*  This  acts,  as  has  been  already  pointed  out,  by  precipitating 
the  excess  of  calcium  salts,  and  so  causing  the  casein  to  set  into  a 
less  dense  curd  in  the  stomach. 

In  the  case  of  very  young  or  weakly  infants,  it  may  be  necessary 
to  dilute  the  milk  more  freely  than  in  the  proportion  given  above. 
In  such  a  case  a  mixture  of  equal  parts  of  milk,  water,  and  lime- 
water  is  to  be  recommended,  cream  and  sugar  being  added  in 
proportionately  larger  quantity. 

An  ingenious  method  of  overcoming  the  casein  difficulty  has  been 
proposed  by  Von  Dungern.^  It  consists  in  boiling  the  milk,  cooling 
to  40°  C,  and  adding  some  pure  rennin.  Clotting  takes  place  in 
two  or  three  minutes,  and  the  milk  is  then  thoroughly  shaken  until 
all  clots  have  disappeared.  It  is  then  ready  for  use.  By  this 
method  the  casein  is  not  further  clotted  on  reaching  the  stomach, 
and  is  therefore  very  easily  digested.  A  combination  of  rennin  and 
milk-sugar  for  use  in  the  process  is  sold  under  the  name  of  Pegnin.' 

2.  More  elaborate  methods  are  the  cream  mixtures  of  Meigs,  Rotch, 
and  Biedert. 

Meigs*  allows  a  quart  of  milk  to  stand  for  three  hours  in  a  cool 
place  in  a  tall  vessel.  At  the  end  of  that  time  he  carefully  decants 
the  upper  half  of  the  milk,  which  is  now  rich  in  cream.  To  every 
i^  ounces  of  this  he  adds  i  ounce  of  lime-water  and  i|^.  ounces  of 
sugar-water,  which  is  made  by  dissolving  8  heaped  teaspoonfuls  of 
milk-sugar  in  16  ounces  of  water.  This  mixture  will  obviously  be 
poorer  in  protein  than  that  described  above.  The  same  principle 
is  adopted  in  the  modification  of  milk  by  the  '  Lupa '  or  *  Reed  ' 
Humanizer,  both  of  which  are  suitable  for  domestic  use. 

Rotch's  formula'^  is  very  similar.     He  takes 

Cream  (20%  fat)  ..     i^  ounces.    I   Water..         ,.         ,.     5  ounces. 

Milk        ..         ..         ..     I  ounce.       |   Milk-sugar     ..         ..     3I  drachms. 

The  mixture  is  boiled,  and  when  cool  ^  ounce  of  lime-water  is 
added.     It  is  stated  to  have  the  following  composition : 

1  See  a  paper  by  Dr.  F.  J.  Poynton  ('  The  Value  of  the  Addition  of  Citrate  oi 
Soda  to  Cow's  Milk  in  Infant  Feeding '),  Lancet,  1904,  ii.  433. 
'■'  Munch.  Med.  Woch.,  1900,  xlvii.  1661. 
^  Meister,  Lucius,  and  Briining,  51,  St.  Mary  Axe,  E.C. 

*  '  Archives  of  Pediatrics,'  1889,  vi.  833,  and  '  Milk  Analysis  and  Infant  Feed- 
ing,' p.  74;  Philadelphia,  1885. 

*  Described  by  Cautley,  '  Infant  Feeding,'  p.  150. 


456  FOOD  AND  DIETETICS 

Proteia         i-a 

Fat 4-2 

Sugar 6-5 

It  is  rather  too  rich  in  fat  for  general  use. 

Biedert^  uses  a  mixture  of  130  c.c.  of  cream  (10  per  cent,  fat) 
with  390  of  water  and  18  grammes  of  milk-sugar.  This  results  in  a 
milk  containing  i  per  cent,  of  casein,  2^  per  cent,  of  fat,  and  5  per 
cent,  of  sugar.  For  very  young  infants  the  mixture  may  have  to 
be  given  more  diluted. 

3.  SoxJilet^  dilutes  the  milk  with  half  its  volume  of  a  I2|  per  cent, 
solution  of  milk-sugar.  This  makes  the  proportion  of  protein  the  same 
as  in  human  milk,  but  leaves  the  fat  one-third  less  and  the  sugar 
one-half  more.  In  other  words,  some  of  the  fat  by  this  method  is 
replaced  by  sugar.  Considering  the  great  importance  of  fat  in  the 
infant  economy,  it  is  doubtful  if  such  a  substitution  is  justifiable. 
Heubner,^  however,  reports  that  he  has  fed  thousands  of  the  most 
miserable  infants  on  the  mixture  with  the  greatest  success.  It 
certainly  has  the  merit  of  simplicity. 

4.  So-called  humanized  milks  are  now  prepared  on  a  large  scale  by 
many  dairy  companies.  By  diluting  the  milk  with  an  equal  quantity 
of  water  and  subjecting  it  to  the  action  of  a  centrifuge,  it  is  divided 
into  two  equal  parts,  one  of  which  contains  practically  all  the  fat  of 
the  original  milk  but  only  half  of  the  other  ingredients.  The 
deficiency  of  sugar  is  remedied  by  the  subsequent  addition  of  that 
constituent  in  the  necessary  proportion.  The  proportion  of  protein 
in  such  a  milk  will  tend  to  be  somewhat  too  low,  and  the  mineral 
matter  still  too  high,  but  otherwise  the  composition  will  correspond 
pretty  closely  to  that  of  human  milk. 

The  following  analyses  of  their  humanized  milks  are  supplied  by 
the  Aylesbury  Dairy  Company  : 

No.  I.  No.  2.  (diluted).  '^«'««»  ^^'^*- 

Water     ..         ..     89-43  88-3  88-44                87-6 

Protein  ..         ..       i'3                    22  1-49                  i"5 

Fat          ..         ..       40                    3-6  359                  3-5 

Sugar     ..         ..       4-7                    5*2  628                  6'3  . 

Mineral  matter. .       049                  0*57  0*20                  0*27 

Paget's  Perfected  Milk  Food^  is  a  concentrated  humanized  milk. 
When  diluted  with  2  parts  of  water  it  yields  a  fluid  of  the  following 
composition : 

1  See  Reinach,  Mi'inch.  Med.  Woch.,  1899,  xlvi.  956. 

«  Mihich.  Med.  Woch.,  1893,  xl.  61. 

'  Heubner,  Berlin.  Klin.  Woch.,  1894,  xxxi.  841. 

*  Clay,  Paget,  and  Co.,  Limited,  Ebury  Street,  S.W. 


HUMANIZED  MILKS  457 

Water           8804 

Protein         ,,         ..         ..  i  08 

Fat 383 

Sugar            6-82 

Mineral  matter       ..         ..  023 

It  is  sterile  and  keeps  indefinitely.  My  own  examination  of  it 
shows  that  it  is  certainly  rich  in  fat,  and  hardly  clots  at  all  with 
rennet.     It  is,  perhaps,  somewhat  deficient  in  protein. 

Gaertner's  Fettmilch^  is  another  commercial  humanized  milk 
prepared  on  the  above  principles.  It  is  stated  to  have  the  following 
proportions  of  the  chief  ingredients : 

Protein         1-5  per  cent. 

Fat    ..         ..         ..         ,,  32        ,, 

Sugar  60        ,, 

Mineral  matter       ..         ..  035      ,, 

With  the  exception  of  a  somewhat  higher  proportion  of  mineral 
constituents  (a  point  of  no  importance),  these  figures  are  almost 
identical  with  those  yielded  by  an  average  sample  of  human  milk. 
Very  good  results  from  its  use  have  been  reported  by  several 
observers, 2  although  others  have  put  on  record  cases  in  which  it 
has  disagreed.' 

One  defect  common  to  all  the  above  methods  must  be  pointed 
out.  It  is  true  that  they  bring  the  total  amount  of  protein  down 
more  or  less  equal  to  that  found  in  human  milk.  They  do  not, 
however,  influence  in  any  way  the  relative  proportion  of  the  two 
kinds  of  protein — casein  and  albumin.  In  all  of  them  the  former 
remains  relatively  higher  than  in  human  milk,  and  the  latter  rela- 
tively lower.  For  this  reason  the  resulting  mixtures  must  remain 
more  difficult  of  digestion  than  human  milk.  Various  methods  of 
getting  over  this  difficulty  have  been  proposed. 

Hammarsten^  takes  advantage  of  the  fact  that  whey  contains  the 

albumin  of  the  milk  but  not  its  casein  (see  p.  132),  and  by  making 

a  mixture  in  the  following  proportions  : 

Cream        . .         , .         . .     200  parts. 
Whey         ,,         ,,         ,.     800      ,, 

or 

Cream       ..         ,.         ..     100  parts, 
Milk  ..         ..         ..     100      ,, 

V.'hey         ..         ..  ..     800      ,, 

he  gets  a  fluid  which  contains  albumin  and  casein  in  the  same  pro- 
portion as  in  human  milk. 

1  Sold  by  the  Friern  Manor  Dairy  Company. 

^  See  Gaertner,  Wiener  Med.  Woih.,  1896,  xlvi.  1004;  Fischer  and  Poole,  New 
York  Medical  Record,  1897,  lii.  839  ;  and  Schiitz,  Wiener  Klin.  Woch.,  1S96,  ix.  ni6 
(experiments  on  adults). 

*  Hauser's  resume,  Fortsch.  d.  Med.,  1897,  xv.  929.  See  also  Monti,  Wiener 
Klinik,  1897,  xxiii.,  Hft.  i,  2,  and  3  ;  and  the  Year-Book  of  Treatment,  1897,  p.  159. 

*  Jahres-Ber.  /.  Thierchemie,  p.  206,  1895. 


458  FOOD  AND  DIETETICS 

Ashhy^  was  also  a  strong  believer  in  the  virtues  of  whey.  He 
prepared  it  by  placing  30  ounces  of  fresh  milk  in  a  Hawksley's 
sterilizer  and  heating  to  104°  F. ;  two  teaspoonfuls  of  Benger's 
essence  of  rennet  are  added,  and  the  bottle  set  aside  for  a  few 
minutes.  When  curdling  has  taken  place  the  curd  is  thoroughly 
broken  up  by  stirring  and  shaking,  and  the  whey  is  then  strained 
off  through  fine  muslin.  In  this  way  22  or  23  ounces  of  opalescent 
whey  are  obtained.  This  is  heated  to  180"  for  twenty  minutes  to 
destroy  the  rennin,  and  is  then  strained  again.  The  composition  of 
the  whey  so  obtained  is  as  follows : 

Protein 0*97  I  Salts  0"6l 

Fat 20     1 

The  whey  may  be  used  alone  with  the  sole  addition  of  2  or  3 

drachms  of  milk-sugar  to  the  pint  as  a  food  for  newly-born  infants. 

A  weak  '  humanized'  milk  may  be  prepared  by  mixing  10  ounces 

of  fresh  milk  with  20  of  whey  and  adding  \  ounce  of  milk-sugar. 

It  has  the  following  composition : 

Protein I75  I   Sugar  6*0 

Fat..  2-5     I   Salts o'6 

If  a  milk  richer  in  fat  is  desired,  '  top '  milk  should  be  used  in  the 
same  proportion.  To  prepare  it,  let  a  quart  of  fresh  milk  stand  in 
a  covered  jar  in  a  cold  place  for  four  or  five  hours,  remove  the  upper 
10  ounces  by  skimming,  and  add  to  this  20  ounces  of  sterilized  whey 
and  I  ounce  of  milk-sugar.  The  mixture  should  contain  4  per  cent, 
of  fat.  A  grain  or  two  of  bicarbonate  of  soda  may  be  added  to  the 
mixtures  to  render  them  alkaline. 

Monti^  also  recommends  the  use  of  whey.  For  the  first  three 
months  he  employs  a  mixture  of  equal  parts  of  milk  and  whey,  after 
that  a  mixture  of  two  of  milk  to  one  of  whey. 

Vigier^  divides  the  milk  into  two  equal  parts.  He  skims  one  and 
adds  the  cream  to  the  other.  The  former  is  then  clotted  with  rennet, 
and  the  whey  added  to  the  other  half.  The  resulting  mixture  has 
the  following  composition : 

Protein 2-36  I   Fat 375 

Sugar         4-10  I  Salts  075 

Winter*'  goes  on  a  similar  plan  when  he  divides  the  milk  into  two 
parts,  skims  one,  and  adds  the  cream  to  the  other.  He  then 
coagulates  the  skimmed  portion  with  rennet,  and  adds  the  whey 

1  Edinburgh  Medical  Journal,  1899.  N.S.,  v.  389. 

•  Wiener  Klinik,  1897,  xxiii.,  Hft.  i,  2,  and  3. 

»  Quoted  by  Monti. 

«  Quoted  by  Rothschild,  '  L'Allaitement  Mixta,'  etc.,  Paris,  189S. 


PERCENTAGE  FEEDING  459 

60  obtained  to  the  first  part.  Such  a  mixture  contains  the  casein 
and  albumin  in  proper  proportions,  but  is  still  apt  to  be  deficient 
in  fat. 

The  advantage  of  whey  as  a  diluent  is  that  it  is  antiscorbutic,  and 
contains  albumin  and  a  little  fat.  It  must  be  admitted,  however, 
that  the  preparation  of  the  above  mixtures  demands  more  time  and 
trouble  on  the  part  of  the  mother  or  nurse  than  one  can  usually 
count  on. 

Lehmann'^  dilutes  the  milk  till  the  casein  is  in  proper  proportion, 
and  then  adds  sugar  and  cream.  In  order  to  bring  up  the  proportion 
of  albumin,  he  takes  the  white  of  an  egg,  mixes  it  with  four  table- 
spoonfuls  of  water,  and  adds  one-third  of  the  mixture  to  the  milk. 

Backhaus^  removes  part  of  the  casein  and  peptonizes  the  rest 
of  it  by  the  addition  of  a  combination  of  rennin,  trypsin,  and  bi- 
carbonate of  soda.  Cream  and  lactose  are  then  added  to  the  whey. 
The  resulting  mixture  is  known  commercially  as  Nutricia,'  and  has  a 
composition  almost  identical  with  that  of  human  milk — viz.,  protein 
1*38,  fat  3"2o,  sugar  6*50,  mineral  matter  0*42.*  It  has  given  excel- 
lent results  in  infant  feeding. 

The  albumin  of  milk  can  now  be  obtained  in  a  soluble  form — 
Albulactin — and  may  be  used  instead  of  white  of  egg  to  enrich 
cream  mixtures  in  protein  or  added  to  diluted  milk.  It  prevents  the 
formation  of  a  dense  clot  of  casein.*' 

In  America  the  modification  of  cow's  milk  to  suit  the  requirements 
of  infancy  has  been  reduced  to  an  exact  science.  This  has  been 
chiefly  brought  about  by  the  work  of  Rotch.  Milk  containing  a 
known  proportion  of  casein  is  prepared  by  adding  to  it  standard 
solutions  of  cream  and  milk-sugar  in  different  proportions.  A 
mixture  can  be  prepared  of  any  desired  composition.  Laboratories 
have  been  established*  in  all  the  principal  towns  of  the  United 
States  in  which,  on  the  receipt  of  a  physician's  formula,  a  milk 
containing  the  exact  proportion  of  each  ingredient  which  the 
digestive  peculiarities  of  any  given  infant  may  necessitate  can  be 
dispensed  as  accurately  as  a  chemist  compounds  a  prescription.' 
Useful  and  desirable  as  this  is  in  the  case  of  badly  nourished  or 

'  Archiv  f.  d.  Ges.  Phys.,  1894,  hi.  558.         *  J  our  n.  fur  Landwithscha/t,  1896. 

*  A.  Stiebler,  7,  Eastcheap,  E.G.  *  Lancet  Analysis,  1908,  ii.  1153. 

*  See  Alexander  and  BuMowa.,  Journ.  Amer.  Med.  Assoc,  1910,  Iv.  1196. 

*  Walker- Gordon  Laboratories.  One  of  these  is  now  open  in  London 
(54,  Weymouth  Street,  W.). 

"  Wentworth,  however,  has  shown  that  the  mixture  as  dispensed  does  not 
always  exactly  conform  with  the  formula  ordered  ('The  Importance  of  Milk 
Analysis  in  Infant  Feeding,'  Boston  Med.  and  Surg.  Journ.,  1902,  cxlvi.  683; 
ibid  ,  1902,  cxlvii  5). 


46o  FOOD  AND  DIETETICS 

dyspeptic  babies,  it  is  an  unnecessary  refinement  in  the  artificial 
feeding  of  healthy  infants. 

There  is  still  one  point  in  which  any  of  the  above  modifications  of 
cow's  milk  is  lacking.  Human  milk  as  it  leaves  the  breast  is 
practically  a  sterile  fluid  ;  but  this  is  by  no  means  true  of  cow's  milk 
as  it  reaches  the  consumer.  It  contains,  as  we  have  already  seen 
(Chapter  VII.),  not  only  the  organisms  which  cause  milk  to  become 
sour,  but  also,  and  not  infrequently,  the  germs  of  actual  disease.  These 
are  specially  dangerous  to  infants,  because  the  low  degree  of  acidity 
which  is  characteristic  of  the  contents  of  the  infant  stomach  enables 
these  germs  to  pass  on  almost  uninjured  into  the  intestine,  where  they 
may  readily  become  the  seeds  of  disease.  For  this  reason,  then,  the 
destruction  of  the  germs  in  cow's  milk  is  of  the  first  importance 
in  preparing  it  as  an  infant  food.  The  methods  by  which  this  may 
be  done  have  been  already  considered  (Chapter  VII.),  but  it  may 
be  repeated  here  that  in  most  cases  simple  boihng  is  sufficient. 
•  Pasteurization '  of  the  mixture  at  a  temperature  of  70°  C.  will 
almost  certainly  ensure  the  destruction  of  the  disease  germs,*  but  if 
the  milk  has  to  be  preserved  for  any  length  of  time  '  sterilization ' 
should  be  carried  out.  We  have  already  seen  that  the  digestibility 
and  absorption  of  the  milk  are  not  interfered  with  by  such  a  process 
to  any  important  extent.' 

Reviewing  the  whole  question  of  the  modification  of  cow's  milk,  it 
may  be  said  that  the  first  method  described  (boiling,  with  subsequent 
dilution  and  addition  of  cream  and  sugar)  is  the  best  and  simplest 
method  for  domestic  use.  If,  however,  expense  is  no  objection,  the 
use  of  such  a  commercial  preparation  as  Fettmilch  is  equally  good 
and  less  troublesome.  The  correction  of  the  relative  proportions  of 
casein  and  albumin,  although  theoretically  sound,  is  practically  not 
a  necessity  in  the  case  of  healthy  infants. 

When  all  is  said  and  done,  however,  cow's  milk,  no  matter  how 
skilfully  modified,  is  much  inferior  to  human  milk  as  a  means  of 
feeding  infants,  this  probably  depending  on  those  qualitative 
difi"erences  in  the  composition  of  the  two  fluids  which  no  method  of 
modification  can  entirely  overcome. 

1  It  has  not  been  conclusively  proved  capable  of  destroying  the  tubercle 
bacillus. 

2  The  only  disadvantage  attending  the  use  of  boiled  or  sterilized  milk  seems 
to  be  that  it  is  occasionally  the  cause  of  infantile  scurvy,  otherwise  all  the 
advantages  are  on  the  side  of  boiling  (see  '  Report  to  the  Local  Government 
Board  upon  the  Available  Data  in  Regard  to  the  Value  of  Boiled  Milk  as  a  Food 
for  Infants  and  Young  Animals,'  by  Dr.  Janet  Lane  Clayton,  1912). 


[46i  ] 


CHAPTER  XXVI 

THE  PRINCIPLES  OF  FEEDING  IN  INFANCY  AND  CHILD- 
HOOD (continued):  OTHER  SUBSTITUTES  FOR  HUMAN  MILK 
(PEPTONIZED  MILK,  CONDENSED  MILK,  DESICCATED 
MILK,  PROPRIETARY  FOODS);  FEEDING  OF  OLDER 
CHILDREN 

I.  Partially  Peptonized  Milk. 

It  is  believed  by  some  authorities  that  one  of  the  essential  differences 
between  the  casein  of  human  milk  and  that  of  the  milk  of  the  cow 
is  that  the  former  is  really  a  stage  nearer  the  digested  condition 
(i.e.,  peptone)  than  the  latter,  and  that  the  greater  digestibility  of 
human  casein  is  due  to  that  fact.  Whether  this  be  so  or  not,  there 
can  be  no  doubt  that  even  the  partial  peptonization  of  cow's  milk 
renders  it  much  more  easy  of  digestion.  Of  complete  peptonization 
there  is  no  need  to  speak  here.  It  is  of  the  greatest  utility  as  a 
temporary  expedient  in  some  cases  of  disease,  or  in  feeble  and 
exhausted  babies,  but  is  not  really  required  for  healthy  infants. 
Sooner  or  later  the  stomach  must  be  educated  up  to  dealing  with 
pure  cow's  milk,  and  the  sooner  the  education  is  begun  the  better. 
Partial  peptonization,  however,  may  often  be  had  recourse  to  with 
advantage  as  the  first  stage  in  this  process  of  education  in  the  case 
of  infants  whose  stomachs  have  a  greater  difficulty  than  usual  in 
dealing  with  cow's  casein.  It  can  be  conveniently  carried  out  by 
means  of  FairchiWs  Peptogenic  Milk-powder.  Each  measure  of  the 
powder  contains  the  ferment  required  to  digest  a  certain  quantity  of 
milk,  along  with  some  bicarbonate  of  soda,  which  renders  the  milk 
slightly  alkaline,  and  enough  milk-sugar  to  raise  that  ingredient  to 
the  proportion  found  in  mother's  milk. 

By  following  the  directions  supplied  with  the  powder,*  the  process 

*  In  preparing  the  milk  for  an  infant  with  a  very  delicate  digestion,  it  is 
advisable  not  to  add  so  much  cream  as  is  recommended  in  the  directions.  The 
relative  proportions  of  milk  and  water  and  the  duration  of  peptonization  can  also 
be  varied  to  suit  different  cases. 


463  FOOD  AND  DIETETICS 

of  digestion  is  only  carried  so  far  as  partially  to  change  the  casein 
of  the  milk,  sufficient  to  prevent  its  clotting,  but  not  enough  to 
absolve  the  stomach  from  all  further  labour.  Thus,  digestion  is 
rendered  easy  without  the  stomach  being  demoralized.  The  use  of 
this  method  is  strongly  recommended  by  Professor  Chittenden.^ 
He  analyzed  the  resulting  mixture,  and  compares  it  with  human 
milk  as  follows : 


Specific  gravity 
Water 
Protein 
Fat  ,. 

Sugar 
Mineral  matter 
Total  solids 
Reaction 


Human  Milk. 

Milk  preparei  by 

Ptptogenii  Mtlh-powder, 

103 1 

1032 

867 

860 

20" 

2  09 

41 

438 

69 

726 

02 

026 

13-2 

13-9 

Alkaline. 

Alkaline. 

It  will  be  observed  that  the  two  fluids  are  almost  identical  m 
composition.  I  find,  too,  that  milk  prepared  by  this  method  does 
not  clot  with  rennet,  even  in  the  presence  of  a  considerable  amount 
of  acid. 

2.  Condensed  Milk. 

The  importance  of  studying  condensed  milk  will  be  realized  when 
it  is  learnt  that  nearly  1,000,000  cwt.  of  it  are  imported  into  this 
country  every  year,  and  there  is  no  commoner  substitute  for  human 
milk,  especially  amongst  the  poorer  classes,  than  this. 

(fl)  Chemical  Composition. — Condensed  milk  is  simply  cow's  milk 
from  which  a  large  proportion  of  the  water  has  been  removed.  The 
removal  is  effected  by  evaporation  under  reduced  pressure  and  with 
the  aid  of  a  greater  or  less  degree  of  heat.  As  a  rule,  the  milk  is  only 
reduced  to  one-third  of  its  original  volume,  so  that  in  order  to  restore 
it  again  to  the  condition  of  the  original  milk  all  that  is  necessary  is  to 
add  to  it  t\vice  its  volume  of  water.  Unfortunately,  however,  the 
milk  used  for  condensation  is  not  always  pure  milk.  Very  often  the 
cream  has  been  removed  from  it  by  a  separator,  so  tbat  the  product 
is  really  condensed  skim  milk.  Cane-sugar  is  also  f  equently  added 
to  the  milk  after  condensation,  in  order  to  aid  in  .ts  preservation. 
As  a  matter  of  fact,  all  the  condensed  skim  milks  found  in  the  market 
have  also  been  sweetened,  so  that  one  may  divide  condensed  milks 
into  the  following  groups : 


1  New  York  Medical  Jouyml,  1896,  Ixiv.  71. 

8  The  proportion  of  protein  here  given  is  probably  too  high. 


CONDENSED  MILKS  463 

1.  Unsweetened  and  condensed  whole  milk. 

2.  Sweetened^  and  condensed  whole  milk. 

3.  Sweetened  and  condensed  skim  milk. 

I.  Of  the  unsweetejied  condensed  whole  milks  there  are  four  examples, 
which  have  the  following  composition 2; 


Brand. 

Total  Solids. 

Protein. 

Fat. 

Milk-sugar. 

Ideal 

380 

8-3 

124 

160 

First  Swiss 

367 

97 

105 

14-2 

Viking 

342 

90 

100 

133 

HoUandia  . . 

430 

II-3 

9-8 

185 

If  I  part  of  such  a  milk  is  diluted  with  2  parts  of  water,  the 
resulting  fluid  corresponds  more  or  less  closely  to  a  good  sample  of 
pure  cow's  milk. 

One  disadvantage  of  the  unsweetened  milks  is  that  they  are  apt  to 
go  bad  when  the  tin  has  been  opened.  For  this  reason  they  should 
be  kept  in  a  cold  place.  It  would  be  an  advantage  also  if  the  manu- 
facturers would  put  up  such  milk  in  small  tins,  one  of  which  would 
be  sufficient  for  a  day's  supply. 

2.  The  sweetened  condensed  whole  milks  contain,  as  a  rule,  rather 
more  added  cane-sugar  than  there  are  solids  in  the  milk.  The 
following  is  the  composition  of  some  of  the  best  brands ;  they  are 
arranged,  again,  according  to  their  richness  in  fat : 


Brand. 

Total  Solids. 

Protein. 

Fat. 

Milk-sugar. 

Cane-sugar. 

Nestle    .. 

..       772 

97 

137 

150 

372 

Rose 

..       766 

8-3 

124 

17  6 

361 

Milkmaid 

..       763 

97 

no 

14-6 

387 

Full  Weight 

..       765 

123 

no 

135 

372 

Anglo- Swiss 

..       744 

8-8 

IO-8 

160 

371 

There  are  many  other  brands  in  the  market  besides  these,  but  none 
of  them  is  superior  to  the  above. 

Now,  although  the  members  of  this  group  contain  as  much  fat  as 
the  unsweetened  condensed  milks,  yet  so  much  sugar  has  been 
added  that  if  they  are  mixed  with  only  as  much  water  as  has  been 
removed  in  condensation,  the  resulting  fluid  would  be  so  sweet  that 
one  could  hardly  drink  it.  Hence,  a  degree  of  dilution  is  recom- 
mended on  the  tins  of  these  brands  which  renders  it  impossible  for 
the  resulting  fluid  to  be  at  all  like  cow's  milk  in  its  proportion  of 
protein  and  fat. 

3.  Of  the  condensed  separated  [or  skim)  milks  there  are  an  immense 

1  The  milk  may  be  either  fully  sweetened  by  the  addition  of  35  to  40  per 
cent,  of  cane-sugar,  or  partially  sweetened  by  the  addition  of  smaller  quantities 
up  to  18  per  cent. 

8  The  analyses  of  condensed  milks  in  this  chapter  are  taken  from  Pearmain 
and  Moor's  '  Analysis  of  Food  and  Drugs,'  part  i.,  pp.  69-78. 


4-64 


FOOD  AND  DIETETICS 


number  in  the  shops.  They  resemble  in  composition  the  second 
group  just  described,  except  in  that  they  contain  almost  no  fat 
(always  less  than  2  per  cent.).  When  diluted  in  the  proportions 
recommended  for  infants,  the  resulting  fluid  is  very  poor  in  protein 
and  almost  free  from  fat,  and  is  therefore  entirely  unsuited  for  a  baby's 
nourishment. 

It  should  be  noted  that  the  composition  of  all  forms  of  con- 
densed milk  varies  considerably,  owing  to  differences  in  richness 
of  the  original  milk,  and  to  variations  in  the  degree  of  condensa- 
tion and  in  the  amount  of  sugar  which  has  been  added.  This  is 
borne  out  by  the  following  table  taken  from  a  Report  by  Dr. 
Coutts  to  the  Local  Government  Board, ^  which  is  based  upon  a 
large  number  of  analyses  taken  from  various  sources : 

VARIATIONS  IN  CHEMICAL  COMPOSITION  OF  CERTAIN 
CLASSES  OF  CONDENSED  MILK. 


Full  Cream. 

Machine -sk  imnted 

Sweetened, 

Sweetened. 

Unsweetened, 

Lowest. 

Highest. 

Lowest. 

Highest. 

Lowest. 

Highest. 

Total  solids  per  cent.  . . 

68-1 

83-6 

29-2 

38-0 

56-9 

79-1 

Fat                      „ 

8-0 

137 

8-2 

ii-g 

o*i 

6-5 

Protein               „ 

7 '3 

11-4 

80 

10 -o 

7-6 

12-3 

Ash                      „ 

1-6 

3*4 

1-6 

2-5 

1-6 

2-9 

Lactose               „ 

II-6 

17-6 

ii-i 

i6-o 

10-9 

17-0 

Cane-sugar         „ 

36-1 

44 '6 

Nil 

Nil 

30*4 

52-6 

{b)  Digestibility  of  Condensed  Milk.  —  It  must  be  admitted  that 
condensed  milk  is  more  easily  digested  than  fresh  cow's  milk. 
When  diluted  in  such  proportion  as  to  restore  them  to  the  con- 
dition of  ordinary  cow's  milk,  the  condensed  milks  either  do  not 
clot  with  rennet  at  all,  or  the  resulting  curd  is  much  looser  than 
in  the  case  of  pure  cow's  milk.^  The  presence  of  acid  does  not 
affect  the  result.     The  explanation  of  these  facts  probably  is  that 


*  *  An  Inquiry  as  to  Condensed  Milks,  with  Special  Reference  to  their  Use  as 
I'afants'  Foods,'  191 1. 

*  The  experiments  were  performed   with   the  First  Swiss   brand   and   with 
Nestle's. 


CONDENSED  MILKS  465 

the  casein  undergoes  some  chemical  change  in  the  process  of 
condensation  which  renders  it  unfitted  to  form  a  dense  clot. 
Certainly  this  greater  digestibility  is  one  point  in  favour  of  con- 
densed milk,  and  justifies  its  occasional  use  for  infants  who  are 
entirely  unable  to  digest  ordinary  cow's  milk,  even  when  specially 
modified.^ 

(c)  Nutritive  Value  and  Economy  of  Condensed  Milk. — The  chief  defect 
of  condensed  milks  from  a  nutritive  point  of  \aew  is  that  they  are 
apt  to  contain  too  little  fat.  The  unsweetened  milks  are  alone  satis- 
factory in  this  respect.  The  skim  milks  are  absolutely  to  be  con- 
demned on  that  account,  and  even  the  sweetened  whole  milks,  though 
they  contain  all  the  fat  of  the  original  milk,  yet  require  so  great  a 
degree  of  dilution,  owing  to  the  amount  of  sugar  which  they  contain, 
that  the  product  is  notably  deficient  in  fat.  '  The  following  table 
shows  the  character  of  the  liquid — it  cannot  be  called  milk — that  is 
produced  by  following  out  the  directions  on  the  labels  of  half  a  dozen 
of  the  best  brands  of  (sweetened)  whole-cream  milk '  (Pearmain  and 
Moor) : 


Sweetened 
Whole  Milh. 

Dilution  recommended 

for  Household 

Purposes. 

Fat  in  such 
Product. 

Dilution 

recommended  for 

Infants'  Use. 

Fat  in  such 

Product. 

A 

I  to  3 

26  per  cent. 

I  to  5 

1-8  percent 

B 

I  ..  5 

16 

I  ..  14 

07 

C 

I  ..  5 

1-6 

I  ..  14 

06 

D 

I  ..  6 

14 

I  ..  15 

07 

E 

I  ..  5 

2*1 

I  .,  14 

0-8 

F 

I  ..  5 

17 

I  ..  14 

07 

G 

I  ..  5 

17 

I  ..  14 

07 

Human  milk 

— 

35 

There  can  be  no  doubt  that  an  immense  amount  of  harm  is  done  to 
infants  by  the  indiscriminate  use  of  such  milks.  Babies  fed  on  them 
may  look  fat  enough,  but  they  are  pale  and  flabby,  and  often  suffer 
from  rickets,  for  fatness  produced  by  abundance  of  sugar  in  the  milk 
is,  as  has  been  already  pointed  out,  by  no  means  a  sure  indication 
of  health,  and  the  pictures  of  such  fat  but  flabby  infants  so  freely 
spread  abroad  by  the  makers  of  condensed  milks  are  very  de- 
ceptive. 

If  a  sweetened  condensed  milk  is  used  at  all,  it  should  only  be 
for  a  short  period  (not  beyond  the  first  three  or  four  months), 
and  the  deficiency  of  fat  should  be  made  good  by  the  addition 
to  the  diet  of  cream  or  cod-liver  oil.  Babies  of  delicate  diges- 
tion often  do  well  for  a  time  on  Nestle's  milk  in  the  proportion 
of  one  teaspoonful  to  six  tablespoonfuls  of  water.     Such  a  mixture 

*  The  great  degree  of  dilution  in  which  condensed  milk  is  usually  given  no 
doubt  also  explains  in  part  the  ease  with  which  babies  digest  it. 

30 


466  FOOD  AND  DIETETICS 

contains  113  per  cent,  of  protein,  1-28  per  cent,  of  fat,  and  672  per 
cent,  of  sugar,  and  by  the  addition  of  one  teaspoonful  of  centrifugal 
cream  to  each  feed  the  fat  is  brought  up  to  3  per  cent.  The  casein 
in  this  mixture,  being  very  dilute,  is  easily  digested,  and  the  relative 
excess  of  sugar  does  no  harm  if  such  a  method  of  feeding  is  not 
continued  beyond  the  fourth  month. 

The  only  kind  of  condensed  milk  which  can  be  unreservedly 
recommended,  however,  is  that  made  from  whole  cow's  milk  with- 
out the  addition  of  sugar.  If  i  part  of  such  a  preparation  is 
diluted  with  2  parts  of  water,  the  product  may  be  regarded  as 
identical  with  good  cow's  milk,  and  will  therefore  require  further 
dilution,  sweetening,  and  addition  of  cream,  just  as  fresh  milk  does 
(P  454)-  Used  in  this  way  condensed  milk  is  convenient  in  cases  in 
which  fresh  milk  is  for  any  reason  unobtainable,  or  for  temporary 
use  in  the  case  of  infants  who  are  unable  to  digest  the  latter.  There 
is,  however,  one  disadvantage  in  its  use  which  has  yet  to  be  men- 
tioned. It  has  been  found  that  infants  fed  exclusively  on  tinned 
foods  are  apt  to  suffer  from  a  peculiar  disease  of  the  blood  and  bones 
which  resembles  scurvy.  Infants  fed  on  fresh  milk  never  suffer  in 
this  way,  for  fresh  milk  contains  some  'antiscorbutic'  element  which 
has  not  yet  been  identified.  In  order  to  counteract  the  tendency  to 
this  disease,  it  is  well  to  give  infants  which  are  reared  on  condensed 
milk    a   little   orange   or   grape   juice   two    or   three    times   every 

week. 

The  question  whether  condensed  milks  are  to  be  regarded  as 
sterile  or  not  is  one  of  some  importance.  It  seems  to  be  by  no 
means  certain  that  they  are,  for  the  degree  of  heat  to  which  they 
are  subjected  during  condensation  is  not  necessarily  sufficient  to  kill 
all  disease  germs.^ 

As  regards  the  question  of  economy,  there  is  nothing  to  be  said 
in  favour  of  condensed  milks.  The  cost  of  manufacture  is  bound 
to  add  considerably  to  that  of  the  original  milk,  and,  as  a  matter  of 
fact,  their  cost  is  equivalent  to  that  of  cow's  milk  at  nearly  4d. 
per  pint.2  In  other  words,  the  removal  of  two-thirds  of  the  water 
from  the  milk  has  about  doubled  its  cost. 

'  See  '  Report  to  the  Local  Government  Board  upon  the  Effects  of  Certain 
Condensing  and  Drying  Processes  used  in  the  Preservation  of  Milk  upon  KS 
Bacterial  Contents.'  by  Dr.  S.  Delepine  (Food  Reports  No.  21),  iQM- 

2  A  tin  of  condensed  milk  contains  about  290  c.c.  This,  diluted  with  2  parts 
of  water  =  870  ex.,  or  about  i^  pints  of  cow's  milk,  and  the  origina.  tin 
costs  5id, 


CONDENSED  MILKS  467 


3.  Desiccated  Milk. 

Desiccated  milk,  the  general  characters  of  which  have  already 
been  described  (p.  119),  is  now  being  largely  used  in  infant  feeding. 
It  has  the  advantage  of  being  convenient,  comparatively  sterile, 
and  easily  digested,  and  there  seems  to  be  no  reason  to  fear  that  it 
predisposes  either  to  rickets  or  scurvy.  A  full-cream  dried  milk 
should  contain  about  26  per  cent,  of  fat,  and  if  dissolved  in  the 
proportion  of  one  part  to  eight  of  water,  ordinary  milk  is  recon- 
stituted. In  order  to  prepare  a  solution  more  nearly  resembling 
human  milk,  two  tablespoon fuls  of  the  dried  milk  and  six  tea- 
spoonfuls  of  sugar  may  be  dissolved  in  a  pint  of  water.  As  regards 
total  protein  and  sugar,  such  a  solution  is  approximately  correct, 
but  it  is  deficient  in  fat,  which  must  either  be  added  in  the  form  of 
cream  (i  ounce  of  46  per  cent,  cream),  or  given  in  some  other 
shape — for  example,  cod-liver  oil.  The  proprietary  food  Glaxo 
consists  of  dried  milk,  lactose,  and  cream,  in  such  proportions  that 
when  suitably  dissolved  the  solution  approximates  to  human  milk 
in  quantitative  composition. 


4.  Proprietary  Foods  for  Infants. 

There  is  an  immense  number  of  patent  infant  foods,  almost  every 
one  of  which  claims  to  be  *  the  best  food  for  infants '  or  '  a  perfect 
substitute  for  mother's  milk.'  These  claims  are  devoid,  of  course, 
of  all  scientific  justification,  for,  as  regards  the  former,  no  one  will 
deny  that  the  best  food  for  infants  is  human  milk,  and  as  regards 
the  latter,  it  has  already  been  shown  that  cow's  milk  can  never  be  so 
modified  as  to  resemble  human  milk  in  its  qualitative  composition. 
Further,  the  ingredients  of  any  patent  food  for  infants  require  to 
be  carefully  scrutinized,  for  many  of  them  contain  unaltered  starch, 
and  starch  is  not  a  substance  which  can  be  given  with  impunity  to 
all  infants,  even  although  some  of  them  are  able  to  digest  a  little  of 
it  without  harm.  Many  of  them,  too,  are  lamentably  poor  in  fat, 
the  importance  of  which  as  a  constituent  of  an  infant's  diet  has 
already  been  fully  insisted  upon.  A  deficiency  in  protein  is  another 
common  fault  amongst  them,  and  this,  especially  if  combined  with 


468  FOOD  AND  DIETETICS 

poverty  in  fat,  may  explain  the  frequency  with  which  rickets  is 
observed  in  babies  reared  upon  such  foods.  As  there  is  a  con- 
siderable degree  of  discrepancy  in  the  published  analyses  of  these 
preparations,  I  have  submitted  the  majority  of  those  found  on  the 
English  market  to  a  fresh  examination,  and  the  results,  along  with 
a  brief  description  of  each  particular  food,  are  contained  in  the 
followinj;  table ; 


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INFANT  FOODS  469 

In  judging  of  the  value  of  these  numerous  preparations,  one  may 
divide  them  into  the  following  groups  : 

1 .  Foods  prepared  from  cow's  milk  with  various  additions  or  alterations, 
and  requiring  the  addition  of  water  only  to  he  ready  for  use.  This  group 
includes : 

*  AUenbury '  first  and  second  foods. 

Carnrick's  Soluble  Food. 

Horlick's  Malted  Milk. 

Milo  Food. 

Manhu  Infant  Food, 

Muffler's  Food. 

Glaxo. 

Comparing  these  preparations  with  the  composition  of  dried 
human  milk  (see  table),  one  observes  that  they  are  mostly 
deficient  in  fat  and  too  rich  in  carbohydrate.  In  some  of  them, 
also,  there  is  insoluble  carbohydrate  (starch)  present,  which  is  not 
suitable  for  infants.  The  composition  of  some  of  them  when  ready 
for  use  is  contained  in  the  following  table : 


Human 

A  lUnhury  Food, 
No.  1.8 

Milo  Food.' 

Malted 
Milk.* 

Glaxo. 

Water     ,. 

87-60 

88-30 

92-76 

92-40 

91  10 

Protein   ,, 

1-52 

156 

o-8i 

i'i5 

2  18 

Fat 

3-28 

303 

0  36 

060 

2-52 

Sugar 

650 

6-47 

3-80 

5-38 

368 

Mineral  matter. . 

0*27 

060 

013 

0-29 

0-52 

The  essential  constituent  of  all  these  foods  is  dried  milk,  to  which 
milk-sugar,  malted  flour,  etc.,  have  been  added.  The  casein  in  all 
of  them,  moreover,  is  easily  digested,  as  it  clots  loosely,  if  at  all, 
with  rennet.  They  are  therefore  often  well  borne  by  delicate 
infants,  but  their  poverty  in  fat  renders  them  unsuitable  for  prolonged 
use.  They  are  also  not  free  from  the  risk  of  producing  scur-vy, 
although  this  danger  need  not  be  feared  if  their  administration  be 
confined  to  the  first  three  months  of  life. 

2.  The  second  group  consists  of  farinaceous  foods  prepared  from 
cereals  [usually  wheat),  of  which  the  starch  has  been  partly  or  wholly  trans- 
foryned  into  soluble  substances  (dextrins  or  malt-sugar),  and  which  require 
the  addition  of  milk  to  fit  them  for  use.  The  group  may  be  sub- 
divided into  two  classes : 

1  Camerer  and  Soldner's  analysis. 
'  Analysis  by  the  author. 

*  Analyses  by  Chittenden  {New  York  Medicaljournal,  1896,  Ixiv.  17). 

*  Jbid. 

*  Analysis  by  Droop  Richmond. 


470  FOOD  AND  DIETETICS 

(a)  Those  in  which  the  starch  has  been  transformed  before 
reaching  the  consumer — e.g.,  Mellin's  Food. 

(b)  Those  which  contain  malt  or  pancreatic  ferment,  which  convert 
the  starch  when  the  food  is  mixed — e.g.,  Benger's  Food,  Savory  and 
Moore's  Food,  Moseley's  Food  and  others. 

When  one  compares  the  composition  of  these  foods  with  that  of 
dried  human  milk,  one  is  struck  again  by  their  great  deficiency  in 
fat.  They  are  also  defective  in  mineral  matter  and  protein.  If 
mixed  with  water  alone,  therefore,  these  foods  could  never  be  true 
substitutes  for  human  milk.  In  all  of  them,  however,  the  addition 
of  some  fresh  cow's  milk  is  recommended,  although  the  proportion 
is  often  very  small.  They  can  only  be  of  use  in  supplementing  the 
diet  of  infants  who  are  unable  to  digest  much  cow's  milk,  but  the 
only  elements  they  supply  are  carbohydrate  and,  to  a  less  extent, 
protein.  Their  addition  to  cow's  milk  seems  also  to  aid  the 
digestion  of  the  latter,  probably  by  acting  mechanically  on  the 
curd,  as  barley-water  does.  They  may  also  be  regarded  as  useful 
(though  costly)  additions  to  the  diet  of  the  infant  after  its  sixth 
month. 

As  regards  the  relative  merits  of  the  two  classes  into  which  the 
group  is  divided,  it  may  be  said  that  there  is  no  advantage  in  a  food 
in  which  the  conversion  of  the  starch  only  takes  place  during  the 
preparation  of  the  food  for  use.  On  the  other  hand,  the  disadvantages 
of  such  a  plan  are  obvious,  for  the  result  is  at  the  mercy  of  the  skill 
and  care  of  the  mixer,  and,  as  a  matter  of  fact,  the  conversion  of 
the  starch  in  many  of  the  second  class  is  by  no  means  complete, 
even  when  the  directions  are  carefully  followed  (see  last  column  of 
table). 

It  is  undoubtedly  better  to  use  a  food  such  as  Mellin's,  in  which 
the  conversion  of  the  starch  has  been  completely  carried  out  in  the 
process  of  manufacture.  The  composition  of  Mellin's  Food,  when 
mixed  and  ready  for  use,  is  as  follows : 


Water 
Protein 
Fat    .. 

Carbohydrate 
Mineral  matter 


Human  Milk.^ 

Mellin's  Food.* 

8760 

88  GO 

152 

262 

328 

289 

650 

598 

027 

047 

1  Analysis  by  Camerer  and  Soldner. 

•  Analysis  by  Chittenden  {New  York  Medical  Journal,  1896,  Ixiv.  71). 


INFANT  FEEDING  471 

3.  The  third  group  includes  farinaceous  foods  in  which  the  starch 
has  not  been  predigested.  It  includes  such  foods  as  Ridge's, 
Neave's,  Frame  Food  Diet,  Chapman's  Whole  Wheat  Flour, 
Robinson's  Patent  Barley  and  Groats,  and  others.  These  pre- 
parations are  open  to  the  same  objections  as  those  in  the  second 
group,  with  the  additional  disadvantage  that  they  contain  much 
starch  which  has  either  not  been  acted  on  at  all  or  only  rendered 
slightly  more  digestible  by  the  process  of  baking  to  which  most  of 
them  are  subjected  in  the  course  of  manufacture.  Now,  into  the 
question  to  what  extent  infants  are  able  to  digest  unaltered  starch 
we  need  not  enter  here.  One  may  admit  that  recent  observations 
have  shown^  that  even  quite  young  infants  are  able  to  digest  much 
more  starch  than  was  formerly  believed.  The  practical  fact,  how- 
ever, remains,  that  starch  forms  no  part  of  the  diet  of  a  naturally- 
fed  infant  until,  at  least,  after  the  cutting  of  some  of  its  teeth  ;  and, 
further,  experience  shows  that  the  presence  of  unaltered  starch  in 
the  diet  of  young  infants  is  prone  to  excite  disorders  of  the  stomach 
and  bowels. 

A  consideration  of  these  facts  renders  it  evident  that  foods  belong- 
ing to  this  group  should  be  avoided  altogether  before  the  infant  has 
cut  any  teeth.  Their  addition  to  the  diet  after  that  period  will 
undoubtedly  furnish  the  child  with  an  increased  amount  of  protein 
and  carbohydrate,  but  such  articles  as  rusks,  bread-pap,  oat  flour, 
and  rice^  will  do  so  quite  as  efficiently,  are  as  easy  of  digestion,  and 
have  the  practical  advantage  of  being  very  much  cheaper. 

It  may  be  convenient  to  sum  up  at  this  point  what  we  have  learnt 
as  to  the  practical  rules  for  guidance  in  the  feeding  of  infants. 

1.  Breast  milk  is  always  to  be  preferred  ;  •  humanized  milks,' 
though  right  in  theory,  are  not  found  to  be  perfect  substitutes  in 
practice. 

2.  If  the  child  does  not  gain,  or  loses  weight,  on  the  breast,  try 
mixed  feeding,  using  the  breast  along  with  modified  cow's  milk. 

3.  If  the  breast  is  inadmissible,  a  healthy  infant  may  be  reared  on 
pure  sterilized  cow's  milk ;  a  feeble  infant  will  require  modified  cow's 
milk. 

4.  The  simplest  method  of  modification  is  by  dilution  plus  the 

^  See  Berlin.  Klin.  Woch.,  1895,  xxxii.  201,  and  a  paper  by  Carstens  at  the  67ten 
Versammlung  Naturforscher  und  Arzte  zu  Liibeck,  1895,  Med.  Abth.,  p.  161,  also 
Parker  in  Medical  Society's  Transactions,  1887,  x.  319.  The  whole  subject  has 
been  discussed  more  recently  by  Corlette  ('  A  Review  of  the  Subject  of  Starch 
Digestion  in  Young  Infants,'  Australasian  Medical  Gazette,  1905,  xxiv.  i)  ;  and  by 
Cautley  ('  Starch  Digestion  in  Babies  '),  Lancet,  1909,  ii.  1343. 

•  The  starch  of  oats  and  rice  is  more  easily  digested  by  infants  than  any  other. 


472  FOOD  AND  DIETETICS 

addition  of  cream  and  sugar ;  but  where  expense  is  no  objection, 
one  of  the  humanized  milks  or  *  fettmilch '  may  be  employed. 

5.  If  the  infant  is  unable  to  digest  cow's  casein,  even  when  the 
milk  is  much  diluted,  partial  peptonization  may  be  employed. 

6.  Condensed  milks  should  only  be  used  temporarily — e.g.,  during 
digestive  disturbance  or  where  fresh  milk  is  unobtainable.  The 
addition  of  fat  will  always  be  necessary. 

7.  Few  proprietary  foods  in  the  market  possess  any  real  advantage 
over  the  best  brands  of  condensed  milk,  and  they  should  all  be 
avoided  as  complete  foods  for  infants  if  fresh  milk  is  obtainable. 

If  used  before  the  child  has  cut  its  teeth  as  additions  to  a  diet  of 
milk,  those  only  should  be  employed  in  which  the  starch  is  entirely 
converted  into  soluble  forms.  The  patent  foods  in  which  the  starch 
is  unconverted  possess  no  advantages  as  additions  to  the  diet  of  older 
children  over  such  simple  articles  as  oat-flour,  rusks,  and  rice,  and 
are  considerably  more  expensive. 

In  those  rare  cases  in  which  an  infant  seems  incapable  of  digesting 
the  casein  of  cow's  milk  even  when  peptonized,  it  may  be  necessary 
to  have  recourse  to  various  artificial  mixtures,  such  as  whey  and 
cream,  white  of  egg  and  whey,  bread  jelly,^  or  raw  meat  juice. 

Midelton'  strongly  recommends  the  use  of  eggs  in  such  cases. 
He  advises  the  following  method  of  procedure  for  an  infant  weighing 
6  pounds  or  more  at  birth  : 

During  the  first  two  days  after  birth  beat  up  the  raw  white  of 
a  large  new-laid  hen's  egg,  add  to  this  water  to  make  8  ounces, 
also  40  grains  of  pure  cane-sugar.  Strain  through  butter  muslin. 
Put  I  ounce  of  this  into  the  feeding  bottle,  stand  it  in  hot  water 
at  no"  until  the  food  is  raised  to  g8°  F.     Feed  every  hour  and  a  half. 

On  the  third  or  fourth  day  add  5  minims  of  the  yolk  of  the  egg  and 
5  minims  of  raw  meat  juice  to  each  feed. 

Increase  the  quantities  gradually  as  the  child  grows  older,  and 
also  add  cod-liver  oil  emulsion  to  each  feed,  say  5  minims  of  a 
40  per  cent,  preparation. 

*  Bread  jelly  is  prepared  as  follows :  A  thick  slice  of  bread  (4  ounces)  is 
baked  in  a  basin  of  cold  water  for  six  or  eight  hours  and  then  squeezed  out. 
The  pulp  is  gently  boiled  in  a  pint  of  fresh  water  for  an  hour  and  a  half.  The 
gruel  thus  made  is  strained,  rubbed  through  a  fine  hair  sieve,  and  allowed  to 
cool,  when  it  forms  a  smooth  jelly.  Enough  of  this  is  mixed  with  warm  water  to 
make  a  food  of  the  consistence  of  thin  cream  ;  a  little  white  sugar  may  be  added 
(Cheadle). 

*  Brit.  Med.  Journ.,  1907,  i.  1302, 


DIET  AFTER  WEANING 


473 


The  Feeding  of  Older  Children.* 
After  weaning — which  should  take  place  not  later  than  the  tenth 
month — the  diet  becomes  of  a  more  solid  character.  The  same 
principles  must  be  observed  in  its  composition,  however,  as  in  the 
case  of  infants  ;  that  is  to  say,  the  building  material  and  fat  must  be 
relatively  more  largely  represented  than  in  the  diet  of  adults. 

The  importance  of  a  sufficiency  of  protein  in  the  diet  of  children 
can  hardly  be  exaggerated.  Much  of  the  feebleness,  flabbiness,  and 
pallor  of  the  children  of  the  poorer  classes  in  large  towns  is  no  doubt 
due  to  a  lack  of  it.  There  is  reason  also  to  believe  that  a  similar 
deficiency  may  be  a  cause  of  the  stunted  and  ill-developed  bodies 
which  such  children  often  show.  The  dearness  of  meat  is  largely 
responsible  for  these  conditions  * 

The  following  computations  have  been  made  of  the  amount  of 
each  nutritive  ingredient  reciuired  at  different  ages^  : 


Age. 

Protein. 

Fat. 

Carbohydrate. 

i§  years  . . 

,.     42  5  grammes. 

35  grammes. 

100  grammes 

2          ,,        •• 

..     455 

>• 

36 

no 

3       ..      •• 

..     50 

•1 

38 

120 

4       ..      •• 

..     53 

•• 

4i-f 

•• 

135 

5       ..      •• 

..     56 

43 

145 

8  to  9  years 

..     60 

•• 

44 

150 

12  to  13 

..     72 

•• 

47 

245 

14  to  15     ,, 

..     79 

„ 

48 

270 

Atwater's  calculation  is  as  follows : 

A  child  under  2  years  requires  03  the  food  of  a  man  at  moderate  work. 

A  child  of  3  to  5  years  requires  0-4 

A  child  of  6  to  9  years  requires  0-5 

A  child  of  10  to  13  years  requires  o'6 

A  girl  of  14  to  16  years  requires  0-7 

A  boy  of  14  to  16  years  requires  o-8 

The  ratio  of  building  material  (protein)  to  carbohydrate  and  fat  is 
as  I  :  4-2  -  4-8  in  the  average  child's  diet.  In  that  of  the  adult  at 
moderate  work  it  is  as  i  :  5-3  -  5*5.  It  will  be  noted  also  that  fat  is 
relatively  more  abundant  in  the  diet  of  the  child.  There  is  i  part  of 
fat  to  37  of  carbohydrate  in  the  child's  diet,  while  the  proportion  in 
the  adult  is  i  to  4  (Atwater),  i  to  4*8  (Moleschott),  and  i  to  8*8 
(Voit). 

1  For  a  discussion  of  this  subject  see  Dr,  Joseph  E.  Winter's  '  The  Food 
Factor  as  a  Cause  of  Health  and  Disease  during  Childhood  '  (New  York  :  William 
Wood  and  Co.,  1902). 

2  See  also  Clement  Duke's  '  School  Diet,'  second  edition,  chapter  iii. 

'  Schroder,  '  Ueber  die  Ernahrung  8-15  jahriger  Kinder,'  Archiv.  f.  Hygiene, 
1886,  iv.  39.  See  also  diagram,  p.  47,  and  a  paper  by  Heubner  ('  Eine  Betrach- 
tung  ueber  die  Ernahrung  des  kindes  jenerseits  der  Saugliogsalters, '  in  Jacobi's 
'  Festschrift,'  p.  290), 


474  FOOD  AND  DIETETICS 

Roughly  speaking,  a  child  of  five  requires  half  as  much  fat  and 
building  material  as  a  full-grown  man  doing  a  moderate  amount  of 
work,  but  only  one-third  as  much  carbohydrate ;  while  a  boy  of 
fifteen  will  require  as  much  of  every  ingredient  as  a  full-grown  man 
leading  a  sedentary  life. 

One  must  now  say  a  few  words  as  to  the  sources  from  which  the 
different  ingredients  of  the  diet  should  be  derived. 

Even  for  some  time  after  weaning,  cow's  milk  should  still  be  the 
chief  source  of  protein.  It  may  be  supplemented  at  the  end  of  the 
first  year  by  small  quantities  of  yolk  of  egg,  and  chicken,  fish,  and 
a  little  underdone  meat  may  gradually  be  added.  These  animal 
substances  are  the  best  sources  of  protein,  because  they  contain  it  in 
a  concentrated  and  easily-digested  form.  It  is  possible,  however,  to 
rear  healthy  children  on  a  diet  the  protein  part  of  which  is  almost 
entirely  derived  from  vegetable  sources,^  especially  if  the  child  is  able 
to  lead  an  active  and  out-of-door  life. 

Thus,  a  German  author  has  recorded  the  case  of  an  institution  in 
which  only  one-eighth  of  the  protein  in  the  children's  diet  was 
derived  from  animal  sources,  and  yet  the  inmates  were  all  well 
nourished  and  fully  developed.  He  attributes  this  good  result  to 
the  fact  that  the  children  were  working  out  of  doors  most  of  the  day, 
and  were  accustomed  to  the  diet  from  their  infancy. 

In  most  cases,  however,  it  is  safer  to  supply  at  least  one-third  of 
the  total  protein  required  in  an  animal  form.^ 

The  best  vegetable  protein-yielders  for  children  are  oats  (oat  flour, 
groats,  and  rolled  oats),  wheat  (whole  wheat  flour,  macaroni,  semo- 
lina, or  such  patent  wheat  foods  as  Opmus  and  Florador),  such 
preparations  of  maize  as  hominy  and  cerealine,  and,  amongst  the 
pulses,  lentil  flour. 

Fat  should  be  derived  from  such  sources  as  good  milk,  butter,  the 
yolk  of  egg,  and  bacon.  Difficulty  is  often  found  in  getting  the 
child  to  take  enough  fat,  but  its  importance  in  the  diet  is  such  that 
pains  should  be  taken  to  educate  the  child  in  this  respect.  By 
giving  it  in  a  state  of  fine  division  the  difficulty  may  often  be  over- 

*  See  cases  described  by  Schroder,  loc.  cit.,  p.  453. 

'  '  During  the  period  of  growth,'  says  Clement  Dukes  ('  School  Diet,'  p.  32), 
•  there  should  be  a  tolerably  even  balance  between  the  amounts  of  farinaceous 
and  vegetable  food,  with  a  large  preponderance  of  animal  food,  the  total  supply 
required  being  largely  in  excess  of  that  demanded  by  adults,  in  order  to  supply 
the  material  necessary  for  growth  and  development  as  well  as  wear  and  tear.' 
He  is  assuming,  of  course,  that  regular  daily  exercise  is  enforced.  He  is  of 
opinion  that  growing  boys  should  have  meat  twice  a  day — once  to  make  good 
wear  and  tear,  and  once  to  provide  for  growth.  The  total  daily  allowance  should 
be  9^  ounces  of  cooked  meat. 


DIET  OF  CHILDREN 


475 


come.  Thus,  butter  spread  on  bread  or  mixed  with  mashed  potato 
may  be  taken  when  more  sohd  fat  would  disagree  or  be  refused. 
Suet  pudding  also  contains  fat  in  an  easily-digested  form. 

If  any  carbohydrate  be  added  to  the  diet  at  all  before  the  teeth  are 
cut,  it  should,  as  we  have  seen,  be  in  a  soluble  form.  In  other 
words,  it  should  consist  of  some  form  of  sugar  or  dextrin,  starch 
being  excluded.  Even  up  to  the  end  of  the  first  year  it  is  well  to 
avoid  purely  starchy  foods,  unless  in  very  limited  amount.  It  is  at 
this  period  that  one  of  the  patent  foods,  in  which  the  starch  is 
partially  digested,  may  be  of  service.  After  the  first  year  more 
solid  starchy  food  may  be  given.  Rice,  potato  and  oat  flour  are 
the  most  easily  digested  forms.  Biscuits  or  rusks,  too,  are  more 
easily  digested  than  ordinary  bread,  because  the  high  degree  of  heat 
to  which  they  have  been  exposed  ruptures  many  of  the  starch  grains, 
and  converts  part  at  least  of  their  contents  into  soluble  forms. 

The  following  is  an  analysis  of  two  such  preparations : 

Rusks  (Montgomerie's).  Dorina  Nursery  Biscuits. 

Dr.  Gregory's 
Analysis. 
Water   ..         ,,         ,,        794 
Protein.,         ,,         ,,        9-41 
Starch  ..         .,         ,,      4733 
Maltose  ..         ,.       1662 

Dextrin  ,,         ..       1058 

Fat        988 

Ash        ..         ..         ..         1-24 

Robb's  Nursery  Biscuits  are  also  a  serviceable  preparation  of  a 
similar  sort. 

Bipsine  Rusks  are  made  from  malted  wheat  with  the  addition  of 
casein.  They  contain  15  per  cent,  of  protein,  and  are  said  to  be 
rendered  more  digestible  by  having  been  treated  with  pepsin. 
Nurso  Rusks  ^  are  very  similar.  Both  of  these  are  of  much  higher 
nutritive  value  than  ordinary  rusks. 

Arrowroot,  cornflour,  Oswego,  sago  and  tapioca  are  useful  forms 
of  starch,  which  may  be  given  in  the  form  of  puddings,  but  they 
possess  no  advantage  over  rice,  and  it  must  be  remembered  that 
they  are  practically  devoid  of  protein. 

Sugar  is  one  of  the  most  important  forms  in  which  carbohydrate 
can  be  added  to  the  diet  of  children.  The  great  reduction  in  the 
price  of  sugar  which  has  taken  place  in  recent  years  is  probably  one 
of  the  causes  of  the  improved  physique  of  the  rising  generation. 
The  fear  that  sugar  may  injure  children's  teeth  is  largely  illusory. 

>  Callard  and  Co. 


Dr.  Jago's 

Analysis. 

Water      .. 

« •         • 

69 

Protein    . . 

•  •         • 

"■5 

Starch 

•  •         . 

60-4 

Maltose    . . 

. .         • 

14-2 

Other  soluble  matters  . 

60 

Phosphoric 

acid 

03 

Rest  of  ash 

.. 

04 

476  FOOD  AND  DIETETICS 

The  negroes,  who  live  largely  on  sugar-cane,  have  the  finest  teeth 
the  world  can  show.  If  injudiciously  taken,  sugar  may,  however, 
injure  the  child's  appetite  and  digestion.  The  craving  for  sweets 
which  children  show  is  no  doubt  the  natural  expression  of  a  physio- 
logical need,  but  they  should  be  taken  with,  and  not  between,  meals. 
Chocolate  is  one  of  the  most  wholesome  and  nutritious  forms  of  such 
sweets  (p.  275).  Jam  is  also  an  important  vehicle  for  adding  carbo- 
hydrate to  the  dietary.  The  claims  of  jam  versus  butter  have  already 
been  considered  (p.  136) ;  but  I  would  only  point  out  here  that  so 
great  is  the  importance  of  fat  in  the  diet  of  childhood,  and  so  few  the 
forms  in  which  it  can  be  given  when  compared  with  the  abundant 
choice  of  different  varieties  of  carbohydrate,  that  one  must  on  no 
account  allow  jam  to  replace  butter,  or  even  dripping,  as  the 
habitual  accompaniment  of  the  child's  bread. 

The  mineral  matters,  which  are  so  important  for  building  up  the 
bones,  muscles  and  blood  of  the  growing  child,  should  be  chiefly 
derived,  during  the  first  two  years  at  least,  from  milk.  Abundance 
of  milk  in  the  diet  will  ensure  a  sufficient  supply  of  the  three  most 
important  ingredients — lime,  potash  and  phosphoric  acid.^  Eggs, 
too,  are  rich  in  these  elements,  and  the  yolk  of  egg  especially  shares 
with  milk  the  advantage  of  containing  much  phosphorus  in  an 
organic  form.  Iron  is  contained  in  yolk  of  egg,  the  red  meats,  and 
in  such  vegetable  substances  as  oatmeal. 

The  vegetable  salts  of  potash,  which  occur  so  abundantly  in  fruits 
and  green  vegetables,  are  also  of  importance,  and  such  articles 
should  always  find  a  place  in  the  child's  menu. 

Of  beverages  it  need  merely  be  said  that  water  is  the  only  one  suited 
for  young  children,  but  care  should  be  taken  that  it  is  pure.  Alcohol 
in  all  forms  should  be  avoided  as  being  entirely  unnecessary  for 
healthy  children.  Tea  and  coffee  are  also  harmful  to  the  susceptible 
nervous  system  of  the  child,  but  cocoa,  made  with  plenty  of  milk, 
may  be  allowed,  though  it  should  be  regarded,  like  milk,  as  a  food 
rather  than  a  beverage  properly  so  called. 

Schemes  of  diet  for  children  of  school  age  will  be  found  in  the 
work  of  Dr.  Clement  Dukes  already  referred  to.^ 

The  following  schemes  of  diet  for  young  children  illustrate  the 
practical  application  of  the  above  principles  : 

^Dr.  Ferguson,  the  factory  inspector,  concluded  from  careful  continuous 
measurements  of  factory  children  that  between  thirteen  and  sixteen  years  of  age 
they  grow  nearly  four  times  as  fast  on  milk  for  breakfast  and  supper  as  on  tea 
and  coffee. 

»  '  School  Diet,"  p.  174  et  siq.  (London  :  Rivingtons,  1899). 


DIET  OF  CHILDREN  477 


I.   Diet  from  9  to   12  Months, 

First  Meal,  7.30  a.m. 
Milk  thickened  with  groats,  oat-flour,  Chapman's  Whole  Wheat  Flour, 
Mellin's  Food,  Savory  and  Moore's  Food,  or  Allenbury  No.  3. 
Second  Meal,  10.30  to  11  a.m. 
Warm  milk,  pure  or  diluted  with  one-third  of  lime-water. 

Third  Meal,  1.30  to  2  p.m. 
Warm  milk,  with  the  addition  of  the  yolk  of  a  lightly  boiled  or  raw  egg. 
A  little  veal  broth  or  good  beef-tea  occasionally  as  a  change. 

Fourth  Meal,  5  p.m. 
Same  as  first. 

Fifth  Meal,  9  to  10  p.m. 
Warm  milk. 
During  this  period  the  use  of  a  bottle  should  be  gradually  discontinued,  and 
the  child  fed  with  a  spoon  or  accustomed  to  drink  out  of  a  feeding  cup  or 
ordinary  cup. 

The  amount  of  milk  taken  in  the  course  of  the  day  should  not  exceed  two  pints. 
If  the  child  be  thirsty,  he  may  be  given  a  little  water  between  meals. 

From  about  the  tenth  month  onwards,  somethmg  to  chew  should  be  given 
occasionally,  such  as  a  rusk  or  crust,  or  a  piece  of  sponge  cake  or  stale  bread- 
and-butter. 


II.  Diet  from  12  to  18  Months. 

First  Meal,  7.30  a.m. 
A  breakfast-cupful   of   milk   thickened  with    groats,  fine  oatmeal,  whole 

wheat  flour,  or  hominy. 
Bread  or  rusks  and  milk  as  a  change. 

Second  Meal  about  11  am. 
A  cupful  of  warm  milk,  pure  or  with  the  addition  of  one-third  lime- water. 

Third  Meal,  i  to  1.30  p.m. 
Beef-tea,  mutton  or  chicken  broth,  thickened  with  bread  crumbs  or  sieved 

potato  ;  as  a  change,  the  yolk  of  a  lightly  boiled  egg. 
Some  milky  rice  or  bread  pudding,  with  the  addition  of  some  of  the  pulp 
of  a  roasted  apple  or  the  pulp  of  stewed  prunes. 
Fourth  Meal,  5  p.m. 
Milk  and  bread  and-butter. 

Fijth  Meal,  9  p.m. 
Warm  milk. 


478  FOOD  AND  DIETETICS 


III.  Diet  from  i8  Months  to  3  Years. 

Fust  Meal,  8  a.m. 
Porridge  and  milk,  followed  by  the  yolk  of  a  lightly  boiled  egg  or  bread 

dipped  in  bacon  fat.     Stale  bread,  crisp  toast  or  a  rusk. 
Milk  to  drink. 

Second  Meal,  12.30  to  i  p.m. 

A  little  pounded  or  minced  chicken  or  underdone  meat  or  fish. 
Milk  pudding  and  stewed  fruit. 
Water  to  drink. 

Third  Meal,  4.30  p.m. 
Bread-and-butter  ;  sponge  or  other  plain  cake  occasionally. 
Milk. 

Fourth  Meal,  6.30  p.m. 
Warm  milk  and  a  biscuit. 


L  479  J 


CHAPTER  XXVII 

THE  PRINCIPLES  OF  FEEDING  IN  DISEASE 

In  this  and  the  succeeding  chapter  we  shall  consider  the  use  of 
food  as  a  therapeutic  agent  in  the  treatment  of  the  sick.  In  dealing 
with  this  part  of  the  subject,  it  will  be  well  to  confine  our  attention 
as  far  as  possible  to  the  discussion  of  principles,  and  to  avoid  those 
detailed  instructions  for  the  dietetic  management  of  particular  cases 
which  find  their  appropriate  place  in  text-books  of  therapeutics.  If 
the  general  principles  involved  are  once  fairly  grasped,  the  know- 
ledge we  have  already  acquired  as  to  the  composition  and  uses  of 
different  foods  should  be  sufficient  to  guide  us  in  drawing  up  a 
dietary  suited  to  any  ordinary  case  of  illness.  Nor  can  one  deal  in 
such  a  book  as  this  with  the  methods  of  preparing  food  for  the  sick, 
or  invalid  cookery,  no  matter  how  important  some  acquaintance 
with  that  art  must  always  be  to  the  practical  physician. 

In  deciding  upon  the  dietetic  management  of  any  case  of  disease 
it  is  important  to  bear  in  mind,  what  is  often  forgotten,  that  a  patient 
is  not  a  mere  bundle  of  separate  organs,  but  an  organic  whole,  and 
that  the  diet  must  often  be  directed  to  the  needs  of  the  man  rather 
than  to  those  of  his  malady.  The  evil  results  of  a  forgetfulness  of 
this  fact  are  often  seen.  A  patient's  general  nutrition  may  become 
seriously  impaired,  for  instance,  through  well-intentioned  efforts  to 
lighten  the  labours  of  his  stomach,  or  his  heart  may  become  enfeebled 
in  consequence  of  a  regimen  designed  to  lessen  the  work  of  his 
kidneys.  The  important  factor  of  idiosyncrasy  must  also  be  borne 
in  mind,  and  full  recognition  made  of  the  fact  that  different  individuals 
react  differently  to  the  same  diet  just  as  they  do  to  the  same  drugs. 
Nor  must  it  be  supposed,  as  the  laity  are  apparently  tempted  to  do, 
that  diet  is  a  universal  panacea  which  can  be  counted  upon  to 
prevent  or  to  cure  all  diseases.  On  the  contrary,  it  has,  like  other 
remedial  agents,  only  a  limited  place  in  therapeutics,  and  the  few 
diseases  which  specially  lend  themselves  to  dietetic  treatment  may 


48o  FOOD  AND  DIETETICS 

be  divided  into  the  following  groups:  (i)  Fevers;  (2)  disorders 
of  metabolism,  e.g.,  diabetes,  obesity,  gout;  (3)  affections  of  the 
stomach  and  bowels ;  (4)  disorders  of  the  circulation  and  blood  ; 
(5)  diseases  of  the  organs  of  excretion. 

Before,  however,  one  passes  to  the  separate  consideration  of  these 
groups,  it  is  advisable  to  point  out  a  few  practical  rules  which  should 
always  be  present  to  one's  mind  in  drawing  up  any  scheme  of  diet 
for  a  patient.     They  are  these : 

1.  In  acute  disease  it  is  well  to  recommend  a  special  plan  of  diet; 
in  chronic  cases  it  is  often  more  convenient  simply  to  forbid  those 
articles  which  are  likely  to  prove  harmful. 

The  next  two  rules  are  corollaries  to  the  first. 

2.  Before  recommending  any  article  it  is  well  to  ascertain  whether 
the  patient  likes  it,  and  how  it  agrees  with  him. 

3.  No  article  should  be  forbidden  unless  one  has  good  reason  for 
doing  so. 

4.  Unless  there  is  some  strong  contra-indication,  attention  should 
always  be  paid  to  the  wishes  and  tastes  of  the  patient.  This  rule 
was  first  formulated  by  Hippocrates  in  the  aphorism,  '  Such  food  as 
is  most  grateful,  though  not  so  wholesome,  is  to  be  preferred  to  that 
which  is  better,  but  distasteful  * ;  and  Sydenham  recognised  its  value 
when  he  wrote :  '  More  importance  is  to  be  attached  to  the  desires 
and  feelings  of  the  patient,  provided  they  are  not  excessive  or 
dangerous,  than  to  doubtful  and  fallacious  rules  of  medical  art.' 

5.  If  any  article  of  food  disagrees,  it  is  better  to  reduce  the 
quantity  of  it  taken  than  to  cut  it  out  of  the  dietary  altogether. 

6.  Changes  of  diet  should,  if  possible,  be  made  gradually. 

7.  One  should  never  prescribe  a  diet  for  a  patient  without  having 
first  ascertained  what  his  habits  are  as  regards  work  and  exercise. 

These  rules  require  no  comment. 

1.  Principles  of  Diet  in  Fever. 

There  are  few  departments  of  practical  medicine  in  which  opinion 
has  undergone  a  greater  revolution  than  in  the  question  of  fever 
diet.^  Hippocrates  fed  his  fever  cases  simply  upon  wine  and 
'  ptisan,'  or  thin  barley  gruel,  and  this  lowering  plan,  first  practised 
for  centuries  on  the  sole  weight  of  his  authority,  was  afterwards 
endorsed  by  the  erroneous  pathological  doctrine  first  promulgated 
by  Broussais,  that  fevers  proceeded  from  irritation  of  the  intestinal 

1  For  a  full  account  of  the  history  of  the  subject,  see  J.  Uffelmann,  '  Die  Diat 
in  den  Acut-fieberhaften  Krankheiten,'  1877. 


FOOD  IN  FEVER  481 

mucous  membrane,  and  therefore  demanded  a  starvation  diet.  His 
contemporary,  Brown,  though  perhaps  not  much  nearer  the  truth 
in  his  pathology,  was  better  advised  in  his  practice  when  he  taught 
that  fevers  were  '  asthenic '  diseases,  and  required  to  be  treated  by 
liberal  feeding.  It  was  not  until  about  the  middle  of  the  nineteenth 
century,  however,  that  Graves,  discarding  all  pathological  doctrines, 
and  guided  simply  by  the  results  of  observation,  came  to  the  con- 
clusion that  the  popular  starvation  method  was  wrong,  and  intro- 
duced the  modem  practice,  ever  since  adopted,  of  *  feeding  fevers.' 

The  prevailing  system  at  the  present  time  may  be  fairly  described 
as  that  of  feeding  a  fever  patient  up  to  the  limits  of  his  digestive 
capacity  with  fluid  or  semi-fluid  food,  except,  perhaps,  in  the  case  of 
some  abdominal  fevers.  The  reaction  against  the  starvation  plan 
has,  it  will  be  admitted,  gone,  if  anything,  rather  too  far,  and  the 
danger  now  is  that  too  much  rather  than  too  little  nourishment  may 
be  given. 

Any  lingering  doubts  as  to  the  wisdom  of  the  feeding  plan  tend  to 
be  dispelled  by  the  results  of  recent  research,  which  have  shown 
(i)  that  the  free  administration  of  food  does  not,  as  was  formerly 
supposed,  tend  to  raise  the  temperature  of  feverish  patients  ;^  and 
(2)  that  the  food  is  twt  merely  poured  into  a  digestive  apparatus 
unable  to  deal  with  it,  for  the  absorption  of  light  articles  of  diet,  at 
any  rate,  goes  on  almost  as  perfectly  in  the  febrile  as  in  the  non- 
febrile  state.2 

Granted,  then,  that  the  liberal  administration  of  food  in  fever  is 
justified  on  grounds  alike  of  experience  and  pathology,  we  have  next 
to  inquire.  What  nutritive  constituents  should  the  diet  of  fever 
chiefly  contain  ? 

A  study  of  the  metabolic  changes  in  fever  may  be  expected  to 
afford  us  some  light  here.  Extensive  investigation  into  these 
changes  in  recent  years  has  tended  to  show  that  the  leading  charac- 
teristic of  the  metabolism  of  fever  is  a  great  increase  in  the  destruc- 
tion of  nitrogen-containing  tissues,  while  the  mainly  carbonaceous 
components  of  the  body,  such  as  fat,  are  affected  in  a  much  smaller 
degree. 

The  reason  for  the  increased  destruction  of  nitrogenous  tissues  in 
fever  appears  to  be  twofold :  First,  and  probably  mainly,  it  is  due 
to  simple  inanition,  to  the  fact  that  less  food  is  reaching  the  tissues 

^  Von  Hoesslin,  Virchow's  Archiv.,  1882,  Ixxxix.  95,  303.  He  found  that  in  cases 
of  typhoid  the  temperature  on  days  when  food  was  administered  was  only  from 
oil"  C.  to  o'3*  C,  higher  than  on  starvation  days. 

'  Ibid.     See  also  Leyden's  *  Handbuch  der  Ernahrungstherapie, '  p.  403. 

31 


48a  FOOD  AND  DIETETICS 

than  is  required  to  meet  their  output  of  heat.  In  part,  however,  it 
seems  also  to  be  due  to  the  fact  that  the  '  toxins '  which  produce 
fever  exert  a  specially  destructive  influence  on  the  protein  con- 
stituents of  the  body. 

This  being  so,  it  seems  natural  to  suppose  that  the  chief  dietetic 
indication  in  fever  must  be  to  supply  a  large  proportion  of  protein 
in  the  diet.  Actual  observation,  however,  has  shown  that  it  is  im- 
possible to  bring  about  a  condition  of  nitrogenous  equilibrium  in 
acute  fevers  on  any  feasible  quantity  of  food.  The  reason  for  this 
probably  is,  that  although  one  may  cover  the  waste  which  is  due  to 
simple  inanition,  it  is  impossible  to  prevent  that  which  is  brought 
about  by  the  destructive  action  of  toxins  on  the  cells.  Practically, 
therefore,  the  administration  of  a  large  quantity  of  protein  in  the  diet 
fails  to  achieve  the  desired  result,  no  matter  how  strongly  it  may  be 
indicated  theoretically.  The  consumption  of  much  nitrogenous  food 
has  also  this  disadvantage,  that  it  tends  to  flood  the  circulation  with 
the  products  of  nitrogenous  waste,  already  too  abundantly  present, 
thus  increasing  the  strain  thrown  upon  the  kidneys,  and  at  the  same 
time,  in  all  probability,  tending  to  bring  about  a  condition  of  toxaemia, 
to  which  some  of  the  symptoms  of  fever  are  no  doubt  due. 

We  shall,  therefore,  better  attain  our  object  of  limiting  protein 
destruction  by  seeing  that  the  '  protein-sparers '  are  abundantly 
represented  in  the  diet  rather  than  by  devoting  too  much  attention 
to  the  proteins  themselves. 

Now,  the  protein-sparers,  as  we  have  seen,  are,  in  order  of  their 
importance,  gelatin,  carbohydrates,  and  fats.  The  use  of  the  first 
of  these  is  restricted  by  the  fact  that  the  end-products  of  its  de- 
struction are  so  similar  to  those  of  proteins  that  they  may  be 
expected  to  produce  the  same  results  as  these  in  the  circulation, 
while  the  employment  of  the  last  is  rendered  impracticable  by  the 
insuperable  repugnance  which  feverish  patients  exhibit  to  fatty 
foods.  We  therefore  arrive  at  the  conclusion  that  the  diet  of  fever 
should  contain  a  liheral  supply  of  carbohydrates. 

The  contention  that  mineral  matters  should  also  be  freely  repre- 
sented— a  contention  based  entirely  upon  theoretical  grounds — has 
already  been  dealt  with  (p.  io6). 

These  being  the  dietetic  indications  derived  from  a  study  of  the 
morbid  metabolism  of  fever,  we  may  next  proceed  to  inquire  how 
they  may  best  be  put  into  practice. 

And  first,  by  common  consent,  the  diet  of  fever  is  a  fluid  diet. 
This  is  not  merely  grateful  to  a  thirsty  patient,  but  evades  the 
necessity  of  chewing,  which  the  diminution  of  the  salivary  secretion 


FOOD  IN  FEVER  483 

renders  difficult.  It  has  also  the  advantage  of  supplying  much 
water  to  the  tissues,  of  which  in  fever  they  seem  to  stand  specially 
in  need.  Milk  is  the  simplest,  most  accessible,  and  most  nutritious 
of  fluid  foods,  and  should  always  form  the  basis  of  the  diet.  Four 
pints  of  it  a  day  will  supply  about  1,700  Calories  of  energy  to  the 
body,  and  this,  though  quite  insufficient  for  the  needs  of  health, 
is  usually  enough  to  meet  the  demands  of  a  patient  confined  to  bed, 
especially  in  fevers  of  short  duration,  where  the  body  can  afford  to 
draw  to  some  extent  upon  its  own  resources.  The  milk  may  be 
given  plain  or  diluted  with  some  alkaline  or  effervescing  water 
or  lime-water.  If  the  patient  tires  of  it,  it  may  be  flavoured  with  a 
little  cold  coffee  or  with  caramel  or  malt  extract.  If  it  produces 
vomiting  or  diarrhoea,  it  may  be  necessary  to  give  it  peptonized  or 
to  substitute  koumiss. 

If  less  than  3  pints  of  milk  can  be  got  down  in  the  day,  nutrition 
is  likely  to  become  seriously  impaired,  and  in  that  case  it  may  be 
well  to  '  fortify '  the  milk.  The  amount  of  protein  in  it  may  be 
increased  by  the  addition  of  such  preparations  as  Casumen,  Plasmon, 
or  Somatose,  or  the  proportion  of  fat  may  be  raised  by  the  addition 
of  cream.  For  the  reasons  already  given,  however,  it  is  better  to 
enrich  the  milk  chiefly  by  the  addition  of  some  carbohydrate.  Of 
these  milk-sugar  is  one  of  the  simplest  and  best,  and  is  probably 
not  sufficiently  made  use  of.  One  or  two  teaspoonfuls  dissolved  in 
a  little  hot  water  may  be  added  to  each  tumblerful  of  milk.  The 
value  of  sugar  in  fevers  has  been  specially  insisted  upon  by  Fick  ;i 
and,  of  all  forms  of  it,  milk-sugar,  from  the  comparative  absence  of 
sweetness  which  characterizes  it,  is  probably  best. 

Instead  of  using  sugar,  the  milk  may  be  enriched  by  the  addition 
of  some  cereal  preparation,  such  as  oat-flour,  arrowroot,  or  corn- 
flour, made  in  the  form  of  a  thin  gruel.  Many  of  the  patent  foods, 
such  as  Benger's,  Nestle's,  or  Malted  Milk,  may  here  play  a  useful 
part,  while  some  patients  find  the  addition  of  malt  extract  agreeable  ; 
a  tablespoonful  of  it  may  be  added  to  each  ^  pint  of  warm  milk. 
In  any  case,  it  is  well  to  employ  these  different  devices  in  turn,  for 
patients  quickly  tire  of  any  one  of  them. 

In  addition  to  milk,  soups,  beef-tea,  or  broths  may  be  allowed  in 
the  proportion  of  about  i  pint  a  day,  but  it  should  be  remembered 
that  their  chief  use  is  as  exciters  of  appetite,  and  perhaps  as  slight 
stimulants,  rather  than  as  foods.  They  may  also  be  made  the 
vehicles  for  conveying  carbohydrates  into  the  body  by  thickening 
them  with  baked  flour  or  some  other  simple  farinaceous  prepara- 
l  Zcit.  /.  Klin.  Med.,  1886,  x.  531. 


484  FOOD  AND  DIETETICS 

tion,  or  with  one  or  other  of  the  patent  protein  or  carbohydrate 
foods.  Where  diarrhoea  is  present,  the  use  of  soups,  etc.,  containing 
meat  extractives  is  better  avoided. 

The  consumption  of  beef-juices  in  fever,  though  very  popular, 
is  to  be  deprecated  for  the  reasons  given  in  another  chapter 
(Chapter  VI.);  but  the  egg-white  mixture  already  described  (p.  102) 
may  sometimes  be  a  useful  aid  in  cases  where  very  little  food  can  be 
taken  at  one  time,  and  where  vomiting  is  urgent. 

Jellies  may  also  be  allowed  in  moderation,  those  flavoured  with 
wine  being  perhaps  the  best,  but  it  must  be  recollected  that  their 
nutritive  value  is  but  small. 

As  regards  the  intervals  at  which  food  should  be  given  in  fever, 
one  must  be  guided  chiefly  by  the  digestive  powers  of  the  patient. 
It  is  well  to  begin  with  small  quantities — say  a  wineglassful  of  milk 
— every  hour  or  so,  and  gradually  feel  one's  way  till  a  tumblerful 
can  be  taken  every  two  hours.  Beef-tea  can  be  given  after  every 
two  of  the  milk-feeds,  as  a  change.  As  far  as  possible  the  adminis- 
tration of  food  should  be  confined  to  the  day  hours,  a  little  drink 
only  being  allowed  during  the  night ;  but  if  the  patient  is  much 
exhausted  it  may  be  necessary  to  feed  by  night  also. 

Cold  water  is  the  best  beverage  in  fever,  but  though  the  total 
amount  of  it  need  not  be  restricted,  it  is  well  only  to  allow  a  few 
sips  of  it  at  one  time.  The  excessive  consumption  of  aerated 
beverages  is  to  be  avoided,  as  tending  to  overdistend  the  stomach 
with  gas.  In  addition  to  water,  milk-sugar  lemonade  (a  teaspoonful 
to  the  tumbler,  flavoured  with  a  squeeze  of  lemon-juice),  fruit 
drinks — e.g..,  unfermented  grape-juice  or  raspberry  vinegar  and  water 
— or  Imperial  Drink,  are  all  refreshing,  and  may  be  made  the  means 
of  conveying  some  sugar  into  the  stomach. 

Where  there  is  any  tendency  to  looseness  of  the  bowels,  however, 
it  is  well  to  restrict  the  drink  to  plain  water  or  barley-water.  A  cup 
of  tea  or  coffee  may  also  be  allowed  if  the  patient  desires  it, 
especially  in  the  early  morning,  and  is  probably  too  often  forbidden 
v/ithout  any  sufficient  reason. 

The  use  of  alcohol  in  fevers  is  an  important  matter  which  calls 
for  some  special  discussion.  Hippocrates  recognised  the  value  of 
wine  in  fever,  and  since  his  time  it  has  been  pretty  generally 
employed.  Stokes  of  Dublin  laid  down  certain  imperative  indica- 
tions for  its  use,  and  his  colleague  Graves  devoted  one  of  his  clinical 
lectures  to  a  consideration  of  the  place  which  it  should  take  in  the 
general  treatment  of  fever.     The  advantages  of  stimulants,  however. 


ALCOHOL  IN  FEVERS  485 

were  insisted  upon  more  strongly  by  Todd,^  about  the  middle  of 
the  nineteenth  century,  than  by  any  preceding  English  author,  and 
the  present  general  recognition  of  their  utility  is  no  doubt  largely 
due  to  his  almost  too  strenuous  advocacy.  Indeed,  it  may  be 
questioned  whether  in  this  case  also  the  reaction  in  favour  of  a 
•  stimulating '  treatment  of  fevers  has  not  gone  too  far,  and  the 
administration  of  alcohol  become  too  much  a  matter  of  routine.  In 
a  previous  chapter  we  have  learned  that  alcohol  has  a  stimulating 
influence  upon  the  heart,  that  it  reduces  body  temperature  by  dilating 
the  surface  bloodvessels,  and  that  it  is  in  itself  at  the  same  time 
a  source  of  energy,  and  diminishes  tissue  waste,  especially  the  waste 
of  fat.  All  of  these  properties  mark  alcohol  out  as  an  agent  likely  to 
be  useful  in  the  treatment  of  such  a  condition  as  fever.  It  would  be 
a  mistake,  however,  to  suppose  that  it  requires  to  be  made  use  of  in 
every  case.  Clinical  observation  has  shown  that  it  is  only  impera- 
tively demanded  when  the  following  indications  are  present : 

1.  Failing  circulation,  as  exhibited  (i)in  a  persistently  rapid  pulse 
(120  or  more),  or  if  it  be  weak,  irregular,  unequal,  or  dicrotic ;  (2)  by 
a  faint  or  inaudible  first  sound  of  the  heart.^ 

2.  Nervous  exhaustion,  as  manifested  by  sleeplessness,  low 
delirium,  and  tremors. 

3.  Failure  of  digestive-power,  as  indicated  by  inability  to  take 
food,  diarrhoea,  and  dryness  of  tongue. 

4.  High  temperature,  especially  if  persistent. 

5.  A  bad  general  condition — e.g.,  in  feeble,  exhausted,  elderly,  or 
alcoholic  subjects. 

In  some  special  diseases — i.g.,  malaria,  erysipelas,  and  septic 
poisonings,  alcohol  seems  to  increase  the  resisting-power  of  the 
patient  and  is  almost  always  indicated  on  that  account. 

The  form  in  wMch  alcohol  should  be  given  in  fevers  is  not  a  matter 
of  indifference.  If  one  merely  wishes  to  obtain  its  effects  upon  the 
temperature  and  circulation,  any  pure  form  of  spirit  will  do.  Sound 
malt  whisky  is  as  good  as  any  other.  Where,  however,  there  are 
signs  of  nervous  exhaustion — as,  for  example,  in  the  '  typhoid  state  ' 
— a  preparation  rich  in  volatile  ethers  should  be  selected.  Of  these 
genuine  cognac  is  one  of  the  best,  and  it  is  worth  while  to  pay  a  high 
price  for  it  in  order  to  be  sure  of  having  it  good.  The  ordinary 
so-called  brandy  is  no  better  than  whisky.     Possibly  the  Spanish 

*  •  Clinical  Lectures  on  Certain  Acute  Diseases,'  London,  i860.     Lecture  XIV., 

'  On  the  Therapeutical  Action  of  Alcohol.' 

^  See  Stokes,  Dublin  Med.  Journ.  (ist  series),  1839,  xv.  I. 


486  FOOD  AND  DIETETICS 

brandy  recently  introduced  may  prove  useful,  as  it  is  said  to  be 
rich  in  ethers.  Failing  good  brandy,  one  may  fall  back  on  one  of 
the  stronger  wines,  and  of  these  old  sherry  is  more  highly  ethereal 
than  any  other.*  In  catarrhal  conditions,  and  where  a  tendency  to 
vomiting  is  present,  an  effervescing  wine,  such  as  good,  dry  champagne, 
often  gives  the  best  results.  In  some  forms  of  delirium,  on  the 
other  hand,  such  as  that  due  to  alcoholism,  bottled  stout  seems  to 
exert  a  peculiarly  sedative  influence. 

In  deciding  upon  the  amount  of  alcohol  to  be  given,  and  the 
frequency  of  its  administration,  one  must  be  guided  chiefly  by  the 
urgency  of  the  indications  calling  for  its  use.  Half  an  ounce  of  spirit, 
diluted  with  twice  as  much  water,  or  an  ounce  of  one  of  the  stronger 
wines,  may  be  given  every  four,  three,  or  two  hours,  according  to  the 
effect  produced,  or  even  every  hour  if  occasion  demands  it.  Careful 
observation  of  the  case  will  generally  show  whether  the  right  amount 
b  being  administered.  As  long  as  the  pulse  is  becoming  slower  and 
steadier,  the  skin  and  tongue  more  moist,  the  appetite  better,  and  the 
patient  quieter  and  calmer,  the  alcohol  is  doing  good.  The  results  of 
excessive  dosage  will  usually  first  manifest  themselves  in  the  digestive 
organs  in  the  form  of  flatulence,  eructation,  and  dryness  of  the 
mouth,  with  the  appearance  of  sordes  on  the  lips.  A  tendency  to 
coma,  and  a  persistent  smell  of  alcohol  in  the  breath,  are  also  signs 
that  too  much  is  being  given. 

Diet  in  Special  Fevers. 

The  principles  of  diet  described  in  the  preceding  pages  are 
applicable  to  the  majority  of  cases  of  fever,  but  in  some  one  requires 
to  introduce  liiodifications.  As  has  already  been  mentioned,  the  use 
of  beef-tea  and  all  fluids  containing  the  extractives  of  meat  is  best 
avoided  in  cases  in  which  there  is  diarrhoea.  The  same  holds  good 
for  rheumatic  fever.  In  that  disease  preparations  derived  from  meat 
are  generally  held  to  be  injurious,  and  the  diet  during  the  height  of 
the  attack  should  consist  of  milk  alone  or  diluted  with  some  alkaline 
water.  Alcohol,  also,  is  usually  unnecessary,  and  to  be  avoided  in 
these  cases. 

The  dietetic  treatment  of  typhoid  fever  is  described  in  so  much 
detail  in  all  text-books  of  medicine  that  it  need  not  be  fully  described 
here.  It  is  sufficient  to  point  out  that  the  majority  of  observers  are 
in  favour  of  a  strictly  fluid  diet,  consisting  mainly  of  milk,  in  that 

*  See  Anstie,  '  On  the  Use  of  Wines  ia  Health  and  Disease,"  p.  44  ;  London : 
Macmillan  and  Co.,  1S77. 


DIET  IN  TYPHOID  FEVER  487 

disease,  and  many  recommend  that  even  milk  should  not  be  allowed 
in  large  amount,  but  that  whey  should  be  used  in  its  place. 

If  curds  appear  in  the  stools  the  milk  should  be  peptonizedj  but 
if  the  case  is  running  a  favourable  course  the  nutritive  value  of  the 
diet  may  be  increased  by  the  addition  to  the  milk  of  Plasmcn  or 
Casumen,  Arrowroot,  Maltine,  biscuit  powder,  or  one  of  the  infant 
foods.  Tea  or  coffee  may  be  allowed  in  moderation,  and  the  monotony 
of  the  diet  varied  by  the  addition  of  beef-tea  fortified  by  a  little 
Somatose.  In  prolonged  cases  vegetable  soups  and  fruit  juice 
should  be  allowed,  in  order  to  insure  the  supply  of  a  sufficient 
quantity  of  potash  salts  to  the  blood.  Where  there  is  much  tym- 
panites it  is  well  to  substitute  whey  for  milk. 

It  is  difficult  to  justify  the  conventional  strict  diet  of  enteric  fever 
on  any  grounds  other  than  those  of  experience.  The  widely-spread 
impression  that  solids  are  injurious  on  account  of  the  danger  of  their 
irritating  the  intestinal  ulcers,  and  predisposing  to  haemorrhage  and 
perforation,  can  hardly  be  defended,  for,  as  we  have  already  seen 
(p.  431),  the  intestinal  contents,  by  the  time  the  lower  end  of  the 
ileum  is  reached,  are  always  in  a  fluid  form. 

In  recent  years  a  revolt  against  the  orthodox  practice  has  taken 
place,  and  a  more  abundant  diet  has  been  advocated,  the  extremest 
supporter  of  the  new  view  being  the  Russian  physician  Bushuyez. 
The  diet  which  the  latter  has  adopted  is  certainly  an  extremely 
liberal  one.     The  following  is  the  scheme  of  it : 

7  a.m.  :  Tea  and  a  roll. 

8  a.m.  :  14  oz.  of  gruel  (oatmeal,  barley  or  wheat)  with  butter. 

9  a.m. :  One  or  two  boiled  eggs. 

10  to  II  a.m. :  A  glass  of  milk,  a  roll,  half  a  cutlet,  and  a  bit  of  boiled  meat. 
12  to  12.30  p.m.  :  A  bowl  of  soup  and  a  little  jelly. 

3  p.m. :  Tea  and  a  roll. 

6  p.m. :  A  cup  of  soup,  a  bit  of  chicken,  and  milk  pudding. 

8  p.m.  :  A  roll  and  milk. 

During  the  night  coffee  or  tea,  with  milk,  is  allowed  several  times. 

In  318  cases  in  which  this  diet  was  adopted  the  mortality  was 
only  8*2  per  cent. ;  not  a  single  case  was  lost  from  haemorrhage, 
while  the  general  condition  of  the  patient  was  much  better  than  that 
of  those  fed  on  the  orthodox  lines.  All  the  patients  were  allowed  to 
sit  up  in  bed,  and  many  were  able  to  walk  a  little. 

A  paper  by  Dr.  Morris-Manges' contains  a  full  account  of  the 
results  yielded  by  the  new  diet.  The  writer  himself  used  a  diet 
consisting  of  milk,  soft-boiled  eggs,  custard,  jellies,  chicken,  rice, 
baked  potatoes,  and  strained  cereal  gruels,  in  eight  cases.     He  states 

*  New  York  Medical  Record,  1900,  Ivii.  i. 


488  FOOD  AND  DIETETICS 

that  the  stools  were  always  well  digested,  that  the  diarrhoea  was  not 
increased,  and  that  subsequent  emaciation  and  anaemia  were  very 
slight.  He  had  25  per  cent,  of  relapses,  but  this,  as  he  points  out, 
is  much  higher  than  that  found  by  Bushuyez  and  others  in  a  much 
more  extended  series  of  cases. 

Vaquez^  in  France,  Strouse^  and  Coleman^  in  America,  and,  in 
this  country,  Barrs,*  Marsden,^  and  F.  J.  Smith  ^  also  advocate  the 
more  liberal  diet,  and  report  good  results  from  its  adoption. 

The  present  writer's  own  belief  is  that  here,  as  in  most  forms  of 
illness,  one  must  individualize,  and  that  whereas  in  some  cases  the 
patient  may  be  intolerant  even  of  diluted  milk,  and  must  be  fed 
exclusively  on  whey  and  grape-juice,  yet  there  are  many  cases  in 
which  the  administration  of  semi- solid,  or  even  solid,  food  is  justi- 
fiable at  an  early  stage  of  the  disease.  In  every  case,  of  course, 
insoluble  vegetable  articles,  such  as  the  skins  and  pips  of  fruit, 
currants,  etc.,  should  be  rigidly  withheld,  but  such  things  as  lightly- 
cooked  eggs,  custards,  rusks,  milky  puddings,  bread-sauce,  and  crisp 
toast  are  often  quite  admissible,  and  undoubtedly  help  to  maintain 
strength  and  nutrition,  and  to  shorten  convalescence.  If  a  patient 
expresses  a  wish  for  such  foods  it  is  usually  safe  to  conclude  that 
they  will  not  harm  him.   \ 

Gushing  and  Clarke  "^  recommend  the  administration  of  large 
quantities  of  water  (a  gallon  or  more  in  twenty-four  hours)  in  typhoid 
fever.  This  is  easily  managed  if  given  in  small  quantities  at  frequent 
and  regular  intervals.  They  find  that  patients  are  more  comfortable 
on  this  mode  of  treatment,  and  that  toxic  nervous  symptoms  are 
lessened.     They  regard  it  as  a  valuable  adjunct  to  the  cold  bath. 

2.  Disorders  of  Metabolism. 
Diabetes. 

Whatever  view  one  may  hold  as  to  the  true  pathology  of  diabetes, 
there  is  almost  universal  agreement  as  to  the  value  of  restricting  the 
intake  of  carbohydrates  in  that  disease.  It  may  be  objected  that, 
even  if  one  succeeds  in  doing  this  to  the  point  of  causing  all  sugar  to 
disappear  from  the  urine,  one  has  thereby  only  masked  the  most 
prominent  symptom  of  the  disease,  without  in  any  way  striking  at 
the  root  of  the  complaint.     To  this  it  may  be  replied  : 

I.  That  clinical  experience  has  shown  that  in  many  cases,  by  with- 

*  La  Presse  MM.,  1900,  viii.  73. 

*  Amer.Journ.  0/ Med.  Sctetices,  1909,  cxxxvii.  631.  '  Ibid.,  Jan.,  1912. 

*  Brit.  Med.  Jourti.,  1897,  J-  260.  *  Lancet,  1900,  i.  90. 

*  Brit.  Med.  Journ.,  1906,  ii.  1014. 

'  Amer.  Journ.  of  Med.  Sciences,  1905,  cxxix.  187. 


DIET  IN  DIABETES  489 

drawing  all  carbohydrates  from  the  diet  for  a  time,  one  can  succeed 
in  re-educating  the  tissues  in  their  power  of  dealing  with  sugar,  at 
all  events  to  some  extent,  and  that  a  return  to  an  ordinary  diet  is  then 
no  longer  accompanied  by  a  corresponding  increase  in  sugar  excreted. ^ 

2.  Even  were  it  the  case  that  limitations  of  carbohydrate  ingestion 
had  no  truly  curative  influence,  there  can  be  no  doubt  that  many  of 
the  most  distressing  symptoms  of  which  diabetics  complain,  and 
most  of  the  complications  which  may  cut  short  their  lives,  are  due, 
not  to  the  disease  per  se,  but  to  the  presence  of  an  excess  of  sugar  in 
the  circulating  fluids. 

It  being  granted,  then,  that  limitation  in  the  carbohydrates  in  the 
diet  of  diabetes  is  justified,  one  has  next  to  ask  :  How  are  they  to  be 
replaced  ? 

The  importance  of  this  question  will  be  obvious  when  one  reflects 
that  most  people  are  in  the  habit  of  obtaining  at  least  one-half,  and 
sometimes  even  three-fourths,  of  their  total  daily  supply  of  energy  in 
a  carbohydrate  form.  Obviously,  then,  some  other  source  of  energy 
must  be  found,  unless  one's  patient  is  to  be  starved  to  death,  and 
practically  one  has  to  choose  as  the  substitute  for  carbohydrate 
either  protein  or  fat.  As  to  the  relative  merits  of  these  two  substitutes, 
there  is  not  much  difficulty  in  coming  to  a  decision.  Fat  is  a  com- 
pact source  of  energy,  and  yields,  for  a  given  weight,  two  and  a 
quarter  times  as  many  Calories  as  protein.  In  all  probability,  too, 
it  cannot  act  in  itself  as  a  source  of  sugar.  Protein,  on  the  other 
hand,  is  more  bulky  and  can  certainly  produce  sugar.  In  addition 
to  this  fat  can,  to  a  considerable  extent  at  least,  fulfil  the  protein- 
sparing  function  of  carbohydrates,  and  is  thus  in  every  way  calculated 
to  serve  as  a  substitute  for  these  in  the  food.^  We  conclude,  then, 
that  richness  in  fat  must  be  the  leading  characteristic  of  a  rational 
diabetic  diet. 

The  next  question  which  arises  is  this :  To  what  extent  are  the 
carbohydrates  to  be  restricted  ?  Are  they  to  be  abolished  from  the 
diet  altogether,  or  only  reduced  in  quantity  1  Before  a  reply  to  this 
question  can  be  given,  one  must  ascertain  the  severity  of  the  case 
with  which  he  has  to  deal,  for  in  some  the  tissues  have  lost  their 
power  of  assimilating  carbohydrates  completely,  while  in  others  that 
power  has  only  undergone  impairment. 

^  For  evidence  bearing  upon  this  point,  see  Von  Noorden,  Leyden's  '  Handbuch 
der  Ernahrungstherapie,'  p.  442. 

2  I  am  aware  that  Dunlop  ('Dietetic  Value  of  Fat  in  Diabetes,'  Edin.  Med. 
Journ.,  1896,  xlii.  399)  has  advanced  evidence  in  one  case  to  show  that  fat  does 
not  exert  its  usual  protein-sparing  action  in  diabetes,  but  the  bulk  of  the  clinical 
evidence  available  is  opposed  to  snch  a  conclusion. 


490  FOOD  AND  DIETETICS 

In  order  to  discover  to  which  of  these  classes  the  patient 
belongs,  he  must  be  put  on  a  test  diet  containing  a  known  quantity 
of  carbohydrates.  The  test  diet  should  consist  of  meat  or  fish, 
eggs,  green  vegetables,  and  butter,  with  the  addition  of  4  ounces 
of  bread,^  part  of  which  should  be  eaten  at  each  meal.  If  sugar 
disappears  completely  from  the  urine  on  such  a  diet,  the  case  is 
evidently  a  mild  one ;  if,  on  the  other  hand,  the  urine  only  becomes 
sugar-free  when  the  bread  in  the  diet  is  reduced  in  quantity  or 
altogether  abolished,  the  patient  has  obviously  a  small  degree  of 
tolerance  for  carbohydrates,  and  the  case  is  one  of  medium  severity ; 
whilst  if  sugar  persists  in  the  urine  even  after  all  bread  has  been 
omitted,  and  especially  if  the  aceto-acetic  acid  reaction  is  present,  one 
is  dealing  with  the  severe  type  of  the  disease. 

The  subsequent  regulation  of  the  diet  must  be  determined  by  the 
class  of  case  to  which  the  particular  patient  belongs. 

If  he  can  take  2  ounces  of  bread  without  glycosuria  resulting,  he 
may  be  allowed  i^  ounces  or  its  equivalent  in  some  other  carbo- 
hydrate-containing food.  If  3  ounces  of  bread  are  borne,  allow  only 
2  or  2^  ounces  or  its  equivalent,  and  so  on.  It  is  never  safe  to  feed 
a  patient  up  to  the  limits  of  his  tolerance. 

If,  on  the  other  hand,  sugar  disappears  from  the  urine  on  the 
strict  diet,  but  reappears  whenever  the  smallest  quantity  of  carbo- 
hydrate is  added,  his  diet  must  consist  exclusively  of  protein 
and  fat. 

In  the  third  class  of  case,  that  in  which  sugar  continues  to  be 
excreted  even  on  a  carbohydrate-free  diet^ — and  to  this  class  most  of 
the  diabetics  seen  in  hospital  practice  seem  to  belong — then  a  some- 
what different  method  of  procedure  is  called  for.  It  is  not  wise  to 
restrict  the  carbohydrate  part  of  the  diet  in  such  cases  too  rigidly, 
especially  if  the  aceto-acetic  acid  reaction  be  present  in  the  urine. 
Experience  has  shown  (i)  that  although  in  such  cases  a  restricted 
diet  may  reduce  the  amount  of  sugar  in  the  urine,  yet  the  general 
condition  of  the  patient  suffers,  and  he  is  apt  to  lose  weight ;  (2)  that, 
strange  though  it  may  appear,  a  few  at  least  of  these  cases  actually 
excrete  more  sugar  on  a  diet  rich  in  protein  than  on  one  in  which 
part  of  the  protein  is  replaced  by  carbohydrate.^     In  the  opinion  of 

*  Four  ounces  of  bread  yield  66  grammes  of  sugar. 

•  The  term  '  composite  diabetes  '  was  applied  to  such  cases  by  Dr.  Pavy. 

'  Even  where  everything  is  going  well,  it  is  not  advisable,  when  one  is  dealing 
with  this  type  of  the  disease,  to  give  more  than  500  grammes  (18  ounces)  of 
cooked  meat  a  day,  or  its  equivalent  in  other  forms  of  nitrogenous  food.  The 
author's  own  practice  is  to  give  6  ounces  of  cooked  meat,  2  pints  of  sugar-free 
milk,  3  eggs,  and  4  ounces  of  casoid-meal  bread  daily.  If  the  sugar  excretion 
does  not  fall,  or  if  the  patient  loses  weight,  or  if  coma  threatens,  a  weighed 
quantity  of  ordinary  bread  is  added. 


PROTEIN  AND  FAT  IN  DIABETES  491 

many  good  observers,  too,  such  patients  are  more  apt  to  develop 
diabetic  coma  on  a  very  strict  diet  than  on  one  which  is  more  lax ; 
this,  however,  may  only  be  true  where  the  carbohydrate  is  chiefly 
replaced  by  protein  rather  than,  as  it  should  be,  by  fat. 

There  is  also  the  practical  difficulty  that  in  the  cases  belonging  to 
the  last  group  proteins  must  be  so  much  restricted  that  an  enormous 
consumption  of  fat  is  necessitated  if  nutrition  is  to  be  adequately 
provided  for,  and  it  is  difficult  to  persuade  the  patient  to  take  the 
necessary  quantity  unless  some  carbohydrate  (such  as  bread  or 
potato)  is  allowed  as  a  vehicle  for  carrying  it. 

Summing  up  what  has  been  said  above,  one  may  conclude : 

1.  That  in  mild  cases  of  diabetes  the  diet  should  contain  a  some- 
what greater  amount  of  protein  than  normal,  along  with  a  large 
proportion  of  fat  and  as  much  carbohydrate  as  can  be  tolerated 
without  the  appearance  of  sugar  in  the  urine. 

2.  In  the  more  severe  cases  in  which,  on  a  carbohydrate -free  diet, 
the  sugar  disappears,  but  comes  back  again  whenever  any  starchy 
food  is  taken,  the  diet  should  resemble  the  above,  but  should  contain 
an  extra  quantity  of  fat. 

3.  In  the  severest  cases  of  all,  in  which  sugar  is  excreted  In  the 
urine  even  although  there  be  no  carbohydrate  in  the  food,  the  diet 
should  consist  of  a  somewhat  smaller  proportion  of  protein  than 
normal,  along  with  a  small  amount  of  carbohydrate  and  as  much  fat 
as  the  patient  can  be  induced  to  digest. 

It  will  be  evident  from  these  considerations  that  there  is  no  such 
thing  as  'a  diabetic  diet.'  Every  case  of  the  disease  must  be  treated 
on  its  merits,  and  any  routine  system  of  diet  is  to  be  carefully 
avoided. 

We  may  now  consider  in  greater  detail  what  foods  are  available 
as  sources  of  each  constituent. 

1.  Proteins. — With  regard  to  these  there  is  no  difficulty.  The 
patient  has  the  whole  animal  kingdom  to  choose  from,  though,' in 
cases  where  a  very  strict  diet  is  being  enforced,  it  is  well  to  avoid 
such  articles  as  oysters,  liver  and  sausages,  all  of  which  contain,  or 
may  contain,  some  carbohydrate.  As  a  rule,  the  fatter  meats  and 
fishes  are  to  be  preferred  to  the  leaner.  Of  milk  products,  cheese 
may  be  allowed  in  every  case,  and  Devonshire  cream  may  also  be 
regarded  as  harmless.  The  use  of  milk  itself  will  be  considered 
more  fully  immediately. 

2.  Fat. — The  best  sources  of  fat  are  butter  or  margarine,  bacon, 
the  fatter  meats  (e.g.,  pork),  and  fish  {e.g.,  eel,  mackerel,  and  sardines 
in  oil),  suet,  dripping,  salad  oil,  eggs,  cheese  and  thick  cream.     Of 


492  FOOD  AND  DIETETICS 

these  butter  should  always  be  largely  represented  in  the  diet. 
There  should  be  no  difficulty  in  getting  a  patient  to  eat  J  pound  of 
it  in  the  day,  and  in  some  cases  one  can  get  down  6  ounces,  or  even 
more. 

If  a  small  quantity  of  carbohydrate  is  allowable  in  the  diet,  the 
administration  of  fat  is  much  facilitated,  for  the  carbohydrate- 
containing  food  can  be  made  use  of  as  a  carrier  of  fat.  Thus, 
toasted  bread  may  be  soaked  in  butter  or  bacon-fat,  or  potatoes  may 
be  made  into  a  puree  with  butter  and  cream.  A  given  quantity  of 
mashed  potato,  if  cooked  by  steam,  should  easily  take  up  half  its 
weight  of  butter  and  a  quarter  of  its  weight  of  thick  cream. 

If  carbohydrate  foods  are  rigidly  excluded,  one  has  more  difficulty 
in  persuading  the  patient  to  swallow  an  adequate  quantity  of  fat. 
In  such  a  case  green  vegetables  must  be  our  chief  resource  as  a 
fat-carrier.  Mashed  greens,  from  which  the  water  has  been  removed 
as  far  as  possible  by  squeezing  in  muslin,  should  easily  take  up 
one-third  of  their  weight  of  fat,  and  salads  can  be  covered  with 
about  one-fifth  of  their  weight  of  oil  without  becoming  unduly 
greasy.  Eggs,  too,  can  be  made  rich  in  fat  by  '  scrambling '  them 
with  plenty  of  butter,  and  melted  butter  can  be  used  as  a  sauce  for 
white  fish. 

By  these  devices,  and  by  the  liberal  use  of  fat  bacon,  thick  cream 
and  cheese,  one  can  usually  get  down  a  sufficiency.  It  is  worth 
remembering  that  the  use  of  alcohol  at  meals  greatly  aids  the 
digestion  of  fat,  and  some  writers  recommend  the  administration  of 
chalk  (30  grains  thrice  daily)  with  the  same  object.  I  have  certainly 
seen  cases  where  this  seemed  to  make  the  fat  better  borne,  but  it  is 
apt  to  produce  constipation,  which  of  course  is  a  thing  to  be  carefully 
avoided  in  diabetics. 

In  some  cases  it  may  be  necessary  to  have  recourse  to  the 
administration  of  cod-liver-oil  in  order  to  supplement  the  fat  of  the 
diet,  but  as  far  as  possible  this  should  be  avoided.  Petroleum 
emulsion,  which  is  sometimes  recommended  for  a  similar  purpose, 
is,  as  the  writer  has  shown  elsewhere,  perfectly  useless  as  a 
food. 

3.  Carbohydrates. — The  following  table,  which  shows  (approxi- 
mately) the  percentage  of  carbohydrates  in  some  of  the  commoner 
foods,  may  be  of  help  in  making  a  selection  : 


CARBOHYDRATES  IN  FOODS 


493 


APPROXIMATE  PERCENTAGE  OF  CARBOHYDRATES  IN 
SOME  FOODS. 


Milk  Products 


Cow's  milk  . . 

•     4-5 

Butter-milk 

•     3'3 

Koumiss 

.     1-5 

Cream 

•     3'o 

Devonshire  cream 

•     1-5 

Cereals. 

White  bread 

.  500 

Oatmeal  and  rolle 

d 

oats 

.  65-0 

Rice  . . 

.  76  0 

„     (boiled) 

.  400 

Pulses. 

Green  peas  . . 

.   i6"o 

Dried      ,,     .. 

..  55-0 

French  beans 

..     70 

Revalenta    . . 

.  650 

Soy  beans    . . 

..    28-0 

Peanuts 

.   i7'o 

Roots  and  Tube 

rs. 

Potatoes 

..   200 

Carrots         ..         ..  lo'o 

(cooked)     ..  30 

Turnips        ..          ..  5*0 

,,       (cooked)    ..  o"6 

Radishes  ..  ..  46 
Beetroot      ..         ..no 

,,       (cooked)  ..  28 

Parsnips      ..         ..  14*0 

,,       (cooked)  . .  I '4 

Artichokes  ..          ..  I4'6 

,,          (cooked)  46 

Onions         ..         ..  63 

Vegetables. 

Cabbage  (cooked)  ..  0*4 

Sprouts        ..  ..  34 

Lettuce        ..  ..  2*6 

Spinach  (cooked)  ..  o'8 

Watercress  ..  37 

Cauliflower..  ..  4-7 

Asparagus    ..  ..  2*9 

Cucumber    ..  ..  21 

Rhubarb      ..  ..  2-3 

Celery          ..  ••  3'3 


Leeks  ..         ..  5-8 

Tomatoes     ..         ..  5-0 
Vegetable     marrow 

(cooked)   . .  . .  o'2 

Fruits. 

Apples  and  pears  ..   i2'o 
Stone-fruits  10  to  15 

Gooseberries  (ripe)       90 
,,  (green)     20 

Currants      . .  . .     80 

Strawberries  ..     6'o 

Raspberries  ..     50 

Cranberries  ..     4'o 

Grapes  ..         ..    150 

Melons  ..  ..     7-0 

Bananas       ..  ..   220 

Oranges  (ripe)        ..     89 
(young)    ..     2-0 
Pineapples  . .         . .     95 


Nuts 

Almonds 

Chestnuts 


9  to  12 

..     I0"0 

..   40'o 


Green  vegetables  contain  so  little  carbohydrate  that  they  may  be 
allowed  in  every  case.  Asparagus,  celery,  young  rhubarb,  tomatoes, 
vegetable  marrow,  cucumber  and  mushrooms  may  also  be  regarded 
as  harmless,  but  carrots,  beetroot,  and  parsnips  should  be  avoided. 
Cereals  and  pulses  are,  of  course,  inadmissible,  and  if  the  richer 
carbohydrate  foods  are  allowed  at  all,  bread  and  potatoes  should 
usually  be  selected,  as  the  deprivation  of  these  is  always  keenly  felt 
by  the  patient. 

It  is  important  to  remember  that  potatoes  contain  only  about  one- 
third  as  much  starch  as  bread,  and  so  may  be  given  much  more  freely 
than  the  latter.  If,  for  instance,  a  patient  is  capable  of  taking 
2  ounces  of  bread  daily,  he  may  be  allowed  6  ounces  of  cooked 
potatoes  instead,  if  he  prefers  it.  As  the  fat-carrying  power  of 
potatoes  is  so  great,  such  a  substitution  is  often  an  advantage.  The 
statement  sometimes  made,  however,  that  potatoes  are  harmless  if 
not  actually  advantageous  in  diabetes  ^  is  certainly  erroneous. 

Of  fruits,  green  gooseberries,  early  oranges,  cranberries,  and 
raspberries  are  usually  permissible,  and  are  best  stewed  with 
saccharin  and  eaten  with  thick  cream.  All  sweet  and  dried  fruits 
must  be  avoided. 

1  See  a  paper  by  Sir  James  Sawyer  ('  Improvements  in  Dietetics  of  Diabetes  '), 
Brit.  Med.Journ.,  1904,  i.  537. 


494  FOOD  AND  DIETETICS 

If  one  wishes  to  use  other  carbohydrate  foods  instead  of  bread,  the 
following  equivalents  are  worth  bearing  in  mind  : 

2  oz.  of  bread  contain  as  much  carbohydrate  as  2  oz.  of  pea  or  lentil  flour. 

2  oz.  of  bread  contain  as  much  carbohydrate  as  i  /^  oz.  of  rice. 

2  oz.  of  bread  contain  as  much  carbohydrate  as  i^  oz.  of  oat,  barley,  or 
maize  flour. 

2  oz.  of  bread  contain  as  much  carbohydrate  as  i|  02.  of  cornflour,  arrow- 
root, sago,  tapioca,  or  rice  flour. 

2  oz.  of  bread  contain  as  much  carbohydrate  as  10  to  15  oz.  of  the  sweeter 
fruits. 

2  oz.  of  bread  contain  as  much  carboh3-drate  as  40  oz.  of  apples. 

Iceland  and  Irish  moss,  which  are  often  recommended  for  diabetics, 
are,  as  has  been  shown  elsewhere  (p.  268),  almost  entirely  devoid  of 
nutritive  value. 

The  Cheltine  and  Manhu  Foods  contain  just  as  much  carbo- 
hydrate as  the  corresponding  wheat  products,  and  the  claim  that  the 
starch  in  them  has,  by  a  special  method  of  preparation,  been  rendered 
comparatively  harmless  cannot  be  admitted. 

4.  Albuminoids. — The  use  of  gelatin  is  quite  permissible  in  all  cases 
of  diabetes,  but  the  amount  of  nourishment  which  can  be  obtained  in 
that  form  is  very  small.  Jellies,  of  course,  must  be  made  without 
sugar.  They  can  be  flavoured  with  wine  and  sweetened  with  a  little 
saccharin. 


Some  Special  Articles  of  Food  in  Diabetes. 

I.  Milk. — Opinions  difTer  as  to  the  place  which  milk  should  occupy 
in  the  dietary  of  diabetes.  The  real  question  is  whether  or  not  milk- 
sugar  is  capable  of  assimilation  by  diabetics.  Some  authors  have 
asserted  that  it  is,  and  Donkin*  even  went  so  far  as  to  recommend  a 
purely  skim  milk  diet  in  diabetes,  and  has  recorded  some  apparently 
excellent  results  from  that  plan  of  treatment.  He  states  that  such 
a  regimen  either  greatly  reduces  or  even  altogether  banishes  the 
sugar  in  the  urine.  He  is  careful  to  point  out  that  if  cream 
or  butter  or  any  nitrogenous  food  is  taken  at  the  same  time 
one  does  not  get  these  effects.  The  maximum  quantity  allowed 
was  12  pints  a  day,  and  he  insists  that  the  milk  should  be  fresh, 
not  boiled. 

Whilst  some  of  the  results  recorded  by  Donkin  are  very 
striking,  it  must  be  admitted  that  other  observers  have  failed  to 
confirm  them,  although  Winternitz  and  Strasser  have  reasserted  the 

*  '  On  the  Relation  between  Diabetes  and  Food  ';  London  :  Smith,  Elder  and 
Co.,  1S75. 


MILK  IN  DIABETES  495 

value  of  the  treatment,  even  in  severe  cases.^  On  the  other 
hand,  experiments  made  by  the  subcutaneous  injection  of  sugars 
in  diabetes  have  failed  to  show  that  lactose  is  assimilated  in  that 
disease.^ 

Whatever  the  ultimate  opinion  as  to  the  value  of  an  exclusively 
skim  milk  diet  in  diabetes  may  be,  there  is  pretty  general  agreement 
that  the  addition  of  milk  to  an  ordinary  dietary  in  diabetes  causes  a 
considerable  increase  in  the  amount  of  sugar  excreted.  The 
following  case,  that  of  a  middle-aged  man  with  a  severe  form  of  the 
disease,  may  serve  as  an  illustration  : 

Diet.  Urine.  Sugar. 

Meat  and  fat +  3  oz.  of  bread  ..         ..  1,5000.0.  60  grammes. 

Meat  and  fat +  3  oz.  of  bread  and  3  pints  of 

milk 2,820    „  125        „ 

It  is  true  that,  even  although  the  amount  of  sugar  is  increased,  the 
patient  often  feels  better  and  his  weight  rises  when  milk  is  allowed, 
and  on  that  account  many  observers  advocate  its  presence  in 
the  diet. 

Fortunately,  however,  one  can  easily  obtain  all  the  advantages 
of  milk  without  its  disadvantages  by  getting  rid  of  the  sugar  which 
it  contains,  while  leaving  the  casein  and  fat.  One  then  gets  what 
may,  for  convenience,  be  termed  sugar-free  milk.  Methods  of 
preparing  such  milk  have  been  described  by  Wright'  and  by 
Ringer,*  while  a  very  similar  fluid,  the  chief  ingredients  of  which  are 
cream-fat  and  egg-white,  has  been  elaborated  by  Williamson  ;'  in 
Germany,  also.  Von  Noorden  has  advocated  the  employment  of  a 
similar  artificial  milk.'  With  the  assistance  of  Mr.  Morris,  formerly 
Chief  Dispenser  to  the  London  Hospital,  the  author  has  succeeded 
in  preparing  a  modified  milk  which  contains  merely  a  trace  of  sugar, 
and  which  has  given  excellent  results  in  several  cases.^  The  follow- 
ing are  the  directions  for  making  it : 

1  Centralb.  f.  Inn.  Med.,  1899,  xx.  1137. 

3  Achard  and  Weil,  Arcliiv.  de  Mid.  Ex^er.,  1898   x.  816. 

»  Brit.  Med.  Journ.,  1891,  i.  787. 

*  Ibid.,  1895,  "•  i4>  12  ;  1524. 

^  '  Diabetes  Mellitus,'  p.  334:  Edinburgh  and  London:  Young  J.  Pentland, 
jSgS. 

"  Leyden's  '  Handbuch  der  Ernahrungstherapie,'  p.  475. 

^  Sugar- free  milk  is  now  made  by  Clay,  Paget  and  Co.  according  to  the  above 
formula,  and  can  be  obtained  through  Messrs.  Callard,  Regent  Street,  W.  It 
contains  about  8  per  cent,  of  protein  and  7  per  cent,  of  fat,  and  2  pints  of  it  yield 
1,120  Calories,  or  nearly  ball  the  total  amount  of  energy  required  by  a  patient  at 
rest  in  bed. 


496  FOOD  AND  DIETETICS 

Sugar-free  Milk  for  Diabetic  Feeding. 

Take  i  litre  of  skim  milk,  heat  to  a  temperature  of  38°  C,  and  add  10  c  c.  of 
glacial  acetic  acid,  diluted  with  100  c.c.  of  water.  Mix,  and  allow  the  mixture  to 
stand  for  about  fifteen  minutes.  Collect  the  separated  casein,  and  let  it  drain  on 
very  fine  muslin,  using  no  pressure. 

Remove  the  casein  to  a  mortar,  rub  into  a  smooth  paste,  add  \  litre  of  dis- 
tilled water,  and  strain  as  before.  Repeat  this  washing  of  the  casein  twice. 
Transfer  to  a  mortar,  rub  until  quite  smooth,  and  add  2-5  grammes  of  potassium 
hydrate  dissolved  in  100  c.c.  of  water  (or  as  much  of  the  KHO  as  is  necessary  to 
make  the  product  just  alkaline  to  phenolphthalein). 

Add  100  grammes  of  ordinary  Devonshire  clotted  cream,  5  grammes  of  gelatin 
previously  dissolved,  06  gramme  (i  grain)  of  saccharin,  and  water,  at  about  38°  C, 
up  to  I  litre.     Lastly,  strain  through  fine  m'4slin. 

The  product  tastes  very  much  like  ordinary  cow's  milk,  and  can  be 
taken  either  plain  or  with  some  effervescing  water,  or  it  can  be  added 
to  tea  or  coffee  or  made  into  custards  with  eggs.  In  some  cases  as 
much  as  5  pints  of  it  have  been  taken  in  one  day,  and  it  does  not  seem 
to  have  any  appreciable  effect  in  increasing  the  output  of  sugar.  In 
one  case  a  patient  on  very  strict  diet  excreted  1,000  c.c.  of  urine 
daily  containing  22  grammes  of  sugar.  On  5  pints  of  '  diabetic 
milk  '  and  four  eggs  he  excreted  1,630  c.c.  of  urine  with  28  grammes 
of  sugar.  Another  patient  on  a  fixed  diet  containing  a  known 
quantity  of  carbohydrate  and  i  pint  of  ordinary  milk  excreted 
3,350  c.c.  of  urine  with  180  grammes  of  sugar.  When  the  ordinary 
milk  was  replaced  by  diabetic  milk,  the  quantity  of  urine  fell  to 
2,450  c.c,  and  the  sugar  to  125  grammes. 

The  use  of  such  a  milk  will  be  found  to  be  a  very  great  aid  in 
feeding  diabetics,  especially  when  they  are  unable  to  take  much  meat. 

Of  milk  products,  cream  can  usually  be  allowed  to  diabetics,  and 
the  thicker  it  is  the  better.  Devonshire  cream  is  a  specially  valuable 
form.  Junket,  on  the  other  hand,  contains  a  considerable  quantity 
of  sugar,  and  is  best  avoided.  Koumiss  and  kephir,  though  contain- 
ing considerably  less  sugar  than  ordinary  milk,  are  still  fairly  rich  in 
it,  and  should  be  forbidden  in  any  case  in  which  the  diet  requires  to 
be  at  all  strict. 

2.  Diabetic  Breads. — In  recent  times  a  large  variety  of  breads  have 
been  specially  devised  for  the  use  of  diabetics.  For  the  most  part 
these  are  compounded  of  eggs,  along  with  some  vegetable  substance 
more  or  less  free  from  starch. 

Of  such  substances,  gluten,  the  chief  protein  of  wheat,  was  one  of 
the  first  to  be  employed,^  but  more  recently  the  oily  nuts  (such  as 
the  almond,  cocoa-nut,  and  hazel-nut),  bran,  and  the  soja  bean,  have 
also  been  pressed  into  the  service. 

^  See  Boucbardat,  Cemptes  Rtni.,  1841,  xiii.  942. 


DIABETIC  BREADS  497 

Of  these  products  it  may  be  remarked  that  many  of  them — and 
this  applies  specially  to  the  gluten  breads  {e.g.,  Brusson-Jeune) — are 
by  no  means  free  from  starch  ;*  while  in  the  case  of  others  the  chief 
ingredient  is  cellulose,  which,  of  course,  yields  no  nutriment  to  the 
body.  Indeed,  the  only  really  valuable  substance  which  they  con- 
tain is  fat,  of  which  the  bread  may  be  regarded  as  a  carrier.  This  is 
especially  true  of  the  almond  and  nut  breads.  Bran,  being  incapable 
of  digestion  in  the  human  intestine,  can  serve  no  other  purpose  than 
that  of  adding  to  the  bulk  of  the  diet.  This  fact,  that  the  greater 
part  of  many  diabetic  breads  is  composed  of  wholly  non-nutritive 
matter,  has  not,  I  think,  received  the  attention  which  it  deserves. 

In  addition  to  these  objections,  one  may  say  of  all  '  diabetic  breads ' 
that  they  are  very  expensive,  and  of  most  of  them  that  they  are 
extremely  unpalatable,  and  that  patients  quickly  tire  of  them. 

In  recent  times  casein  has  been  adopted  as  a  basis  for  diabetic 
breads  ;  '  Protene  Diabetic  Bread,' ^  '  Casoid  Bread,' ^  '  Casoid  Meal 
Bread,''  Prolacto  Bread,'  and  Casein  Bread*  are  examples,  and  are 
entirely  free  from  carbohydrates,  besides  being  fairly  palatable. 
Plasmon  Diabetic  Biscuits,  Biogene  Wafers  (Bonthron),  and 
*  Akoll '  Biscuits  (Huntley  and  Palmer)  are  also  starch-free. 

Home-made  diabetic  breads  may  be  prepared  from  such  substances 
as  Roborat  (p.  220),  Aleuronat  (p.  561),  Glidine  (p.  220),  Protene, 
Plasmon,  Biogene,  etc.,  along  with  almond-flour  and  cocoa-nut 
powder.  The  same  ingredients  may  be  used  for  making  puddings 
and  cakes.' 

It  may  be  well  to  point  out  here  that  the  widely-spread  belief  that 
toast  is  less  harmful  to  diabetics  than  bread  is  quite  erroneous. 
Weight  for  weight  toast  contains  more  starch  than  bread,  and  is 
therefore  more  instead  of  less  harmful  than  the  latter. 

3.  Special  Forms  of  Carbohydrate  in  Diabetes.^ — Of  all  forms  of 
carbohydrate,  grape  sugar  is  less  perfectly  assimilated  by  diabetics 
than  any  other.  Next  to  it  come  starch  and  cane-sugar,  the  latter  of 
which  is  always  to  be  avoided.     Inulin  is  said  to  be  well  borne  in 

1  It  is  easy  to  test  any  of  these  breads  by  letting  fall  on  to  the  cut  surface  a 
drop  or  two  of  iodine  solution ;  a  deep  blue-black  coloration  reveals  the  presence 
of  starch.  Each  roll  of  Brusson-Jeune  bread  contains  500  grains  of  starch,  and 
each  '  Energen  '  roll  300  grains. 

-  Protene  Co.,  36,  Welbeck  Street,  W. 

*  Callard  and  Co.,  Regent  Street,  W.         *  Bonthron,  50,  Glasshouse  Street,  W. 

'  Recipes  and  directions  will  be  found  in  such  books  as  W.  H.  and  Mrs.  Poole's 
'Cookery  for  the  Diabetic'  (London,  1903),  Callard's  'Guide  to  Diabetic 
Cookery,"  Senn's  '  Manual  for  Diabetic  Diet  and  Cookery'  (sold  by  Bonthron 
and  Co.),  and  Dr.  R.  T.  Williamson's  '  The  Articles  of  Food  Suitable  for  Diabetic 
Patients  '  (Sherratt  and  Hughes,  1909). 

8  See  Achard  and  "Weil,  Archiv.  de  M4d.  Exper.,  1898,  x.  816,  and  Von  Noorden, 
op.  cit.,ip.  454. 

3a 


498  FOOD  AND  DIETETICS 

mild  cases,  but  is  not  of  much  practical  dietetic  importance.  It  is 
present  in  small  amount  in  the  Jerusalem  artichoke  and  other  Com- 
positae.     The  assimilation  of  lactose  has  already  been  referred  to. 

Much  discussion  has  taken  place  as  to  the  value  of  laevulose  for 
diabetics.^  While  the  earlier  reports  of  its  utility  were  considerably 
exaggerated,  there  is  no  doubt  that  diabetics  utilize  it  better  than 
any  other  form  of  carbohydrate. 

The  chief  importance  of  laevulose  is  as  a  constituent  of  fruits,  in 
which  it  is  sometimes  the  principal  carbohydrate  present.  Early, 
sour  oranges,  for  example,  contain  only  2  to  3  per  cent,  of  carbo- 
hydrate altogether,  of  which  laevulose  is  the  chief;  and  even  sweet 
oranges  have  not  more  than  5  to  7  per  cent.^  For  that  reason  their 
use  may  be  permitted  in  some  cases.  Other  fruits  poor  in  carbo- 
hydrates are  strawberries,  gooseberries,  apricots,  and  melons.  In 
the  form  of  compotes,  sweetened  with  saccharin,  they  may  be  useful 
in  some  cases.  Nuts,  being  practically  devoid  of  carbohydrates 
other  than  cellulose,  while  rich  in  protein  and  fat,  may  be  allowed  in 
almost  every  case. 

Beverages  in  Diabetes. 

The  great  thirst  complained  of  by  most  diabetics  demands  the  free 
use  of  beverages,  and,  fortunately,  there  is  no  reason  to  suppose  that 
these  do  any  harm,  provided  they  be  properly  selected. 

Much  the  same  remarks  apply  here  as  in  the  case  of  fevers. 
Water  is  the  best  beverage,  while  the  aerated  waters  should  be 
indulged  in  more  sparingly.  Citric  acid  lemonade  (10  grains  to  the 
pint,  sweetened  with  ^  ounce  of  glycerine  or  a  little  saccharin)  is  also 
a  pleasant  thirst-quencher. 

Tea  and  coffee  may  be  allowed  freely,  and  may  be  taken  with 
cream  or  sugar-free  milk,  and  sweetened  with  saccharin  if  preferred. 
Cocoa,  though  often  forbidden,  contains  so  little  starch  that  it  is  not 
likely  to  do  harm.  Of  course,  pure  cocoa  should  alone  be  selected. 
It  also  may  be  made  with  sugar-free  milk. 

Alcoholic  beverages  are  extremely  useful,  and  one  can  rarely 
afford  to  dispense  with  them  altogether.  Alcohol  is  not  merely  in 
itself  a  valuable  food  in  diabetes,  acting  both  as  a  source  of  energy 
and  as  a  sparer  of  protein  and  fat,  but  it  has  also  the  further  advan- 
tage of  aiding  greatly  in  the  digestion  of  fat,  of  which,  as  has  been  so 
often  insisted  upon,  every  diabetic  must  freely  partake.     Under  its 

1  See  Hale  White  and  Grube,  Zeit.  f.  Klin.  Med.,  1894,  xxvi.  332. 
«  Kraus,  Zeit.  /.  Dial,  und  Pliysik.  Tlierapie,  1898,  p.  69. 


ARRANGEMENT  OF  MEALS  IN  DIABETES        499 

use  the  output  of  sugar  and  nitrogen  is  lessened,  whilst  the  pro- 
duction of  acetone  is  also  decreased.^  With  the  exception  of  malt 
liquors,  liqueurs,  and  sweet  wines,  almost  any  form  of  alcoholic 
drink  may  be  allowed.  In  cases  where  a  very  stringent  diet  is  being 
enforced,  recourse  may  be  had  to  one  or  other  of  the  sugar-free 
alcoholic  drinks,  a  list  of  which  has  been  given  elsewhere  (see  foot- 
note, p.  394).  If  the  patient  is  gouty  as  well  as  diabetic,  alcohol  is 
better  avoided. 

Arrangement  of  Meals  in  Diabetes. 

As  diabetics  usually  suffer  considerably  from  hunger,  it  is  well  to 
make  the  meals  rather  frequent. 

Where  a  limited  quantity  of  carbohydrate  is  allowed,  it  will  be 
found  convenient  to  adopt  the  suggestion  put  forward  by  Von 
Noorden,  and  arrange  that  each  meal  shall  consist  of  one  principal 
dish  and  an  '  extra '  in  which  the  allowance  of  carbohydrate  is  con- 
tained. For  example,  in  a  severe  case  in  which  2  ounces  of  bread 
and  2  ounces  of  potato  are  being  allowed,  the  diet  may  be  made  up 
of  the  following  constituents : 

Meat        4  oz. 

Bacon       ..         ..         ..  2   ,, 

Fish         2   „ 

Butter 6  ,, 

Green  vegetables  ..  2   ,, 

Divided  into  meals,  this  would  work  out  as  follows: 

Breakfast.— Chiet  dish  :  Bacon  and  a  scrambled  egg.  Extra:  I  oz.  of  bread, 
toaisted,  with  plenty  of  butter.  Tea  with  diabetic  milk  and  saccharin,  il  a.m. : 
J  pint  of  diabetic  milk. 

Df««<rr.— Chief  dishes:  Meat  (4  oz.),  green  vegetables  and  butter.  Custard 
pudding,  made  of  diabetic  milk  and  2  eggs.  Extra:  Potatoes  (2  oz.)  and 
plenty  of  butter      Water,  spirit  and  water,  or  some  dry  wine. 

Tea. — An  egg:  bread  (i  oz.),  plenty  of  butter.  Tea  or  coffee  with  diabetic 
milk  and  saccharin. 

5M//>i?n— Fish  (2  oz.)  with  butter  sauce,     i  pint  of  diabetic  milk. 

This  diet  contains  about  85  grammes  of  protein  and  225  grammes 
of  fat,  not  reckoning  the  carbohydrate,  and  has  an  energy-value  of 
about  2,500  Calories. 

By  the  use  of  some  alcoholic  drink  at  dinner  and  supper  the  value 
of  the  diet  could  easily  be  raised  to  3,000  Calories,  and  upon  this 
most  patients  will  be  found  to  gain  weight. 

In  milder  cases,  in  which  more  protein  is  advisable,  one  can 
easily  double  the  quantity  of  meat  or  fish,  and  the  proportion  of  fat 

1  See  Benedict  and  Torok  {Zeit.f.  Klin.  Med.,  1906,  Ix.  329). 


Eggs         4 

Diabetic  milk     ..         ..  2  pints. 

Bread 2  oz. 

Potatoes  ..         ..         ..  2   ,, 


500  FOOD  AND  DIETETICS 

can  be  raised  by  the  use  of  thick  cream  in  tea,  and  its  addition  to 
mashed  potatoes. 

In  cases  in  which  a  strict  diet  is  being  enforced,  one  can  replace 
the  bread  and  potatoes  by  an  extra  allowance  of  milk  and  eggs  and 
a  more  liberal  use  of  alcohol. 

In  mild  cases  in  which  there  is  a  considerable  tolerance  for  carbo- 
hydrates, the  quantity  of  fat  in  the  diet  can  be  considerably  reduced. 

It  need  hardly  be  said  that  the  above  diet  is  merely  given  as  a 
sample  ;  its  protein  and  fat-containing  ingredients  may  be  varied  very 
greatly  according  to  the  taste  of  the  patient.  It  will  be  found, 
however,  I  think,  to  be  well  suited  for  routine  hospital  use. 

Even  in  mild  cases  with  a  considerable  tolerance  for  carbohydrates, 
Von  Noorden  recommends  that  the  patient  should  be  subjected  at 
intervals  of  a  year  or  so  to  a  short  course  of  very  strict  diet.  He 
believes  that  in  this  way  the  power  of  the  cells  to  assimilate  carbo- 
hydrate may  be  conserved. 

In  cases  in  which  there  is  marked  acetonuria,  the  so-called 
'  oatmeal  cure '  is  sometimes  useful.  It  is  in  no  sense  a  cure  for 
diabetes,  and  is  only  to  be  used  in  cases  in  which  the  glycosuria  has 
first  been  reduced  to  as  low  a  level  as  possible  by  the  ordinary  rules 
of  diet.  It  is  not  suitable  for  very  severe  cases,  and  should  not  be 
repeated  oftener  than  once  every  three  weeks.  The  '  cure  *  should 
be  preceded  by  three  days  of  a  diet  consisting  only  of  green  vege- 
tables, fat  bacon,  butter,  and  about  five  eggs,  along  with  tea,  coffee, 
and  alcohol ;  then  for  three  days  8  ounces  of  oatmeal  in  the  form 
of  porridge  or  oatcake  are  given,  along  with  4  ounces  of  butter  and 
five  eggs,  with  tea,  coffee,  and  alcohol.  This  must  be  followed  by 
another  day  of  the  '  vegetable  '  diet  before  the  patient  returns  to  his 
ordinary  '  strict  *  diet. 

The  oatmeal  diet  may  be  combined  with  the  vegetable  diet,  the 
essential  feature  being  to  allow  no  other  form  of  carbohydrate  on 
the  oatmeal  days.  It  is  scarcely  possible  to  carry  out  the  oatmeal 
cure  satisfactorily  unless  the  patient  is  under  treatment  in  a  home 
or  sanatorium  ;  and  many  English  patients,  at  all  events,  are  inclined 
to  regard  such  a  '  cure '  as  being  on  the  whole  worse  than  the 
disease. 

In  the  worst  cases  of  acetonuria  of  all,  in  which  any  attempt  to 
restrict  the  intake  of  carbohydrates  brings  on  threatenings  of  coma, 
there  is  nothing  to  be  done  but  to  allow  carbohydrates  freely.  In 
such  cases,  however,  a  day's  starvation  about  once  a  week,  on  which 
day  the  patient  is  kept  in  bed  on  a  diet  of  tea,  broth,  and  alcohol, 
is  often  helpful  in  delaying  the  onward  progress  of  the  disease. 


DIABETIC  COMA  501 

If  coma  threatens  or  has  set  in,  it  is  best  to  abandon  the  strict  diet, 
and  to  feed  the  patient  mainly  on  skim  milk^  and  Vichy  water,  with 
a  liberal  use  of  alcohol  in  a  dilute  form. 

The  dietetic  treatment  of  the  so-called  gouty  glycosuria  met  with 
in  elderly  people  is  essentially  the  same  as  that  of  true  diabetes.  It 
is  impossible,  indeed,  to  draw  any  sharp  line  of  distinction  between  the 
two  conditions  except,  that  whereas  the  glycosuria  of  young  subjects 
is  not  only  persistent  but  progressive,  that  of  older  people,  though 
it  may  persist,  often  does  not  tend  to  increase — i.e.,  there  is  no  pro- 
gressive failure  of  assimilation  going  on  as  there  is  in  true  diabetics. 
Most  of  these  cases  will  be  found  to  have  a  considerable  tolerance 
for  carbohydrates,  and  all  that  is  necessary  is  to  keep  the  supply 
below  that  limit.  Should  the  tolerance  be  nil,  the  case  must  be 
managed  on  the  same  lines  as  one  of  true  diabetes.  Alcohol,  it 
should  be  remembered,  is  often  injurious  in  the  glycosuria  of  elderly 
persons,  particularly  when  there  is  coexisting  obesity  or  renal 
disease. 

It  will  be  found  a  great  advantage  to  begin  the  treatment  of  all 
cases  of  diabetes  either  in  hospital  or  in  a  Nursing  Home.  The 
patient  is  then  under  strict  supervision,  and  it  is  much  easier  to 
determine  the  exact  nature  of  the  case  with  which  one  has  to  deal, 
and  the  way  in  which  the  patient  reacts  to  modification  of  diet  and 
to  different  forms  of  starch.  In  addition  to  this,  the  discipline  to 
which  the  patient  is  subjected  has  a  wholesome  influence  upon  him, 
and  serves  to  educate  him  in  methods  of  dieting  himself  when  he 
returns  to  his  ordinary  life. 

It  only  remains  to  point  out  that  a  dietary  suitable  for  diabetics  is 
necessarily  an  expensive  one,  from  the  fact  of  its  consisting  mainly 
of  animal  food  and  fat,  and  this  will  be  found  to  be  a  great  obstacle 
to  the  proper  treatment  of  diabetes  amongst  the  poor.  In  many 
cases  there  is  room  here  for  charitable  aid  in  enabling  the  patient  to 
get  abundance  of  such  articles  as  butter,  cream,  and  meat,  without 
which  proper  treatment  of  the  case  is  impossible. 

^  Skim  milk  is  preferable  to  ordinary  milk,  for  there  is  some  reason  to  suppose 
that  the  presence  of  fat  in  the  diet  favours  the  production  of  acetone  (see  a  paper 
by  Dr.  F.  Schuman-Leclercq  in  the  Dublin  Journal  of  Medical  Science,  igoi.cxii.  i6i, 
entitled  'The  Influence  of  Food  on  the  Excretion  of  Acetone').  A  case  of 
acetonuria  in  which  acetone  disappeared  when  the  amount  of  fat  in  the  diet  was 
reduced  has  also  been  recorded  by  Pollatschek  {Zeit.  /.  Didt.  und  Physik.  Therapie, 
1904,  viii.  163-165).  Lenne,  however  {ibid.,  1904,  viii.  253),  brings  forward 
evidence  opposed  to  the  view  that  the  amount  of  fat  in  the  diet  has  any  influence 
in  the  production  of  acetonaemia.  The  whole  subject  is  discussed  in  detail  by 
Bosanquet,  Goulstonian  Lectures,  1905  (Lect.  III.,  Lancet,  1905,  i.  1053). 


C  502 1 


CHAPTER  XXVIII 
THE  PRINCIPLES  OF  FEEDING  IN  DISEASE  (continued) 

The  Dietetic  Treatment  of  Obesity. 

The  occurrence  of  obesity  is  almost  invariably  an  indication  of  a 
disproportion  between  the  intake  of  potential  energy  in  the  form  of 
food  and  the  output  of  actual  energy  in  the  form  of  work.  Some- 
times the  fault  lies  in  an  unduly  large  income,  sometimes  in  too 
small  an  expenditure ;  not  unfrequently  both  factors  co-operate. 
There  would  seem,  however,  to  be  another,  but  very  limited,  group 
of  cases,  in  which,  owing  to  some  inherent  lack  of  vital  power  in  the 
cells  of  the  body,  fat  is  able  to  accumulate  even  in  the  absence  of 
any  excessive  intake  of  food.  This  may  explain  some  of  the  cases 
in  which  patients  become  fat  even  although  they  are  very  moderate 
eaters.  There  is  reason  to  believe,  however,  that  this  is  a  very  rare 
event,  and  that  in  the  majority  of  cases  in  which  it  is  alleged  to 
occur,  the  patient  is  really  the  victim  of  self-deception.* 

It  is  obvious  from  these  considerations  that  the  proper  treatment 
of  obesity  must  consist  either  in  a  reduction  in  the  total  number  of 
Calories  of  energy  supplied  in  the  food,  or  in  an  increase  in  the 
output  of  energy  in  the  form  of  work,  or  in  a  combination  of  these 
methods. 

An  increased  expenditure  can  be  achieved  by  the  use  of  suitable 
muscular  exercises,  but  that  method  of  treatment  does  not  concern 
us  here,  and  we  may  now  direct  our  attention  to  the  best  means  of 
diminishing  the  intake  of  energy  in  the  form  of  food.  And  first  one 
may  ask,  Which  chemical  ingredient  of  the  food  is  it  most  important 

1  See  Hirschfeld,  » Ueber  den  Nahrungsbedarf  der  Fettleibigen,'  Berliner 
Klimk,  April,  1899,  Hft.  130,  1-22  ;  also  Hoffmann,  Leyden's  '  Handbuch  der 
Ernahrungstherapie,'  p.  540;  Von  Noorden,  'Die  Fettsucht,"  p.  24,  Vienna, 
1900;  and  Rubner,  '  Beitrage  zur  Ernahrung  im  Knabenalter,'  Berlin,  1902. 
The  obesity  of  young  subjects,  however,  seems  sometimes  to  be  due  to  a  con- 
genital peculiarity  of  metabolism,  and  not  to  any  excessive  consumption  of  food. 
Such  cases  do  not  lend  themselves  to  dietetic  treatment. 


DIET  IN  OBESITY  503 

to  reduce — the  proteins,  carbohydrates,  or  fats?  Physiological  in- 
vestigation has  shown  that  all  of  these  ingredients  may  serve  as 
sources  of  fat  in  the  body  if  consumed  in  excess,  but  the  risk  of 
proteins  being  converted  into  fat  seems  to  be  very  small.  As  regards 
the  relative  dangers  of  an  excess  of  carbohydrates  or  fats  in  the  food, 
classical  authorities  on  the  subject  are  not  altogether  agreed,  and,  as 
we  shall  see  immediately,  schemes  of  diet  for  the  obese  have  been 
drawn  up,  in  some  of  which  the  carbohydrates  have  been  specially 
restricted,  while  others  are  characterized  by  a  limitation  of  fats. 

The  progress  of  research  into  metabolism  in  obesity,  however,  has 
shown  that  the  question  is,  after  all,  and  as  far  as  the  mere  storage 
of  fat  is  concerned,  one  of  indifference.  The  only  essential  point  is 
to  reduce  the  total  number  of  Calories  supplied  in  the  form  of  food, 
and  whether  this  should  be  accomplished  by  limiting  the  carbo- 
hydrates or  the  fats,  or  both,  is  purely  a  matter  of  convenience,  and 
one  which  must  be  decided  chiefly  by  the  tastes  and  habits  of  each 
individual  patient.^ 

The  next  problem  which  presents  itself,  then,  is,  To  what  extent 
should  the  total  number  of  Calories  in  the  diet  be  reduced  ?  Here, 
again,  no  hard-and-fast  rule  can  be  laid  down.  In  some  cases,  such 
as  in  the  very  young,  in  whom  probably  a  marked  congenital 
tendency  to  the  disease  exists,  it  is  difficult  to  keep  the  undue  forma- 
tion of  fat  in  check  at  all.  In  others,  such  as  the  very  old,  it  is 
probably  unwise  even  to  make  the  attempt,  while  in  particular 
instances — for  example,  those  in  which  the  chief  deposit  of  fat  is  in 
the  abdomen — treatment  is  always  peculiarly  difficult.  In  an  average 
case,  however,  such  as  is  most  commonly  met  with  in  the  later 
periods  of  middle  life,  one  must  be  guided  mainly  by  the  degree  to 
which  the  obesity  has  developed,  and  in  judging  of  this  it  is  always 
better  to  go  by  the  general  appearance  of  the  patient  rather  than  by 
tables  of  height  and  weight. 

Following  the  teaching  of  Von  Noorden,  and  assuming  that  an 
average  man  of  this  age  requires  to  be  supplied  with  from  2,500  to 
3,000  Calories  of  energy  daily  to  meet  his  current  expenditure  in 
heat  and  work,  one  may  divide  cases  into  three  groups : 

I.  Those  in  which  it  is  merely  necessary  to  reduce  the  diet  by 
one-fifth,  which  means  the  supply  of  2,000  Calories.  This  can  best 
be  done  by  cutting  out  sugar  by  reducing  the  supply  of  fat  and 
carbohydrates,  and  by  restricting  the  consumption  of  alcohol. 

This  plan  is  only  likely  to  be  successful  if  it  can  be  combined  with 

'  See  Von  Noorden,  op.  cit. 


504  FOOD  AND  DIETETICS 

a  free  use  of  muscular  exercise,  and  in  any  case  the  loss  of  weight 
under  it  can  only  be  very  slow. 

2.  In  severer  cases  the  diet  may  be  reduced  two-fifths,  which  means 
supplying  only  1,500  Calories.  Here  it  will  be  necessary  still 
further  to  reduce  the  amount  of  fat  in  the  diet,  and  to  limit  the  con- 
sumption of  bread ;  and  in  this  case  also  the  loss  of  weight  is  apt  to 
be  slow,  unless  the  patient  can  at  the  same  time  take  at  least  a 
moderate  amount  of  active  exercise.  Von  Noorden  states  that  he 
prefers  this  scheme  to  any  other,  because,  while  it  usually  gives  good 
results,  it  is  never  attended  by  any  disagreeable  consequences. 
He  specially  recommends  it — 

(a)  In  patients  who  are  being  treated  at  home,  and  are  continuing 
to  follow  their  usual  occupation. 

(b)  In  patients  who  can  go  into  the  country,  and  take  a  moderate 
amount  of  exercise  without  requiring  medical  supervision. 

(c)  In  those  for  whom,  owing  to  the  presence  of  visceral  com- 
plications, a  rapid  '  cure '  might  be  dangerous. 

{d)  As  the  habitual  diet  in  advanced  cases  in  which  periods  of 
greater  restriction  are  being  observed. 

3.  The  third  degree  of  diet  is  that  in  which  the  total  Calories 
supplied  are  reduced  three-fifths — i.e.,  to  about  1,000  to  1,500 
per  day. 

This  group  includes  all  the  classical  'systems'  of  diet  for  obesity, 
as  is  shown  by  the  following  table : 


System. 

Protein. 

Carbohydrate. 

Fat. 

Clnlnvitt 

Grammes. 

Grammes. 

Grammet. 

\^Ul-Uf  *t* 

Banting   . . 

..     172 

81 

8 

1,100 

Oertel  (maximum) 

..     170 

120 

45 

1,600 

(minimum) 

..     156 

75 

25 

1,180 

Ebstein    . . 

..     102 

47 

85 

1.300 

Hirschfeld  (maximum] 

1        139 

67 

65 

1,400 

,,          (minimum) 

100 

50 

41 

1,000 

Von  Noorden     , . 

••     155 

112 

28 

1,366 

Some  of  these  demand  a  word  of  description. 

Banting  System. — This  scheme  of  diet  was  first  popularized  by  the 
writer  whose  name  it  bears,^  although  it  had  previously  been  recom- 
mended in  France  by  Leon. 

Banting  suffered  from  an  extreme  degree  of  obesity,  so  great,  he 

tells  us,  as  to  render  him  unable  to  tie  his  own  shoe,  and  to  compel 

him    to    go    downstairs    backwards.      Having    consulted    various 

physicians  without  success,  and  having  tried  the  effects  of  violent 

1  See  '  A  Letter  on  Corpulence  addressed  to  the  Public,'  by  William  Banting; 
London,  1863. 


DIET  IN  OBESITY  505 

rowing  exercise  and  a  course  of  Turkish  baths,  he  was  finally 
advised  by  an  aural  surgeon,  Dr.  Harvey,  to  abstain  from  bread 
milk,  butter,  sugar,  and  potatoes,  •  which  had  hitherto  been  the  main 
and,  as  he  thought,  innocent  elements  of  his  existence,'  and  to  adopt 
instead  the  following  diet : 

Breakfast. 

4  to  5  ounces  of  beef,  mutton,  kidneys,  broiled  fish,  bacon,  or  any  cold  meat 

except  pork ;  a  large  cup  of  plain  tea,  and  a  little  biscuit  or  i  ounce  of 
toast. 

Dinner. 

5  to  6  ounces   of  any  lean  meat   or   fish,  any   vegetable  except   potatoes, 

I  ounce  of  dry  toast,  some  fruit  out  of  a  pudding,  any  kind  of  poultry  or 
game,  and  2  to  3  glasses  of  good  claret,  sherry  or  madeira. 

Tea. 

2  to  3  ounces  of  fruit,  a  rusk  or  two,  and  a  cup  of  plain  tea. 

Supper. 

3  to  4  ounces  of  meat  or  fish  as  at  dinner,  and  a  glass  or  two  of  claret. 

For  a  '  night-cap '  he  was  allowed  a  tumbler  of  *  grog '  without 
sugar,  or  a  glass  or  two  of  claret  or  sherry. 

On  this  regimen  Banting  lost  35  pounds  of  weight  in  thirty-eight 
weeks,  which  is  not  surprising,  considering  that  his  diet  hitherto  had 
consisted  of  bread-and-milk  for  breakfast,  or  a  cup  of  tea  with 
plenty  of  sugar  and  milk,  and  buttered  toast ;  meat,  beer,  much 
bread  (of  which  he  was  always  very  fond),  and  pastry,  for  dinner ; 
a  tea  of  the  same  composition  as  breakfast,  and  a  fruit  tart  or  bread- 
and-milk  for  supper.  He  found  sugar  the  most  fattening  of  all 
foods,  5  ounces  of  it  in  a  week  causing  his  weight  to  rise  i  pound  ; 
and  he  calls  milk,  sugar,  beer,  and  butter  *  human  beans,*  because 
they  have  the  same  effect  in  the  human  subject  that  beans  have  in 
the  case  of  the  horse,  and  he  regards  these  articles  as  'the  most 
insidious  enemy  an  elderly  man  with  a  tendency  to  corpulency  can 
possess,  though  eminently  friendly  to  youth.'  He  adds  :  '  I  can  con- 
scientiously assert  that  I  never  lived  so  well  as  under  the  new  plan 
of  dietary.' 

It  will  be  observed  that  the  chief  chemical  characteristic  of  the 
Banting  system  is  the  great  predominance  of  proteins  in  the  diet, 
and  it  has  been  asserted,  though  with  only  a  limited  degree  of  truth, 
that  owing  to  this  fact  one  is  more  likely  to  insure  a  loss  of  body  fat 
alone  on  it,  and  to  prevent  any  inroads  into  the  muscular  tissues, 
than  by  any  other  plan.^ 

^  For  a  discussion  of  this  subject  see  Dapper,  Zeit.  /.  Klin.  Med.,  1893,  xxiii. 
113,  and  Von  Noorden,  0/.  eit. 


5o6  FOOD  AND  DIETETICS 

Be  this  as  it  may,  the  system  has  certainly  the  advantage  of 
simplicity  and  of  being  easily  regulated,  and  on  this  account  it  is 
likely  to  retain  its  popularity.  It  should  be  pointed  out,  however, 
that  the  large  excretion  of  nitrogen  which  such  a  diet  entails  is  apt 
to  throw  a  severe  strain  upon  the  kidneys,  and  for  that  reason  it  is 
well  always  to  investigate  the  state  of  these  organs  before  embarking 
upon  the  treatment. 

The  chief  characteristic  of  Oertel's  system,^  which  has  been  largely 

popularized  in  Germany,  though  with  some  slight  modification,  by 

Schweninger,  is  that  he  restricts  the  consumption  of  fat  more  than 

that  of  carbohydrates,  and  at  the  same  time  lays  great  stress  on 

limiting  the  amount  of  fluid  in  the  diet.     To  the  discussion  of  the 

latter  point  we  shall  return  later,  but  at  present  the  following  may  be 

taken  as  a  type  of  his  system.     It  is  adapted,  of  course,  to  German 

habits : 

First  Breakfast. 

ij  ounces  of  white  bread,  2  eggs,  a  large  teacupful  of  coffee  with  i  ounce 
of  milk  and  i  lump  of  sugar,  and  (in  some  cases)  J  ounce  butter. 

Second  Breakfast. 

2  ounces  of  lean  meat,  f  ounce  of  coarse  bread,  3J  ounces  of  light  wine  or 
clear  soup. 

Dinner. 

5J  ounces  of  roast  beef  with  salad  or  green  vegetables,  3J  ounces  of  pudding 
and  fruit,  a  tumblerful  of  light  wine,  and  (in  some  cases)  i  ounce  of 
bread. 

Afternooti. 

A  small  cup  of  coffee  as  at  breakfast. 

Supper. 

^  ounce  of  caviare,  5^  ounces  of  chicken  or  game,  J  ounce  of  cheese,  f  ounce 
of  coarse  bread,  a  tumblerful  of  water  or  light  wine. 

Ebstein-  modified  Banting's  diet  by  increasing  the  proportion  of 
fat  and  giving  less  protein,  as  follows  : 

Breakfast. 

A  large  cup  of  tea  without  milk  or  sugar,  2  ounces  of  bread  with  plenty  of 
butter. 

Dinner. 

Soup,  4^  to  5^  ounces  of  meat  with  fat  sauce,  green  vegetables,  fresh  fruit, 
2  to  3  glasses  of  light  wine. 

Afternoon. 
Tea  as  at  breakfast. 

Supper. 

Tea,  one  egg,  fat  roast  meat  or  ham,  smoked  fish,  about  i  ounce  of  bread 
with  plenty  of  butter,  a  little  cheese,  and  fresh  fruit. 

1  Oertel,  '  Twentieth  Century  Practice,'  ii.  625. 

*  '  Corpulence,  and  its  Treatment  on  Physiological  Principles  '  (translated  from 
sixth  German  edition) ;  Wiesbaden  and  London,  1884. 


DIET  IN  OBESITY  507 

Ebstein  gives  the  following  summary  of  his  plan :  '  The  permission 
to  enjoy  certain  succulent  things,  always,  of  course,  in  moderation, 
as,  for  instance,  salmon,  pMe-de-foie-gras,  and  such-like  delicacies, 
reconciles  the  corpulent  gourmet  to  his  other  sacrifices.  These 
consist  in  the  exclusion  of  the  carbohydrates.  Sugars,  sweets  of 
all  kinds,  potatoes  in  every  form,  I  unconditionally  forbid.  The 
quantity  of  bread  is  limited  at  most  to  3  or  3I  ounces  a  day,  and  of 
vegetables  I  allow  asparagus,  spinach,  the  various  kinds  of  cabbage, 
and  the  legumes.  Of  meats  I  exclude  none,  and  the  fat  in  the  flesh 
I  do  not  wish  to  be  avoided,  but  rather  sought  after.  I  permit 
bacon-fat,  roast  pork  and  mutton,  and  kidney-fat,  and  when  no 
other  fat  is  at  hand  I  recommend  marrow  to  be  added  to  the  soups. 
I  allow  the  sauces  as  well  as  the  vegetables  to  be  made  juicy,  as  did 
Hippocrates,  only  for  his  sesam-oil  I  substitute  butter.' 

Hirschfeld's  diet^  resembles  that  of  Ebstein  very  closely : 

Breakfast. 
2  ounces  of  bread,  and  coflfee  without  sugar  or  milk. 

Forenoon, 
2  eggs. 

Dinner. 

Soup  with  2  ounces  of  rice  (weighed  uncooked),  8  ounces  of  lean  meat  boiled 
or  roasted  with  a  little  fat. 

Afternoon. 
Black  coflfee. 

Supper. 

2  ounces  of  cream  cheese,  4  ounces  of  bread,  J  ounce  of  butter. 

Von  Noorden^  gives  a  large  number  of  small  meals,  and  restricts 
fats  more  than  carbohydrates : 

8  a.m. :  3  ounces  of  cold  lean  meat,  i  ounce  of  bread,  a  cup  of  tea  or  coflfee 

with  a  spoonful  of  milk,  but  no  sugar. 
10  a.m. :  i  egg. 

Noon  :  A  cup  of  strong  soup  without  fat. 
I  p.m.  :  A  small   plate  of  clear  soup   {k  la  Julienne   or  k  la  jardiniere), 

5  ounces  of  lean  meat  or  fish,  3^  ounces  of  potatoes,  green  vegetables, 

3^  ounces  of  fresh  fruit. 

3  p.m. :  A  cup  of  black  coffee. 

4  p.m. :  7  ounces  of  fresh  fruit. 

6  p.m. :  A  glass  of  skimmed  milk. 

8  p.m. :  4^  ounces  of  cold  lean  meat  with  pickles,  i  ounce  of  Graham  bread, 
2  to  3  spoonfuls  of  fruit  cooked  without  sugar. 

He  also  allows  two  glasses  of  wine  a  day. 

It  will  be  observed  that  all  of  these  systems,  seeing  that  they  fall 

^  '  Beitrage  zur  Ernahrungslehre  des  Menschen,'  Virchow's  Archiv.,  1888,  cxiv. 
301  ;  and  '  Ueber  den  Nahrungsbedarf  der  Fettleibi^en,'  Berliner  Klinih,  Hit.  130, 
1899. 

2  op.  cit.,  p.  12a. 


5o8  FOOD  AND  DIETETICS 

short  by  at  least  i,ooo  Calories  of  the  number  requisite  to  meet  the 
outgoings  of  the  body,  must  be  regarded  as  starvation  methods  of 
treatment.^  For  this  reason  it  is  never  safe  to  carry  them  on  for 
more  than  a  few  weeks  at  a  time,  during  which  the  patient  must  be 
under  strict  supervision,  and  any  symptoms  of  weakness  or  heart 
failure  carefully  watched  for. 

As  regards  the  relative  advantages  of  the  different  methods,  a  good 
deal  of  diflference  of  opinion  exists,  and  some  patients  will  be  found 
to  prefer  one  plan,  some  another. 

Ebstein  specially  recommended  the  inclusion  of  a  considerable 
amount  of  fat  in  the  diet,  on  the  ground  that,  while  it  does  not  tend  to 
the  production  of  fat  more  than  its  equivalent  of  carb(jhydrate,  it  has 
a  greater  *  satisfying  '  power,  and  tends  to  allay  feelings  of  hunger. 
It  may  be  doubted,  however,  as  Von  Noorden  has  pointed  out, 
whether  this  is  really  true  of  such  quantities  of  fat  as  it  is  safe  to 
allow,  while,  on  the  other  hand,  the  greater  bulk  of  carbohydrate  food 
certainly  tends  to  produce  a  feeling  of  satisfaction. 

The  point,  however,  is  really  one  of  indifference.  Some  patients 
stand  a  limitation  of  fat  better  than  that  of  carbohydrates,  whereas 
in  the  case  of  others  the  reverse  holds  good,  but  as  long  as  the  total 
number  of  Calories  in  the  diet  is  kept  low  fat  must  inevitably 
continue  to  be  lost  from  the  body. 

Whether  or  not  it  is  advisable  to  restrict  the  amount  of  fluids  in 
the  diet,  and  if  so  to  what  extent,  we  shall  proceed  to  discuss 
immediately. 


On  the  Use  of  Particular  Articles  of  Food  in  Obesity. 

In  drawing  up  a  scheme  of  diet  for  the  obese,  it  is  well  to  avoid 
too  great  variety,  for  that  always  tends  to  increase  appetite.  For 
the  same  reason,  all  spices,  condiments,  and  other  articles  that 
increase  the  desire  for  food,  must  be  used  very  sparingly. 

The  following  list  of  the  Calorie  value  of  some  of  the  commoner 
articles  of  food  may  be  of  assistance  in  enabling  one  to  arrive  at 
some  idea  of  their  relative  suitabiUty  as  articles  of  diet  for  the 
corpulent.     (See  also  the  tables  on  pp.  7,  426.) 

*  This  statement  is  hardly  true  for  all  individuals.  The  writer,  for  instance, 
has  recently  had  a  patient — a  lady  of  12  stones— who  lost  no  weight  on  Ebstein's 
diet  for  five  weeks,  although  the  amount  of  energy  yielded  by  her  daily  supply  of 
food  was  less  than  1,200  Calories.  Later  on  she  began  to  lose  weight  at  the  rate 
of  a  pound  a  week. 


DIET  IN  OBESITY  5^9 

Article.  Cahries. 

2  ounces  of  cheese..          224 

1  ounce  of  butter  (enough  to  cover  three  or  four  slices  of  bread)  . .  208 

A  helping  of  cooked  lean  meat  (4  ounces)        196 

A  tumblerful  of  milk         . .         . .         . .         . .         •  •         •  •         •  •  14° 

A  moderately  thick  slice  of  bread  (2  ounces) 138 

,,                 ,,                 ,,            and  butter..          ..         ..          ..  208 

A  heaped  dessert-spoonful  of  milk  pudding     ..  ..  ..         ..no 

One  egg        7° 

One  medium-sized  potato  (2  ounces)     . .          . .          . .          . .         . .  45 

An  ordinary  lump  of  sugar          16 

The  use  of  sugar  should  be  avoided  altogether,  and  saccharin 
employed  as  a  sweetener  instead.  Visible  fat  should  be  removed 
from  meat,  and  the  richer  meats,  such  as  pork,  goose,  etc.,  and  the 
fatter  fishes,  such  as  mackerel,  eel  and  salmon,  interdicted.  Milk 
and  its  products  should  only  be  used  in  moderation,  and  puddings 
must  be  unconditionally  forbidden.  Bread,  also,  is  a  very  dangerous 
food,  but  as  it  can  hardly  be  dispensed  with  altogether,  it  should  only 
be  allowed  in  weighed  quantities.  ^  It  is  well,  too,  to  select  the 
coarsest  sorts  of  bread,  which  contain  much  indigestible  bran,  such 
as  Graham  bread  ;  for  a  given  bulk  of  these  yields  much  less  nutri- 
ment to  the  body  than  an  equal  weight  of  fine  bread.  Potatoes,  as 
the  table  shows,  are  not  nearly  so  dangerous  as  bread,  and  may  often 
be  allowed  in  moderation.  It  is  better  to  avoid  the  other  roots  and 
tubers,  but  green  vegetables  and  mushrooms  may  be  freely  permitted, 
and  their  great  bulk  has  the  advantage  of  producing  a  feeling  of 
satisfaction.  Dried  fruits  as  containing  much  sugar  must  be  strictly 
forbidden,  but  fresh  fruit  may  be  allowed  in  moderation,  and,  if 
stewed,  should  be  sweetened  with  saccharin.  All  made  dishes,  thick 
soups,  sauces  and  pastry  must  be  cut  out  of  the  menu,  as  they  are 
subtle  vehicles  for  the  conveyance  of  much  fat  and  starch  into  the 
body. 

The  arrangement  of  the  meals  must  be  regulated  to  a  large  extent 
by  the  habits  of  the  patient.  Where  it  is  feasible,  most  authorities 
seem  to  prefer  that  they  should  be  small  and  frequent,  as  the  total 
amount  of  food  consumed  is  thus  more  easily  kept  under  control. 

Beverages  in  Obesity. 

The  first  question  to  be  settled  regarding  the  use  of  beverages  in 
obesity  is  whether  or  not  it  is  important  to  diminish  the  total  amount 
of  fluid  in  the  diet  in  that  disease.  The  restriction  of  fluids  was 
first  advocated  by  a  French  military  surgeon — Dancel — in  a  book 

1  Some  of  the  partially  or  entirely  starch-free  breads  and  biscuits  sold  by  the 
makers  of  diabetic  foods  may  be  used  instead  of  ordinary  bread. 


5IO  FOOD  AND  DIETETICS 

published  in  1863.^  He  had  observed  the  Influence  of  water  and 
watery  fluids  in  producing  abdominal  development  in  the  horse,  and 
he  made  reduction  of  fluids  one  of  the  main  principles  in  the  regimen 
which  he  drew  up  for  corpulency.  The  principle  was  subsequently 
adopted  by  Oertel  and  Von  Schweninger,  and  attained  through  their 
advocacy  a  very  considerable  degree  of  popularity. 

Exact  observation,^  however,  has  now  shown  that  the  influence 
which  the  amount  of  water  in  the  diet  exerts  upon  the  production  or 
loss  of  fat  in  the  body  is  very  small  in  amount  and  uncertain  in 
degree,  and  that,  as  a  matter  of  fact,  fat  people  are  less  affected  by  a 
restriction  of  fluids  than  are  lean. 

Dancel  restricted  the  intake  of  fluids  to  7  to  14  ounces  per  day. 
Oertel  allowed  a  daily  maximum  of  2^  pints,  and  Von  Schweninger 
of  about  3  pints,  but  the  latter  made  a  strong  point  of  fluids  not 
being  taken  along  with  solids,  but  rather  between  meals. 

The  opinion  of  most  authorities  at  the  present  time^  seems  to  be 
that  the  restriction  of  fluids  has,  at  best,  only  an  indirect  influence. 
In  the  case  of  some  patients  the  interdiction  of  fluids  at  meals  inter- 
feres with  appetite,  and  so  results  in  less  solid  food  being  consumed. 
In  such  cases  the  method  may  be  of  value,  but  where  no  such  result 
ensues,  the  loss  of  weight  which  results  is  only  temporary,  and  due  to 
a  diminution  of  the  body  fluids.  It  is  probable,  too,  as  Yorke  Davies 
has  pointed  out,*  that  one  reason  why  restriction  of  fluids  has  given 
better  results  on  the  Continent  than  one  sees  in  this  country  is,  that 
in  Germany,  at  least,  restriction  of  fluids  is  very  often  synonymous 
with  restriction  of  beer. 

The  whole  question,  indeed,  is  to  be  regarded  as  one  aflfecting  the 
technique  of  feeding  rather  than  the  physiological  principles  upon 
which  the  dietetic  treatment  of  obesity  is  founded.*  Von  Noorden 
concludes  that  restriction  of  fluids  should  only  be  insisted  upon  when 
the  following  indications  are  present : 

1.  Weakness  of  circulation.  A  dry  diet  is  advisable  here  for  the 
sake  of  the  heart,  apart  altogether  from  the  obesity. 

2.  At  the  commencement  of  many  'cures.*  Here  the  initial  loss  of 
weight  which  the  restriction  of  fluids  brings  about  is  calculated  to 
make  a  great  mental  impression  on  the  patient. 

5.  In  cases  where  the  restriction  results  in  a  diminished  appetite  for  fat- 
forming  foods. 

*  See  also  Bull,  ie  Therap.,  1864,  Ixvii.  44. 

*  Dennig,  Zeit.  f.  Didt.  nnd  Physik.  Therap.,  1809,  ii.  292. 

'  See  a  discussion  on  obesity  reported  in  the  Verhandl.  d.  ^ien  Cong.  f.  Inn. 
Med.,  1885. 

*  '  Foods  for  the  Fat,'  p.  26.  •  See  Von  Noorden,  op.  cit.,  p.  124  et  seq. 


FATTENING  DIET  5i» 

4.  Where  sweat  excretion  is  excessive.  He  considers  that  the  total 
amount  of  fluid  allowed  should  not  be  reduced  below  2^  pints  per 
day. 

Where  a  Banting  or  any  other  very  nitrogenous  diet  is  being 
adopted,  the  restriction  of  fluids  is  to  be  avoided,  as  being  opposed 
to  the  free  elimination  of  the  products  of  nitrogenous  waste. 

Of  the  different  sorts  of  beverages  in  common  use,  water  and  the 
saline  mineral  and  table  waters  may  be  regarded  as  harmless ;  but 
the  sweetened  effervescing  waters,  such  as  lemonade,  should  be 
avoided.  Tea  and  coffee  may  be  freely  permitted,  if  taken  with  little 
milk  and  no  sugar.  Cocoa  is  often  forbidden,  but  the  amount  of 
nutriment  which  an  ordinary  cupful  of  it  contains  is  so  small  as  to 
be  hardly  appreciable.  In  many  people,  also,  it  has  the  advantage 
of  lessening  the  appetite  for  solid  food. 

Alcoholic  beverages  should  be  avoided  as  far  as  possible,  for 
alcohol  is,  as  we  have  seen,  a  direct  sparer  of  fat.  If  a  small  allow- 
ance is  indicated  on  other  grounds — e.g.,  feebleness  of  heart — a  dry 
natural  wine  should  be  selected,  or  its  alcoholic  equivalent  of  well- 
matured  spirit  freely  diluted  with  water.  All  strong  and  sweet  wines, 
liqueurs  and  malt  liquors  should  be  interdicted. 

Fattening  Diet. 

In  the  previous  section  we  have  dealt  with  the  dietetic  methods  of 
reducing  fat.  We  have  now  got  to  consider  the  means  at  our 
disposal  for  increasing  it. 

Generally  speaking,  any  excess  of  food  which  is  supplied  to  the 
body  beyond  the  amount  required  to  meet  the  current  outgoings  of 
energy  in  the  form  of  heat  and  work  will  be  stored  up  in  the  form  of 
fat.  One  does,  however,  meet  with  cases  in  which,  owing  probably 
to  some  failure  of  assimilative  power,  it  is  found  to  be  very  difficult 
to  achieve  the  laying  on  of  fat,  even  although  a  considerable  surplus 
of  food  is  supplied,  but  as  a  rule  one  may  say  that  in  order  to  fatten 
the  body  one  has  merely  to  insure  the  supply  of  an  excess  of  food. 

It  will  be  obvious  that  one  important  means  of  bringing  about 
such  a  surplus  of  income  over  expenditure  is  to  diminish  the  out- 
goings of  energy  from  the  body.  For  this  reason,  rest,  more  or  less 
complete,  is  always  an  important  aid  in  cases  in  which  one  wishes 
to  fatten. 

As  regards  the  constituents  of  the  food  which  are  most  important 
in  respect  of  fattening  properties,  it  may  be  said  that  fat  itself,  owing 
to  the  ease  with  which  it  can  be  stored,  takes  the  first  place.     It  has 


512  FOOD  AND  DIETETICS 

been  calculated  by  Rubner  that  loo  parts  of  fat,  248  of  carbohydrate, 
and  313  of  protein,  are  equivalent  in  fat-forming  power.  Whether 
all  forms  of  fat  are  equally  valuable  in  this  respect  must  be  left 
undecided,  but  it  is  probable  that  some  fats  produce  a  more  stable 
kind  of  adipose  tissue  than  others.^ 

When  one  comes  to  the  actual  construction  of  a  fattening  dietary, 
however,  due  attention  must  be  paid  to  the  powers  of  the  digestive 
organs,  and  for  that  reason  it  is  better  to  see  that  carbohydrates 
and  fats  are  both  abundantly  represented,  rather  than  to  trust  to  one 
or  other  of  them  alone.  Munk  is  of  opinion  that,  in  order  to  insure 
the  laying-on  of  fat,  one  should  supply  90  to  100  grammes  of  fat, 
100  to  no  of  protein,  and  about  500  of  carbohydrate,  daily. 

The  permanent  enrichment  of  the  body  in  protein  (practically  in 
muscular  tissue  and  blood)  is  very  much  more  difficult  of  accomplish- 
ment than  the  mere  deposition  of  a  certain  amount  of  fat.  So  great 
is  the  tendency  for  nitrogenous  equilibrium  to  assert  itself  that  it  is 
almost  impossible  to  bring  about  a  storage  of  protein  in  the  body 
unless  (i)  a  considerable  amount  of  muscvilar  exercise  is  taken  at  the 
same  time,  or  unless  (2)  there  has  been  a  previous  wasting  of  the 
muscles,  such  as  occurs  during  acute  disease. 

In  the  former  case  the  bulk  of  the  muscles  exercised  can,  up  to  a 
certain  limit,  be  increased ;  in  the  latter  the  normal  muscular  develop- 
ment can  be  again  attained.  The  one  process  occurs  during  train- 
ing, the  other  during  convalescence.     In  both  protein  is  stored  up. 

In  practice  the  storage  of  protein  can  be  accomplished,  granted  the 
presence  of  one  or  other  of  the  above  conditions,  either  by  increasing 
the  actual  amount  of  protein  in  the  diet  or  by  raising  the  proportion 
of  protein-sparers.  Weight  for  weight  carbohydrate  is,  it  will  be 
remembered,  a  more  powerful  protein-sparer  than  fat;  but  here, 
again,  in  actually  constructing  the  dietary  it  is  better  to  avail  one's 
self  of  both  ingredients.' 

Practically,  then,  it  comes  to  this,  that  where  one  wishes  to  lay  on 
fat  only,  one  should  increase  the  proportion  of  fat  and  carbohydrate 

1  See  Weir  Mitchell,  '  Fat  and  Blood,'  p.  25. 

"  For  a  discussion  of  this  subject  see  Rosenfeld,  '  Die  Bedingungen  der 
Fleischmast,'  Berliner  Klinik,  1899,  Hft.  127,  1-28.  In  a  more  recent  paper  by 
Kauffmann  ('  Der  Gegenwartige  Stand  der  Lehre  von  der  Eiweissmast,'  Zeit  /. 
Bidt.  und  Physik.  Therapie,  1903,  vii.  355),  the  whole  question  is  carefully  reviewed, 
and  the  conclusion  arrived  at  that  some  protein  probably  can  be  laid  up  in  the 
body,  and  that  this  may  be  accomplished  either  by  an  increase  of  the  protein  in 
the  food  or  by  supplying  a  larger  amount  of  protein-sparers.  The  former  method 
is  preferable,  if  one  does  not  wish  to  increase  the  fat  in  the  body  at  the  same 
time. 

2  See  Wicke  and  Weiske,  Zdt.  /.  Ph^siolog,  Chem.,  1895,  ^'  42i  and  1896, 
xxii.  137. 


DIET  IN  CONVALESCENCE  513 

in  the  food,  laying,  perhaps,  greater  stress  on  the  former ;  but  where 
one  wishes  to  lay  on  protein,  the  proportion  of  that  ingredient  in  the 
food  should  be  increased  as  well,  and  prominence  given  to  the 
increase  of  carbohydrate  rather  than  to  that  of  fat. 

A  fattening  diet  is  wanted  in  three  chief  sets  of  conditions :  (i)  In 
convalescence  from  acute  illness  ;  (2)  in  wasting  diseases,  such  as 
tuberculosis  ;  (3)  in  some  nervous  disorders,  of  which  neurasthenia 
may  be  regarded  as  the  type. 

In  convalescence  the  waste  of  protein  and  fat  which  the  preceding 
illness  has  entailed  must  be  made  good.  Out  of  respect,  however, 
to  the  debilitated  digestive  powers  of  such  a  patient,  one  must 
proceed  with  caution.  There  is  reason  also  to  believe  that  the 
metabolic  conditions  of  fever  continue  for  a  day  or  two  after 
the  temperature  has  fallen,  and  on  that  account  some  observers 
advocate  the  continuance  of  the  fever  diet  for  three  days  after  the 
pyrexia  has  ceased.  One  can  then  begin  to  thicken  the  patient's 
beef-tea,  soups,  and  milk  with  cereal  flours,  and  to  add  other 
farinaceous  foods  to  the  diet.  Many  of  the  patent  malted  foods 
may  be  usefully  employed  here.  The  increase  of  protein  may  be 
accomplished  by  the  addition  of  pounded  meat  to  soups  in  the  form 
of  purees,  and  one  may  gradually  pass  on  to  the  administration  of 
the  more  easily  digested  forms  of  animal  food,  such  as  chicken,  fish, 
and  eggs.  Jellies  are  also  agreeable  to  the  convalescent,  and,  along 
with  custard  or  light  milk  puddings,  are  pleasant  forms  of  protein - 
sparing  food.  The  enrichment  of  the  diet  in  fat  may  be  conveniently 
deferred  till  later,  and  should  be  accomplished  by  the  free  use  of 
cream,  butter,  bacon  and  suet,  or,  if  these  cannot  be  compassed  in 
sufificient  quantity,  one  may  have  recourse  to  cod-liver-oil  (see  also 
p.  568). 

One  of  the  simplest  methods  of  enriching  the  diet  in  wasting 
diseases  is  by  adding  to  it  a  certain  quantity  of  milk.  There  is 
frequent  opportunity  in  cases  of  phthisis  of  observing  the  good  effects 
of  adding  2  or  3  pints  of  milk  to  the  ordinary  diet,  3  pints  represent- 
ing an  addition  of  about  1,000  Calories  to  the  value  of  the  diet.  It 
can  be  taken  both  as  a  beverage  with  the  usual  food  and  also 
between  meals. 

Fat  seems  to  be  of  special  value  in  the  diet  of  tuberculosis,  and 
by  the  use  of  the  more  easily  digested  forms  of  it,  such  as  butter, 
bacon,  pork,  salad-oil  and  cream,  one  has  usually  not  much  difficulty 
in  persuading  patients  to  take  enough  of  it,  even  when,  as  is  not 
unfrequently  the  case  in  phthisis,  a  considerable  natural  repugnance 

33 


514  FOOD  AND  DIETETICS 

to  fat  exists.     Smith  ^  recommended  that  phthisical  patients  shi^uld 
take  the  following  amount  of  fat  daily  : 

As  milk     ..  ..  ..         ..         ..  2;^  ounces. 

,,  butter  ..  ..  ..         ..         ..2        ,, 

,,  bacon  ..  ..  ..         ..  ..  2-4      ,, 

In  meat    ..  ..  ..         ..         ..  i^      ,, 

As  salad-oil  i  ounce. 

,,  suet  in  puddings ^     ,, 

Cream  ad  lib. 

Recently,  however,  there  has  been  manifest  a  reaction  amongst 
those  best  qualified  to  judge  against  the  indiscriminate  stuffing  of 
tuberculous  patients  with  fatty  and  carbohydrate  foods,  and  a 
recognition  of  the  value  and  importance  of  an  increased  supply  of 
protein,  or,  in  practice,  of  a  diet  containing  plenty  of  meat.^  Such  a 
diet  seems  to  increase  the  richness  and  bactericidal  power  of  the 
blood ;  it  stimulates  leucocytosis,  and  helps  to  replace  the  waste  of 
muscular  tissue  which  is  such  a  marked  feature  in  phthisis.  Bards- 
well  and  Chapman,  who  have  made  a  special  study  of  the  dietetics  of 
phthisis,  recomnrend  for  a  phthisical  male  patient  who  is  not  doing  any 
work  a  diet  containing  about  150  grammes  of  protein,  150  grammes 
of  fat,  and  250  grammes  of  carbohydrate,  with  a  Calorie  value  of  3,000. 

For  women  the  standard  should  be  somewhat  lower,  viz.,  protein 
126  grammes,  fat  150  grammes,  carbohydrate  220  grammes,  with  a 
Calorie  value  of  2,814.  The  following  actual  diets  conform  to 
these  standards : 


Article  of  Food  as  Served. 


Milk         

Bread        

Porridge 

Butter 

Breakfast  meat,  such  as  bacon,  fish, 

etc 

Ordinary  meat    ..         ..         .. 

Pudding ..         .. 

Vegetables  


Amount  Prescribed. 


For  Men. 


1500  C.C. 
180  grammes. 
120        ,, 
45        M 

30        ,. 

180        „ 
300        „ 
qs. 


For  Women. 


1500  CO. 

135  grammes. 
120        ,, 
45         •• 

30 

150         >> 
180         „ 
q.s. 


*  Lancet,  1864,  i.  432. 

'  See  Forbes  Ross,  '  Meat  Albumin  Dietary  in  the  Treatment  of  Tuberculosis,' 
Brit.  Med.  Journ.,  1901,  ii.  io6i  ;  Bardswell,  Goodbody,  and  Chapman,  'On 
the  Effects  of  Forced  Feeding  in  Cases  of  Pulmonary  Tuberculosis,"  etc.,  ibid., 
1902,  i.  449  ;  'Dietetics  in  Tuberculosis,'  Proceedings  of  the  Royal  Society,  B., 
Ixxx.  151  ;  Galbraith,  '  The  Dietetic  Treatment  of  Pulmonary  Tuberculosis 
from  the  Point  of  View  of  its  Hsematology  and  flistopathology,'  ibid.,  March  14, 
1903;  and  Lloyd  Smith,  '  Diet  in  Phthisis,'  Lancet,  1903,  ii.  1015. 


DIET  IN  TUBERCULOSIS  515 

The  exact  amount  and  constitution  of  the  diet  in  each  case  should 
be  fixed  after  due  consideration  has  been  given  to  the  activity  and 
extent  of  the  disease,  the  amount  to  which  the  patient's  weight  is 
below  his  normal,  his  digestive  capacity,  and,  to  some  extent,  his 
personal  dietetic  likes  and  dislikes,  but  one  should  aim  at  making 
good  lost  weight  at  the  rate  of  i  to  2  pounds  per  week.  When  the 
patient  has  once  regained  his  normal  weight  or  a  little  more,  the  diet 
should  be  reconstructed  more  upon  the  lines  of  what  would  be 
suitable  for  the  same  person  in  perfect  health,  and  if  active  exercise 
or  muscular  work  is  being  performed,  the  amount  of  fat  and  carbo- 
hydrate in  the  diet  should  be  increased. 

Anorexia  in  phthisis  is  to  be  met  by  a  change  in  hygienic  surround- 
ings, by  the  use  of  bitters,  by  frequently  varying  the  menu,  by  giving 
the  food  in  a  more  fluid  form,  and  by  eliminating  the  more  bulky  and 
less  nutritive  articles — e.g.,  porridge,  green  vegetables,  etc.  The 
necessary  protein  in  such  circumstances  can  be  got  in  by  fortifying 
fluid  foods  with  one  of  the  soluble  casein  preparations  or  by  adding 
it  to  puddings ;  fat  can  be  taken  in  the  form  of  cream  and  sugar  as 
grape  sugar,  lactose,  lemonade,  etc. 

When  fever  exists,  the  food  should  be  given  as  far  as  possible  in 
apyrexial  intervals  or  after  the  temperature  has  been  artificially 
reduced  by  sponging.  If  the  digestive  power  is  good,  an  effort 
should  be  made  to  maintain  the  standard  diet  in  spite  of  the  fever, 
but  if  this  proves  impossible,  the  diet  must  be  constructed  on  the 
same  lines  as  for  anorexia. 

The  method  of  feeding  up  neurasthenic  patients  has  become  widely 
known  under  the  title  of  the  Weir  Mitchell  Treatment  or  Rest  Cure. 
The  general  management  of  such  cases  cannot  be  fully  described 
here,  but  some  points  connected  with  the  diet  which  form  so 
important  a  part  of  the  plan  must  be  mentioned. 

It  is  usual  to  begin  with  milk  alone,  given  quite  fresh  and 
perfectly  skimmed.  The  milk  should  be  sipped  slowly,  it  should  be 
warm,  and  from  40  to  80  ounces  should  be  given  daily  in  equal 
quantities  every  two  hours.  Various  methods  of  varying  the  flavour 
of  the  milk  are  described  on  p.  131.  After  two  or  three  days,  some 
of  the  milk  may  be  thickened  with  farinaceous  foods  (arrowroot, 
cornflour,  groats,  one  of  the  numerous  patent  preparations,  etc.),  and 
as  digestive  power  improves,  lightly  cooked  eggs,  underdone  meat, 
fish,  chicken,  game,  sieved  potato,  and  bread-and-butter  may  be 
gradually  added  until  the  patient  is  taking  three  large  meals  a  day 
with  from  3  to  5  pints  of  milk  and  perhaps  a  gill  of  cream  and  an 


5i6  FOOD  AND  DIETETICS 

ounce  of  malt  extract  in  addition.  The  total  fuel  value  of  such  a 
diet  may  in  some  cases  exceed  10,000  Calories. 

The  food  should  be  plain,  appetizing,  and  well  cooked,  the  chief 
meal  being  in  the  middle  of  the  day,  while  the  evening  one  is  lighter. 
Part  of  the  milk  may  be  taken  with  the  meals,  the  rest  between  them. 

In  all  cases  in  which  a  large  amount  of  food  is  being  administered, 
the  use  of  alcohol,  in  some  form  or  another,  will  often  be  found  a 
great  help.  Especially  is  this  the  case  when  the  diet  is  very  rich  in 
fat.  The  safest  guide  to  its  use  is  the  state  of  the  appetite  and 
digestion.  Where  these  are  improved  by  its  administration,  it  does 
good.  The  form  to  be  selected  is  largely  a  matter  of  taste,  but  a 
sound  red  wine,  such  as  burgundy,  is  perhaps  most  generally  useful, 
or,  if  a  malt  liquor  be  preferred,  good  bottled  stout 

The  Dietetics  of  Gout.^ 

Unfortunately,  chemical  pathology  is  not  yet  in  a  position  to 
furnish  us  with  very  clear  indications  as  to  the  best  diet  for  the 
gouty.  In  spite  of  all  the  work  which  has  been  done  upon  the 
subject,  we  are  still,  it  must  be  confessed,  very  much  in  the  dark  as 
to  the  relations  of  uric  acid  to  general  metabolism  and  to  the  gouty 
state.  It  is  becoming  more  and  more  clear,  however,  that,  in 
mammals  at  least,  uric  acid  is  derived  mainly,  if  not  entirely,  from 
the  decomposition  of  nucleins  either  contained  as  such  in  the 
food,  or  produced  by  the  disintegration  of  the  body  cells.  Uric 
acid  from  the  first  of  these  sources  may  be  conveniently  described 
as  'exogenous  uric  acid,'  while  the  fraction  produced  in  the  body 
may  be  designated  as  '  endogenous.* 

While  the  nucleins  of  the  food  are  the  main,  they  are  not  the 
exclusive,  source  of  the  exogenous  uric  acid.  Part  of  it  is  also 
derived  from  such  substances  as  caffeine  and  from  free  'purins' 
contained  in  the  food.  Further,  the  whole  of  the  uric  acid  derived 
from  the  food  does  not  appear  in  the  urine  as  such.  Part  of  it  is 
converted  in  the  body  into  urea  and  other  compounds.  The  fraction 
so  changed  varies  from  one-quarter  to  one-half  of  the  total  possible 
yield,  but  the  amount  is  very  constant  for  different  foods,  and  appears 
to  vary  but  little  in  different  individuals. 

The  chief  fluctuations  in  the  amount  of  uric  acid  in  the  urine  can  be 
explained  by  variations  in  the  amount  of  uric  acid  yielders  (purins)  con- 
tained in  the  food ;  the  endogenous  fraction,  on  the  other  hand,  seems 
to  be  remarkably  fixed,  but  as  to  its  exact  seat  and  mode  of  formation, 
and  the  conditions  which  control  it,  we  have  still  much  to  learn. 

^  For  a  full  discussion  of  this  vexed  question,  see  a  paper  by  A.  E.  Garrod 
('  The  Dietetic  Treatment  of  Gout '),  Lancet,  June  28,  IQ13. 


DIET  IN  GOUT  517 

Those  who  believe  that  uric  acid  is  the  fans  et  origo  of  the  gouty 
state  have  therefore  concentrated  their  attention  upon  Hmiting  the 
intake  of  uric  acid  formers  in  the  food,  and  recommend  the  adoption 
of  a  *  purin-free '  diet.  Such  a  diet  is  described  in  detail  elsewhere 
(P-  55i)»  but  the  writer  would  only  say  here  that,  although  it  un- 
doubtedly gives  good  results  in  some  gouty  persons,  it  is  by  no 
means  suited  to  all,  as  its  prolonged  use  is  apt  to  lead  to  impairment 
of  the  general  health,  and  particularly  of  the  digestive  capacity. 

Nothing  is  more  certain,  moreover,  than  that  a  patient  may  still 
suffer  from  gout,  even  although  the  substances  capable  of  yielding 
uric  acid  are  reduced  in  the  diet  to  a  minimum.  For  we  have  still  the 
endogenous  production  of  uric  acid  to  deal  with,  and  about  the  influence 
of  diet  on  such  production  we  know  almost  nothing.  Nor  does  accu- 
mulated clinical  experience  afford  as  much  help  as  one  might  expect, 
for  the  opinions  of  different  writers  on  the  subject,  as  so  often  happens, 
are  exceedingly  conflicting,  and  a  system  which  suits  one  patient  does 
not  necessarily  agree  with  another.  On  the  whole,  the  belief  seems  to 
be  gaining  ground  that  quantity  must  be  attended  to  quite  as  much 
as  quality,  and  that  the  best  diet  for  the  gouty  is  a  spare  one,  com- 
posed of  simple  ingredients,  containing  only  a  moderate  amount  of 
carbohydrate  and  fat,  and  in  which  not  too  much  of  the  protein  is 
derived  from  animal  sources.  In  the  light  of  the  above  facts,  it 
might  be  well  to  add  that,  so  far  as  is  compatible  with  healthy 
nutrition,  the  animal  ingredients  should  consist  mainly  of  milk  and 
eggs  ;  certainly  meat  should  not  be  taken  oftener  than  once  a  day. 

The  dietary  usually  prescribed  for  gouty  patients  at  Carlsbad  is 
based  upon  these  principles,  and  is  as  follows^ :  Breakfast :  weak  tea 
with  cream,  biscuits  (2  to  4  ounces),  butter  (^  ounce),  two  soft- 
boiled  eggs.  Dinner :  soup,  either  clear  or  with  pearl  barley  or  rice 
(i  ounce) ;  fish — trout,  pike,  or  perch  (3^  ounces) — with  melted  butter, 
lemon-juice,  and  potatoes  (2  ounces) ;  roast  veal  (3^  ounces)  or 
mutton  cutlets  or  roast  fowl,  spinach,  cheese  (i  ounce),  stewed 
fruit  (3I  ounces),  bread  (5  ounces).  Supper:  soup  or  milk  or  weak 
tea  with  milk,  biscuits,  lean  bacon,  or  one  or  two  eggs,  jam.  Beverage 
at  dinner  and  supper:  water,  mineral  water,  |  pint  of  light  claret 
with  water  or  two  tablespoonfuls  of  whisky  with  a  half-bottle  of 
mineral  water. 

It  is  important  to  remember,  however,  that  there  is  no  routine  plan 

which  is  suitable  in  all  cases.    The  state  of  the  patient's  nutrition  and 

digestive  and  excretory  organs  may  necessitate  modifications  of  the 

diet  in  various  directions,  as  may  also  the  presence  of  complications. 

*  'The  Treatment  of  Gout  in  Carlsbad,'  by  Dr.  B.  London  {Practitioner, 
1903,  Ixxi.  161.  320}. 


5i8  FOOD  AND  DIETETICS 

Beverages  in  Gout. 

What  he  drinks  is,  to  the  gouty  man,  quite  as  important  as  what 
he  eats.  Tea,  coffee  and  cocoa  are  certainly  sources  of  uric  acid, 
and  may  therefore  require  to  be  avoided.  Experience  also  shows 
that  the  free  consumption  of  alcohol  is  harmful,  and,  if  possible,  the 
patient  should  try  to  live  without  it.  Too  often,  however,  this  is  a 
counsel  of  perfection,  and  in  that  case  a  sound  natural  wine,  which 
may  be  taken  with  some  alkaline  mineral  water,  is  the  best  beverage 
to  select.  The  stronger  wines  are  dangerous,  both  on  account  of 
the  large  proportion  of  alcohol  which  they  possess,  and  also  because 
they  are  apt  to  contain  sugar,  which  is  prone  to  excite  dyspepsia  in 
the  gouty,  even  if  it  has — a  point  which  is  still  sub  judtce — no  influence 
on  the  production  of  uric  acid  itself.  Champagne  is  also  injurious, 
and  so,  too,  is  bottled  cider,  though  '  rough  '  cider  and  dry  sherry 
usually  agree  well.  It  is  the  fashion  to  recommend  whisky  to  gouty 
people,  and  to  this  course  there  can  be  no  objection,  provided  it  be 
taken  well  diluted,  and  the  quantity  limited  to  2  ounces  a  day.  It  is 
certainly  a  useful  resource  in  cases  in  which  the  natural  wines 
disagree. 

On  the  whole,  however,  it  must  be  admitted  that  there  is  no 
better  beverage  for  gouty  people  than  plain  water,  and  they  should 
be  encouraged  to  drink  largely  of  it,  as  an  admirable  aid  to  the 
elimination  of  nitrogenous  waste. 

Plan  of  Diet  in  Gout. 

In  view  of  the  principles  discussed  above,  the  general  directions 
for  the  diet  in  a  case  of  chronic  gout  may  be  summed  up  as  follows : 

GENERAL  RULES. 
Meals  should  be  as  simple  as  possible. 
Butcher's  meat  should  only  be  eaten  once  a  day,  and  in  a  very  moderate 

amount. 
Sugar  and  sweets  should  be  taken  sparingly. 
Bread  should  be  taken  in  the  form  of  crisp  toast  or  rusks. 
Raw  fruit  should  never  be  taken  at  a  meat  meal,  and  is  best  consumed  early 

in  the  day. 
If  alcohol  is  necessary,  it  should   be  taken  only  in   the  form  of  brandy, 

whisky,  or  a  light  still  Moselle. 

Articles  to  be  Avoided. 

1.  Rich  meat-soups:  Oxtail,  turtle,  mock  turtle,  kidney,  mulligatawny,  hare, 

giblet. 

2.  Salmon,  mackerel,  eels,  lobster,  crab,  mussel,  salted  fish,  preserved  fish, 

smoked  fish,  tinned  fish. 

3.  Duck,  goose,  pigeon,  high  game. 

4.  Meats  cooked  a  second  time.  Hare,  venison,  pork,  lean  ham,  sweetbreads, 

liver,  kidney,  salted  corned  or  cured  meats,  pickled  meats,  preserved 
and  potted  meats,  sausages  ;  all  articles  of  food  pickled  in  vinegar ;  all 
highly  seasoned  dishes  and  rich  sauces. 


DIET  IN  GOUT  519 

5.  Tomatoes,  beetroot,  cucumber,  asparagus,  rhubarb,  onions,  mushrooms 

truffles. 

6.  Peas,  beans,  lentils  and  oatmeal. 

7.  Rich  pastry,  rich  sweets,  new  bread,  cakes,  nuts,  dried  fruits,  ices,  ice 

cream. 

Scheme  of  Diet. 

Half  a  pint  of  hot  water  (flavoured,  if  desired,  with  a  slice  of  lemon  peel) 
should  be  slowly  sipped  immediately  on  rising,  and  again  just  before 
retiring  to  bed. 

Breakfast. 

A  selection  may  be  made  from  the  following  articles :  Whiting,  sole  or 
plaice,  fat  bacon,  lightly  cooked  eggs,  dry  toast  thinly  buttered,  tea 
infused  for  three  minutes  and  then  strained  from  the  leaves. 

Luncheon  and  Dinner. 
Any  clear  soup. 
White  fish  (except  those  forbidden  above),  chicken,  pheasant,  turkey  or 

game  (not  high). 
Butcher's  meat  (in  accordance  with  the  limitations  already  indicated). 
One  of  the  following  vegetables  :  Spinach,  Brussels  sprouts,  French  beans, 

winter  cabbage,  savoy  cabbage,  turnip  tops,  turnips,  celery,  potatoes  in 

moderate  quantity  (but  not  new  potatoes). 
Stewed  fresh  fruit. 

Salads  of  green  vegetables  are  permissible,  but  only  with  simple  dressings. 
Savouries  are  usually  best  avoided,  but  a  morsel  of  cheese  may  be  taken  if 

free  from  mould. 

Rheumatoid  Arthritis,  Osteo-Arthritis  and  Fibrositis. 

There  is  no  necessity  for  any  restrictions  of  diet  in  rheumatoid 
arthritis ;  on  the  contrary,  an  abundant  and  nourishing  mixed  diet 
is  a  most  important  part  of  the  treatment,  and  the  use  of  alcoholic 
beverages  in  moderation  is  permissible  and  sometimes  advantageous. 
The  old  term  '  rheumatic  gout'  has  been  responsible  for  much  harm 
done  to  these  patients,  for  it  has  often  led  to  their  being  put  on  a 
restricted  diet  under  the  belief  that  their  disease  was  in  some  way 
related  to  gout,  and  required  the  same  sort  of  diet. 

In  osteo-arthritis  no  special  dietetic  treatment  is  called  for  unless, 
as  is  often  the  case,  the  patient  is  also  corpulent.  In  such  circum- 
stances the  diet  should  be  directed  to  the  treatment  of  the  obesity 
on  the  lines  already  described. 

The  relation  of  diet  io  fibrositis  is  not  clearly  understood,  but  many 
believe  that  it  is  a  condition  associated  with  increased  intestinal 
fermentation  and  decomposition.  On  the  whole,  the  dietetic  rules 
should  follow  those  for  gout,  but  individual  peculiarities  should 
always  be  taken  into  account. 

Gravel. 

The  rational  indications  in  the  treatment  of  gravel  would  appear 
to  be  two  in  number:  (i)  To  diminish  the  amount  of  uric  acid 
which  the  urine  contains ;  (2)  to  increase  its  solubility. 


'520  FOOD  AND  DIETETICS 

The  former  of  these  indications  can  be  fulfilled,  as  far  as  the 
exogenous  fraction  of  the  urinary  acid  is  concerned,  by  a  diminution 
of  the  amount  of  uric  acid  yielders  in  the  diet.  We  have  already 
seen  what  are  the  best  foods  to  select  for  that  purpose.  As  regards 
diminishing  that  part  of  the  uric  acid  which  is  formed  in  the  body 
itself,  we  are  just  as  much  at  a  loss  as  in  the  case  of  gout.  Some 
authorities  pin  their  faith  to  a  diminution  of  the  protein-sparers — i.e., 
carbohydrates  and  fat— in  the  food.  It  is  possible  that  this  may 
favour  the  conversion  of  uric  acid  into  urea,  though  it  must  be 
admitted  that  such  a  view  is  as  yet  very  far  from  being  proved. 
At  all  events,  this  plan  commended  itself  to  such  an  experienced 
observer  as  Sir  Henry  Thompson. 

He  recommends^  that  the  diet  should  consist  of  white  fish,  poultry, 
game,  lean  meat,  unsweetened  jellies,  bread,  cereals,  pulses,  green 
vegetables  and  apples,  but  no  sweet  fruits.  A  little  butter  may  be 
taken,  and  milk  in  moderation.  The  things  to  avoid  are  cream, 
eggs,  cheese,  pastry,  pork  and  other  fat  meats,  the  fatter  kinds  of 
fish,  suet,  much  milk  or  butter,  and  all  substances  containing  sugar. 
He  advises  that  farinaceous  foods  should  be  mixed  with  light  broths 
instead  of  milk,  and  flavoured  with  some  condiment,  such  as  a  pinch 
of  curry  or  a  morsel  of  chutney,  instead  of  sugar. 

On  the  other  hand,  Goodhart,^  after  menti(5ning  the  case  of  a 
patient  who  suifered  from  gravel  when  on  a  m'ilk  diet,  but  got  quit 
of  it  on  changing  to  meat  and  port  wine,  says :  '  I  have  come  to  be 
certain  that  in  the  majority  of  cases  of  uric  acidity  it  is  not  a  question 
of  diet  at  all !' 

The  second  indication  mentioned  above — that  of  increasing  the 
solubility  of  uric  acid  in  the  urine — can  be  accomplished  by  rendering 
the  urine  less  acid.  As  Sir  William  Roberts  has  said,^  the  deposition 
of  uric  acid  from  an  alkaline  urine  is  a  chemical  impossibility.  Now, 
we  can  certainly  render  the  urine  less  acid  by  the  free  use  of  green 
vegetables  and  other  foods  containing  alkaline  salts  of  potash,  but 
the  same  object  can  be  accomplished  so  much  more  certainly  anc^ 
simply  by  the  aid  of  drugs  that  the  dietetic  means  at  our  disposal 
are  hardly  worth  considering.  The  other  factors  concerned  in 
keeping  uric  acid  in  solution  are  the  presence  of  urea  and  mineral 
salts.  An  increase  in  these  hinders  the  separation  out  of  uric  acid. 
For  that  reason  it  may  be  well  that  the  diet  should  not  be  too  poor 
in  proteins,  and  that  it  should  contain  an  abundance  of  common  salt. 

>  '  Diseases  of  the  Urinary  Organs,'  8th  edit.,  lecture  xxv. 
'  An  address  on  '  Acidity,'  Lancet,  1900,  i.  i. 
•  Croonian  Lectures,  1892. 


TREATMENT  OF  SCURVY  521 

As  regards  the  question  of  beverages  in  gravel,  the  same  remarks 
apply  as  in  the  case  of  gout. 


OXALURIA.I 

In  cases  in  which  much  oxalate  of  lime  is  separating  out  in  the 
urine,  one  should  select  a  diet  which  contains  little  oxalic  acid  and 
lime  and  plenty  of  magnesia,  for  the  latter  favours  the  solution  of 
calcium  oxalate.  In  order  to  meet  the  former  indication,  foods  rich 
in  oxalic  acid  should  be  avoided  {e.g.,  spinach,  rhubarb,  tea,  etc. 
See  table  on  p.  297),  and  also  those  which  contain  much  calcium 
(e.g.,  milk,  egg,  fresh  vegetables.  See  p.  290),  whilst  the  latter 
indication  is  met  by  the  use  of  such  foods  as  meat,  cereals,  bread, 
rice,  peas,  potatoes,  apples,  coffee,  and  beer. 

Dietetic  Treatment  of  Scurvy. 

Whatever  view  may  be  held  as  to  the  exact  causation  of  scurvy, 
ail  experience  goes  to  show  that  the  introduction  into  the  diet  of  a 
sufficient  quantity  of  fresh  vegetable  food  has  a  powerfully  curative 
effiect  in  this  disease.  It  would  further  appear  that  there  is  no 
particular  form  of  vegetable  food  which  is  possessed  of  any  specific 
influence  over  the  complaint,  but  that  all  are  about  equally  efficacious. 
The  antiscorbutic  power  of  fresh  limes  and  lemons  has  been  known 
since  the  seventeenth  century,  and  these  fruits  still  constitute  the 
favourite  remedy  for  the  disease.  It  is  important,  however,  that 
they  should  be  fresh.  Lime-juice  which  has  been  stored  for  a  long 
time  is  apt  to  decompose  into  citric  acid  and  carbonates,  and  thereby 
loses  much  of  its  value.  An  objection  to  lime-juice  is  its  acrid  taste, 
by  reason  of  which  it  is  sometimes  found  to  be  difficult  to  induce 
those  who  are  exposed  to  the  disease  to  take  the  juice  regularly  as 
a  preventive.  Lemonade  made  from  fresh  lemons  is  not  open  to 
this  objection.  Preserved  vegetables,  though  of  undoubted  utility, 
appear  to  have  a  feebler  antiscorbutic  power  than  fresh.  Sauer- 
kraut is  the  most  serviceable  of  preserved  vegetables,  and  Captain 
Cook  employed  it  with  success  in  some  of  his  voyages. 

Infusion  of  malt  is  another  powerful  antiscorbutic.  Forster,^  who 
accompanied  Coc^  in  his  second  voyage,  describes  a  severe  outbreak 
of  scurvy  and  its  cure  by  infusion  of  malt  without  any  other  change 
in  the  diet.  He  adds :  *  The  encomiums  on  the  efficacy  of  malt  cannot 
be  exaggerated.*     Some  of  the  worst  cases  he  saw  took  as  much  as 

1  See  Klemperer  and  Tritschler,  Zeit.  f.  Klin.  Med.,  1902,  xliv.  337. 

"  •  Notes  from  a  Voyage  Round  the  World,"  by  George  Forster,  vol.  i..  1777, 


522  FOOD  AND  DIETETICS 

5  pints  of  the  infusion  per  day.  Here,  again,  it  is  important  that 
the  malt  should  be  fresh,  for  its  properties  are  impaired  if  it  is 
allowed  to  become  damp  and  mouldy. 

Fresh  meat  juice  is  of  undoubted  value  as  a  remedy  for  scurvy, 
and  so,  also,  is  milk. 

Of  beverages,  French  and  Italian  wines  are  admitted  to  possess 
antiscorbutic  properties  ;  but  opinions  regarding  the  value  of  cider 
in  this  respect  vary  considerably. 

Dietetic  Treatment  of  Infantile  Scurvy. 

The  treatment  of  infantile  scurvy  is  purely  dietetic.  The  use  of 
tinned  foods  and  boiled  or  sterilized  milk  must  at  once  be  stopped, 
and  the  child  put  upon  a  due  allowance  of  fresh  milk.  Fruit  juice 
should  be  added  to  the  diet,  a  few  teaspoonfuls  of  grape  or  orange 
juice,  sweetened,  if  necessary,  with  a  little  sugar,  being  given  every 
day.  Fresh  raw-meat  juice  is  also  of  value,  and  may  be  given  in 
quantities  of  ^  ounce  daily.  Baked  potato,  too,  owing  to  its  rich- 
ness in  potash  salts,  is  of  great  service.  It  may  be  rubbed  up 
with  the  milk  into  a  thin  cream  and  given  through  the  bottle. 

Dietetic  Treatment  of  Rickets. 

Whatever  the  exact  pathology  of  rickets  may  be,  there  can  be  no 
doubt  that  one  of  the  main  factors  in  its  production  is  an  unsuitable 
diet.  The  diet  may  be  either  altogether  deficient  in  nutritive 
properties  or,  more  commonly,  it  is  merely  an  ill-balanced  one,  in 
which  the  carbohydrate  constituents  are  in  relative  excess  when 
compared  with  the  proteins  and  fats.  The  first  step  in  treatment, 
therefore,  is,  in  most  cases,  to  decrease  the  starchy  and  sugary  com- 
ponents of  the  food,  and  to  increase  the  proteins  and  fats.  With 
this  object  in  view  the  use  of  all  purely  starchy  foods — e.g.,  sago, 
tapioca,  and  arrowroot,  should  he  discontinued,  and  the  same  is  true 
of  patent  and  proprietary  infant  foods,  most  of  which  contain  an 
excess  of  carbohydrates.  On  the  other  hand,  the  amount  of  pure 
cow's  milk  in  the  diet  usually  needs  to  be  increased,  and  fats  should 
be  given  liberally  in  the  form  of  cream,  bacon  fat,  and  butter. 
The  use  of  condensed  milk  must  be  rigidly  prohibited,  as  it  is 
not  only  poor  in  fat,  but,  in  most  cases,  contains  a  considerable 
excess  of  sugar.  The  nitrogenous  constituents  may  be  further 
supplemented  by  the  use  of  raw  beef -juice,  scraped  meat,  or  strong 
beef-tea. 

Yolk  of  egg  is  also  a  valuable  food  for  rickety  children,  containing, 


DIET  IN  DISORDERS  OF  THE  STOMACH         523 

as  it  does,  not  only  protein  and  fat,  but  valuable  organic  compounds 
of  phosphorus  and  iron,  both  of  which  elements  the  rickety  patient 
needs.  It  may  be  given  either  in  the  raw  state  mixed  with  milk  or 
very  lightly  boiled,  and  is  usually  well  borne,  even  before  the  child 
is  a  year  old. 

Oat  flour  and  whole  wheat  flour  may  be  used  in  moderate 
quantities  to  thicken  some  of  the  milk,  the  former  being,  perhaps, 
specially  useful  in  virtue  of  the  fat,  iron  and  phosphorus  in  which  it 
is  so  rich. 

3.  Diet  in  Disorders  of  the  Stomach. 

General  Considerations. 

Seeing  that  the  essential  role  of  the  stomach  is  a  mechanical  rather 
than  a  truly  digestive  one,  the  physical  form  of  the  food  must  always 
be  of  more  importance  in  dyspepsia  than  its  chemical  composition. 
In  proof  of  this,  one  finds  that  so  long  as  the  stomach  is  able  to  pass 
the  food  on  into  the  intestine  absorption  and  nutrition  go  on  without 
impairment,  even  although  the  digestive  juices  of  the  stomach  itself 
are  no  longer  present.^  The  first  rule  to  be  observed,  therefore,  in 
drawing  up  a  dietary  for  disorders  of  the  stomach,  is  to  see  that  the 
food  is  presented  in  such  a  form  that  the  stomach  has  but  little 
difficulty  in  driving  it  en  into  the  duodenum.  In  practice  this  means 
that  the  food  must  be  in  a  fine  state  of  division,  and  should  be  care- 
fully chewed. 

The  question  of  bulk  must  also  be  considered.  The  larger  the 
mass  of  the  food,  the  greater  is  the  muscular  labour  imposed  on  the 
stomach.  It  is  probably  on  this  account  that  animal  foods  are,  as  a 
class,  less  troublesome  to  most  dyspeptics  than  vegetable  products. 
For  the  same  reason,  the  meals  in  dyspepsia  should  be  of  small  size, 
but  taken  at  rather  short  intervals. 

As  regards  the  behaviour  of  the  dyspeptic  stomach  to  the  diff"erent 
chemical  ingredients  of  the  food,  great  individual  differences  exist, 
and  in  no  class  of  case  is  it  more  important  to  study  the  question 
of  idiosyncrasy.  In  a  majority  of  instances,  however,  one  finds  that 
fat  is  more  apt  to  give  offence  than  any  other  constituent.  This  is 
particularly  true  of  cooked  fat,  probably  because  in  process  of  cook- 
ing fatty  acids,  acrolein,  and  other  irritating  substances,  are  apt  to 
be  liberated.  On  the  other  hand,  butter  and  bacon-fat  can  usually 
be  managed  with  but  little  difficulty. 

^  See  Von  Noorden,  '  Ueber  den  Stoffwechsel  der  Magen  Kranken  und  Seine 
Anspriache  an  die  Therapie, '  Berliner  Klinik,  1893,  Hft.  55,  1-19,  and  the  same 
author,  Z«V.  /.  Klin  Med.,  1890,  xvii.  137;  also  Moritz,  Mimck.  Med.  Woch,, 
1893.  xl-  75- 


524  FOOD  AND  DIETETICS 

We  may  now  pass  to  the  more  detailed  consideration  of  the  dietetic 
treatment  suitable  in  different  forms  of  gastric  disorder,  leaving  the 
discussion  of  some  further  general  principles  until  we  come  to  speak 
of  '  functional '  dyspepsias.  In  handling  the  subject  it  will  be  well 
to  take  up  first  those  diseases  of  the  stomach  which  are  accompanied 
by  definite  organic  change,  and  afterwards  to  consider  the  so-called 
'  functional '  disorders  in  one  group.  Such  an  arrangement  is 
admittedly  unscientific,  but  it  has  the  advantage  of  practical  con- 
venience, and  our  knowledge  does  not  at  present  admit  of  any  more 
satisfactory  system  of  classification. 

Gastric  Ulcer. 

Ever  since  Cruveilhier  clearly  enunciated  it,  the  principle  has  been 
accepted  by  all  writers  that  rest  for  the  organ  is  the  point  chiefly  to 
be  aimed  at  La  arranging  a  diet  for  cases  of  gastric  ulcer,  and  rest 
may  be  taken  to  mean  the  protection  of  the  mucous  membrane  from 
both  mechanical  and  chemical  irritants. 

In  very  severe  cases,  and  especially  if  there  has  been  recent 
bleeding,  rest  must  be  absolute.  This  is  accomplished  by  cutting  off" 
all  nourishment  by  the  mouth,  and  feeding  the  patient  exclusively 
per  rectum.  Many  cases  have  been  treated  in  this  way  for  periods 
of  even  twenty  days  at  a  time,^  but  it  is  rarely  necessary  to  continue 
the  injections  for  more  than  three  days.  The  details  of  such  treat- 
ment will  be  considered  in  the  last  chapter. 

After  the  period  of  rectal  feeding,  if  all  pain  and  vomiting  have 
ceased,  and  in  less  severe  cases  from  the  outset,  one  can  begin  to 
feel  one's  way  in  giving  food  by  the  mouth.  At  first  the  diet  must  be 
strictly  fluid,  consisting  of  milk,  diluted  with  lime  or  barley-water, 
or  peptonized,  given  in  quantities  of  about  5  ounces  every  hour,  and 
at  the  body  temperature.  Small  feeds  of  beef-tea  may  be  given 
occasionally  as  a  change. 

After  another  week,  if  all  is  going  well,  one  may  advance  to  semi- 
fluid diet,  the  milk  and  beef-tea  being  thickened  with  a  little  corn- 
flour, arrowroot,  fine  oat  flour,  or  biscuit  powder.  Some  of  the 
patent  predigested  cereal  foods  are  useful  at  this  stage,  and  lightly 
cooked  eggs  are  also  permissible.  The  Leube-Rosenthal  Meat 
Solution  is  also  well  borne  as  a  rule,  or  one  may  substitute  for  it 
well-made  *  whole  beef-tea,'  or  a  little  of  one  of  the  patent  protein 

1  See  '  Traitement  de  certaines  Maladies  de  I'Estomac  par  la  Cure  de  Repos 
absolu  et  prolonge  avec  Alimentatioa  rectale  exclusive,'  Dr.  A.  P.  Gros.  Paris* 
BaiUiere  et  Fils,  1898. 


GASTRIC  ULCER  523 

foods  (Plasmon,  etc.)  may  be  given  stirred  into  clear  broth  or  in  com- 
bination with  arrowroot.  Peptonized  milk  gruel  is  also  very  helpful 
at  this  period. 

After  the  lapse  of  another  week  one  may  add  a  little  stale  bread 
and  butter,  sweetbread  or  white  fish,  potato  puree  and  custard,  and 
gradually  advance  to  underdone  mutton,  milk  pudding,  spinach  and 
cauliflower,  and  from  this  to  ordinary  plain  unirritating  food  (see 
Chronic  Gastritis). 

Any  recrudescence  of  symptoms  must  be  the  signal  for  immediately 
retracing  one's  steps  and  reducing  the  diet,  and  even  when  con- 
valescence is  fairly  established  the  patient  must  be  careful  for  a  long 
time  to  avoid  all  irritating  and  indigestible  forms  of  food,  and  very 
hot  or  very  cold  articles. 

The  above  may  be  described  as  the  classical  method  of  dieting 
cases  of  gastric  ulcer,  although  some  of  the  details  have  varied  in 
the  hands  of  different  physicians.  In  recent  times,  however, 
Lenhartz  has  introduced  a  very  different  plan  of  diet  which  now 
goes  by  his  name,  and  has  been  widely  adopted.  The  guiding 
principles  of  the  Lenhartz  diet  are  these  :  (i)  To  promote  healing  of 
the  ulcer  by  giving  as  much  nourishmg  food  as  possible  ;  (2)  to  '  fix ' 
the  acid  of  the  gastric  juice,  and  so  prevent  its  interfering  with 
healing  by  ensuring  that  the  food  contains  a  large  proportion  of 
protein  ;  (3)  to  prevent  distension  of  the  stomach  by  the  use  of  small 
feeds. 

The  method  is  carried  out  as  follows  :^  The  patient  is  kept 
absolutely  in  bed  for  four  weeks,  for  the  first  two  of  which  he  is 
not  allowed  to  move  from  the  supine  position  for  any  reason  what- 
ever. All  mental  excitement  must  be  avoided.  An  icebag  is  kept 
upon  the  stomach  almost  continually  for  the  first  two  weeks.  The 
dietary  consists  of  eggs  beaten  up  with  sugar,  or  in  some  cases  with 
wine,  and  iced  ;  and  of  milk.  These  two  foods  are  taken  in  small 
quantities  at  frequent  intervals  from  a  teaspoon,  the  quantity  pre- 
scribed being  spread  over  the  day,  and  not  given  at  definite  meal- 
times. The  first  day  7  to  10  ounces  of  milk  are  given  and  one  egg. 
The  quantity  is  increased  daily  by  3^  ounces  of  milk  and  one  egg 
until  if  pints  of  milk  and  six  eggs,  or  in  some  cases  eight  eggs,  are 
reached.  From  about  the  third  to  the  eighth  day  raw  or  almost  raw 
mince  is  added,  starting  with  an  ounce  in  divided  doses,  either  beaten 
up  with  the  egg  or  alone ;  the  next  day,  if  the  mince  is  well  borne, 
2  ounces  are  given  ;  minced  beef  may  be  used. 

*  Spriggs,  Brit.  Med.  Journ.,  1909,  i.  825. 


52«  FOOD  AND  DIETETICS 

Food  is  given  at  first  at  hourly  intervals  from  7  a.m.  to  9  p.m.,  but 
complete  rest  is  allowed  at  night.  Both  the  eggs  and  milk  are  iced 
and  the  eggs  beaten  up  whole.  Granulated  sugar  is  added  to  the 
eggs  on  the  third  day.  Some  soluble  casein  preparation  (Plasmon, 
Casumen,  Sanatogen,  etc.)  may  be  used  instead  of  the  raw  mince. 

From  the  seventh  to  the  eighth  day  boiled  rice  is  added,  followed 
by  softened  bread,  and  later  by  a  small  quantity  of  bread  and  butter. 
One  or  more  eggs  may  now  be  lightly  boiled.  The  diet  is  then 
gradually  increased  by  the  addition  of  mince  or  pounded  fish,  with  a 
corresponding  reduction  of  eggs,  until  by  the  end  of  the  fourth  week 
the  patient  is  on  an  ordinary  mixed  diet  containing  the  common 
foodstuffs,  with  the  exception  of  indigestible  solids,  such  as  peas  or 
other  seeds.  The  patient  is  instructed  to  masticate  very  slowly. 
On  the  twenty-eighth  day  the  patient  is  allowed  to  get  up,  and  dis- 
charged from  the  sixth  to  the  tenth  week. 

Lenhartz^  claims  that  under  this  treatment  (supplemented  by  the 
administration  of  iron  and  bismuth)  pain  disappears  early,  vomiting 
quickly  subsMes,  and  relapses  are  rare.  The  diet  is  also  easier  to 
carry  out  than  the  old  '  starvation '  plan,  besides  being  more  agreeable 
to  the  patient. 

Acute  and  Chronic  Gastritis. 

The  dietetic  treatment  of  acute  gastritis  must  proceed  on  the  same 
lines  as  that  of  gastric  ulcer.  The  affection,  however,  being  usually 
of  but  short  duration,  rectal  feeding  is  rarely  required,  all  that  is 
necessary  being  to  withhold  all  food  until  vomiting  has  ceased,  thirst 
being  meanwhile  relieved  by  sips  of  hot  water  or  by  sucking  frag- 
ments of  ice.  If  there  is  great  depression,  a  little  champagne  may 
be  given,  preferably  diluted  with  seltzer- water. 

After  the  acute  symptoms  have  subsided,  the  patient  may  gradually 
return  to  ordinary  diet  by  the  same  stages  as  in  gastric  ulcer,  but 
the  steps  of  advance  may  usually  be  separated  by  periods  of  one  or 
two  days  only,  instead  of  by  a  week. 

In  the  treatment  of  chronic  gastritis,  it  is  important  to  avoid  the 
use  of  anything  that  may  irritate  the  gastric  mucous  membrane  or 
excite  a  secretion  of  mucus.  Mustard,  pepper,  spices,  and  con- 
diments of  all  sorts  must  be  forbidden.  Alcohol  also  should  be 
avoided,  especially  in  concentrated  forms,  for  many  of  these  cases 
are  really  brought  on  and  maintained  by  the  drinking  of  neat  spirits. 

1  !\Ied.  Klin.,  No.  14,  1907.  See  also  Langdon  Brown  (Clin.  Journ.,  1908, 
xxxiii.  109). 


ACUTE  AND  CHRONIC  GASTRITIS  527 

Co.Tee  is  apt  to  be  injurious  owing  to  the  oily  substances  which  it 
contains,  but  weak  tea  may  usually  be  permitted. 

Sugar  is  a  very  unsuitable  food  is  these  cases,  more  especially 
cane-sugar  (see  p.  277),  for  it  excites  a  large  secretion  of  mucus. 
Grape  and  milk  sugar  are  m.uch  less  likely  to  do  harm.  All  cooked 
fats,  pastry,  sauces,  and  fat  meats  should  be  excluded  from  the 
dietary  ;  but  butter  is  usually  well  borne  if  taken  in  moderation, 
and  some  patients  can  even  digest  bacon. 

Bread  should  only  be  taken  thoroughly  toasted,  and  potatoes  in 
the  form  of  puree.  Cauliflower  and  spinach  are  the  most  suitable 
of  vegetables.  The  food  should  be  finely  divided,  eaten  slowly,  and 
but  little  taken  at  one  meal.  At  the  same  time  it  is  important  to 
avoid  msre  '  slops.' 

The  following  may  be  regarded  as  a  typical  diet  schedule  for  an 

average  case : 

Breakfast. 

Lightly-cooked  eggs,  white  fish  (boiled),  a  little  crisp  bacon  (not  too  fat),  fowl, 
game ;  dry  toast  with  a  little  butter ;  a  small  cup  of  weak  tea  with  milk 
but  no  sugar. 

Luncheon. 

Lean  mutton,  underdone,  or  underdone  roast  beef,  white  fish,  etc.,  as  at  break- 
fast ;  mashed  potato  and  a  little  spinach  or  cauliilower  ;  dry  toast ;  custard 
pudding  or  unsweetened  jelly  ;  a  glass  of  alkaline  mineral  water,  with 
perhaps  a  little  claret  or  hock. 

Tea. 

A  small  cup  of  tea,  as  at  breakfast ;  a  slice  of  crisp  toast  and  butter,  or  a  plain 
biscuit  or  rusk. 

Duiner. 

A  very  little  clear  soup  free  from  fat ;  white  fish,  without  sauce ;  meat  as  at 
luncheon  or  breakfast,  or  a  little  sweetbread  or  tripe ;  vegetables  as  at 
lunch  ;  custard,  jelly,  or  fruit  stewed  without  sugar,  and  free  from  skins  or 
stones,  or  a  little  plain  milk  pudding ;  a  lith  or  two  of  orange  at  dessert, 
the  juice  only  being  swallowed  and  no  sugar  taken  ;  dry  toast ;  a  glass  or 
two  of  good  claret  or  burgundy  and  some  mineral  water  ;  no  coffee. 

It  may  be  well  to  point  out  that  many  cases  of  alcoholic  gastritis 
stand  midway,  as  regards  the  urgency  of  their  symptoms,  between  the 
acute  and  chronic  forms  of  the  disease,  and  in  such  cases  confinement 
to  bed  on  a  stiict  milk  diet  is  often  the  most  successful  method  of 
treatment. 

Dilatation  of  the  Stomach. 
I.  Obstructive. 

The  kind  of  diet  suitable  for  cases  of  dilated  stomach  must 
obviously  depend  upon  the  degree  of  pyloric  obstruction.     In  all 


528  FOOD  AND  DIETETICS 

cases,  however,  certain  general  principles  must  be  observed :  (i)  It 
is  important  to  avoid  overburdening  the  weakened  organ  with  any 
considerable  mass  of  food  at  one  time.  The  meals,  therefore,  should 
be  small.  (2)  Substances  must  be  excluded  from  the  diet  which  are 
capable  of  supplying  pabulum  to  the  yeasts  and  sarcinse  so  often 
found  in  the  dilated  viscus.  The  food  should,  therefore,  be  unfer- 
mentable.  (3)  Attention  should  be  concentrated  on  rendering  the 
food  easily  passed  on  into  the  intestine,  rather  than  upon  any 
attempt  to  make  it  capable  of  absorption  in  the  stomach  itself.  The 
reason  is  that,  even  under  the  most  favourable  circumstances, 
the  stomach  absorbs  but  little,  and  when  it  is  much  dilated  the 
process  is  probably  arrested  altogether.^  Food  should,  therefore,  be 
given  either  in  a  fluid  or  semi-fluid  form  or  in  a  state  of  very  fine 
division.  (4)  It  must  be  remembered  that  water  is  not  absorbed 
by  the  stomach,  and  if  the  pyloric  stenosis  is  complete  the  tissues 
may  suffer  from  water  starvation.  In  such  cases  it  is  necessary 
to  supply  the  blood  with  fluids  by  another  route  than  the  mouth. 
(5)  In  all  cases  of  dilatation  of  the  stomach,  periodic  lavage  of  the 
organ  is  a  great  aid  to  successful  feeding. 

In  complete  pyloric  obstruction  the  patient  must  be  fed  per  rectum 
(Chapter  XXX.).  An  occasional  saline  enema,  or  the  subcutaneous 
injection  of  salt  solution,  will  be  necessary  to  insure  a  due  supply  of 
fluids. 

If  the  obstruction  be  extreme,  but  not  complete,  peptonized  milk 
should  be  given  in  small  and  frequent  feeds.  The  milk  may  be 
enriched  by  an  unfermentable  sugar,  such  as  lactose,  or  by  the 
addition  of  one  of  the  concentrated  protein  foods  (Plasmon,  etc.). 

In  cases  of  dilatation  with  comparative  freedom  from  pyloric  obstruction 
the  diet  may  follow  very  much  the  lines  already  laid  down  for  chronic 
gastritis,  but  even  greater  care  must  be  exercised  in  the  use  of 
farinaceous  substances  and  fats,  and  the  food  should  be  finely 
divided.  It  is  better  to  avoid  all  effervescing  beverages,  as  they 
tend  unduly  to  inflate  the  stomach.  A  little  hot  water  may  be 
drunk  immediately  after  meals,  and  also  with  advantage  on  going  to 
bed  and  on  first  rising  in  the  morning. 

2.  Non-obstructive  (Atonic  Dilatation). 

In  cases  of  atonic  dilatation  the  diet  should  be  the  same  as  for 
flatulent  dyspepsia  {q-v.).  In  extreme  cases  an  exclusive  protein 
diet  is  sometimes  helpful  (for  details  see  p.  553). 

1  See  Klemperer,  Deut,  Med.  Woch.,  1889,  xv.  170,  and  Verhand.  d.  8ten  Con.  / 
Inn.  Med.,  1889,  271. 


FUNCTIONAL  DYSPEPSIAS  5*9 


Functional  Dyspepsias. 

Under  this  heading  one  may  group  for  convenience  that  large  and 
heterogeneous  class  of  cases  in  which  digestion  is  performed  painfully 
or  with  difficulty,  but  in  which  no  organic  change  in  the  organs  of 
digestion  can  be  discovered.  In  some  of  these  cases  the  chemistry 
of  the  stomach  is  at  fault,  but  in  many  the  basis  of  the  condition 
would  seem  to  consist  rather  in  a  hyperaesthesia  of  the  stomach,  an 
undue  sensitiveness  to  normal  irritants. 

In  treating  them  it  is  essential  to  keep  one  or  two  principles 
clearly  before  one's  mind,  (i)  In  many  of  these  cases  the  patient's 
general  nutrition  requires  to  be  considered  rather  than  his  mere 
gastric  sensations.  If  the  nervous  system  and  blood  can  be  raised 
to  a  proper  level  of  health,  the  dyspeptic  symptoms  often  disappear 
spontaneously.  For  this  reason  great  harm  may  be  done  by  too 
strict  dieting.  The  tendency  in  such  patients  is  to  go  on  cutting  oflF 
one  article  of  food  after  another  until  a  state  of  semi-starvation  is 
induced,  in  which  it  is  impossible  for  any  organ  in  the  body  properly 
to  perform  its  work.  Instead  of  adopting  this  plan,  it  would  be  well 
if  such  patients  could  be  induced  to  follow  the  advice  of  King- 
Chambers,  and  add  to  the  diet  any  article  of  food  that  had  once  been 
found  to  agree,  rather  than  to  cut  out  of  it  anything  that  had  ever 
disagreed.  (2)  Mental  and  physical  rest,  preferably  in  bed,  is  a 
great  and  sometimes  indispensable  aid  to  treatment.  It  acts  both 
by  economizing  vascular  and  nervous  energy  and  by  enabling  nutri- 
tion to  be  efficiently  carried  out  upon  a  minimum  quantity  of  food, 
and  therefore  with  the  least  amount  of  labour  on  the  part  of  the 
digestive  organs.  (3)  In  no  class  of  gastric  disorders  does  the 
question  of  idiosyncrasy  play  a  greater  part  than  in  this.  Due 
regard  must  therefore  always  be  paid  to  the  inclinations  of  individual 
patients  in  arranging  the  diet-sheet. 

In  all  cases  of  this  class  the  same  elementary  dietetic  rules  must 
be  observed  as  in  other  forms  of  digestive  trouble.  The  food  must 
be  in  a  suitable  physical  form,  all  notoriously  indigestible  articles 
being  avoided ;  the  meals  should  be  properly  arranged,  and  chewing 
carefully  performed.  To  these  simple  directions  one  need  only  add 
that  good  cooking  and  attractive  presentation  of  the  meals  are  here 
of  the  first  importance. 

In  all  cases  the  most  easily  digested  foods  should  be  selected, 
these  being : 

34 


530  FOOD  AND  DIETETICS 

'  (a)  Meats:    Mutton,   venison,   sweetbreads,   chicken,     tripe,    rabbit,    grouse, 

partridge,  pheasant. 
(6)  Fish  :  Whiting,  sole,  turbot. 
(c)  Farinaceous  foods :  Stale  white  bread,  rusks,  plain  biscuits,  rice,  tapioca, 

sago,  arrowroot. 
{d)  Vegetables :  Asparagus,  sea-kale,  spinach,  cauliflower,  French  beans. 
{e)  Fruits  :  Baked  apples,  or  the  juice  of  oranges  or  grapes. 
'  Made  dishes,'  twice  cooked  meats,  sauces,  pastry,  pickles,  cheese,  sweets  and 

preserves  should  be  avoided  altogether.     Meat  should  be  underdone  ; 

fish  should  be  boiled  or  steamed. 

The  special  rules  of  diet  will  depend  upon  the  particular  form  of 
dyspepsia  with  which  one  has  to  deal.  For  practical  purposes  one 
may  distinguish  the  following  varieties : 

1.  Defective  secretion  (hypochlorhydria  and  achylia). 

2.  Excessive  secretion  (hyperchlorhydria). 

3.  Defective  motility  ('  atonic  '  dyspepsia). 

4.  Excessive  sensibility  (gastralgia). 

The  principles  to  be  observed  in  prescribing  rules  of  diet  in  each 
of  these  forms  may  now  be  briefly  discussed. 

1.  Defective  Secretion. — In  cases  of  this  sort  the  mechanical  form  of 
the  food  is  of  much  greater  importance  than  its  chemical  conaposi- 
tion.  So  long  as  the  motor  power  of  the  stomach  is  unimpaired  the 
defect  of  secretion  is  not  of  much  account,  for  digestion  will  be  fully 
performed  in  the  intestine.  The  food  should  therefore  be  finely 
divided  (pounded,  minced,  or  sieved),  in  order  to  facilitate  its 
passage  through  the  stomach,  and  thorough  mastication  insisted 
upon.  If  this  principle  be  observed  an  ordinary  mixed  diet  may  be 
safely  prescribed.  Even  when  secretion  is  completely  arrested 
(achylia)  this  may  be  done  without  risk,  unless  there  is  evidence 
of  protein  decomposition  in  the  intestine,  as  shown  by  offensive 
eructations  or  a  tendency  to  diarrhoea.  In  that  case  meat  should  be 
strictly  limited  in  amount,  or  even  abolished  from  the  diet  altogether, 
its  place  being  taken  by  peptonized  milk  and  the  casein  preparations 
(e.g.,  Plasmon). 

2.  Excessive  Secretion. — Much  discussion  has  taken  place  as  to 
whether  the  diet,  in  cases  of  hypersecretion,  should  be  mainly 
animal  or  vegetable  in  constitution.^  On  the  one  hand,  there  is  no 
doubt  that  an  animal  diet  '  fixes  '  the  excess  of  hydrochloric  acid 
most  efficiently,  whilst  on  the  other  there  is  abundant  evidisnce 
to  show  that  in  the  long-run  a  mainly  vegetable  diet  leads  to  a 
permanent  diminution  of  acid  formation.  An  animal  diet  is  there- 
fore the  best  palliative,  whilst  a  vegetable  diet  is  more  strictly 
curative  in  eflfect.     The  writer's  own  experience  is  that  in  practice 

*  See  Schloss,  '  Vegetabilische  oder  Fleischnahrung  bei  Hyperaciditat '  (Arch. 
/.  Vtrdauvngs  Krankh.,  1907,  xiii.  233). 


FUNCTIONAL  DYSPEPSIAS  531 

a  predominatingly  animal  diet  gives  the  best  results,  whilst  other 
means  may  be  relied  upon  for  actually  lessening  secretion  {e.g.,  the 
free  use  of  fats,  administration  of  bismuth,  etc.). 

On  the  other  hand,  it  is  reasonable  to  exclude  all  direct  stimulants 
of  secretion.  Under  this  heading  come  such  substances  as  common 
salt,  extractives  of  meat,  the  various  condiments,  and  alcoholic 
beverages. 

As  there  is  both  experimental  and  clinical  evidence^  to  show  that 
fats  have  a  restraining  influence  on  gastric  secretion  they  should  be 
partaken  of  freely.  As  much  as  an  ounce  of  almond  oil  may  be 
given  before  meals  with  advantage,  especially  in  cases  complicated 
by  ulceration. 

Foods  rich  in  carbohydrates,  on  the  other  hand,  must  be  eaten 
sparingly,  as  free  acid  appears  in  the  stomach  very  early  after  their 
use,  and  the  conversion  of  their  starch  by  the  saliva  is  interfered 
with.  For  this  reason  the  addition  of  malt  to  farinaceous  foods  is 
often  of  great  service  in  cases  of  hyperacidity.  Cane-sugar  being  a 
potent  excitant  of  secretion  should  be  avoided  altogether.  It  is 
particularly  harmful  in  cases  of  acid  gastritis.  It  stands  to  reason 
that  where  *  acidity '  of  the  stomach  is  complained  of,  all  sour 
articles  should  be  banished  from  the  diet.  Vinegar  and  some  wines 
are  examples  in  point. 

The  application  of  the  above  principles  may  be  expressed  in  the 
following  rules : 

Directions  for  Diet  in  Hyperchlorhydria. 

1.  The  diet  should  consist  mainly  of  animal  constituents  (milk,  eggs,  fish, 

and  meat). 

2.  Salt,  pepper,  mustard,  meat  extracts,  gravies,  meat  soups,  spices,  pickles 

and  condiments  should  be  altogether  avoided. 

3.  Bread  and  potatoes  should  be  taken  very  sparingly,  but  bacon  and  butter 

may  be  eaten  freely. 

4.  Sugar  and  all  sweet  or  sour  things  should  not  be  eaten. 

5.  Alcoholic  beverages  should  be  avoided.     The  best  drink  at  meals  is  an 

alkaline  water  such  as  ApoUinaris. 

3.  Defective  Motility  (Atonic  or  Flatulent  Dyspepsia). — In  this  form 
of  dyspepsia  the  mechanical  form  of  the  food,  as  in  cases  of  defective 
secretion,  is  of  chief  importance.  It  is  essential  to  avoid  burdening 
the  stomach  with  large  quantities  of  material,  especially  such  as  is 
of  a  bulky  sort  {e.g.,  green  vegetables).  The  simultaneous  presence 
in  the  stomach  of  solids  and  liquids  is  specially  injurious,  for  in  such 
circumstances  the  fluid  part  of  the  meal  is  retained  for  a  long  time  in 
the  organ,  and  tends  to  dilate  it  by  its  mere  weight.     The  meals 

^  See  Backman  {Zeit.  f.  Klin.  Med.,  igoo.  xl.  224),  and  Craven  Moore  and 
Ferguson  (Proc.  Roy.  Soc.  of  Med  ,  Laryng.  Sect.,  1909,  in.  25). 


538  FOOD  AND  DIETETICS 

should  therefore  be  dry,  and  care  should  be  taken  not  to  drink  for  at 
least  two  hours  after  solid  food  has  been  taken. 

If  flatulence  be  much  complained  of — as  it  often  is — green  vege- 
tables and  the  pulses  should  be  avoided  altogether,  on  account  of 
their  '  windy  *  tendency,  and  the  starchy  foods  should  be  strictly 
limited.  The  necessity  for  reducing  the  starches  in  flatulence  is  a 
principle  derived  from  experience  for  which  it  is  difficult  to  find  a 
satisfactory  reason.  It  certainly  does  not  reside  in  the  '  fermentable  * 
character  of  starchy  food,  for  the  flatulence  of  atonic  dyspepsia  is 
almost  certainly  not  due  to  fermentation,  but  there  is  no  doubt  about 
the  practical  harmfulness  of  the  carbohydrates,  explain  it  how  one 
may. 

Restriction  of  fluids  is  also  of  special  importance  in  cases  of 
flatulence,  tea,  especially,  being  peculiarly  noxious  to  these  patients. 
On  the  other  hand,  it  is  in  atonic  dyspepsia  that  the  moderate  use  of 
alcoholic  beverages  at  meals,  preferably  in  the  form  of  a  little  sound 
wine,  often  gives  the  happiest  results,  for  alcohol  is  a  stimulant  both 
to  the  secretory  and  motor  functions  of  the  debilitated  stomach. 

The  above  general  principles  may  be  summed  up  in  the  following 
directions : 

Directions  for  Diet  in  Atonic  and  Flatulent  Dyspepsia 

1.  The  following  articles  should  be  avoided  : 

Green  vegetables  (except  spinach  and  cauliflower  tops)  ;  turnip  and 
carrots ;  peas,  beans,  and  lentils  ;  fruits  (except  the  pulp  of  baked 
apples  or  stewed  prunes) ;  sugar  and  jam  ;  soups. 

2.  Potatoes  should  be  taken  very  sparingly. 

3.  Crisp  toast,  rusks  or  pulled  bread  should  be  taken  in  place  of  ordinary 

bread. 

^.  As  little  fluid  as  possible  should  be  taken  at  meals.     A  little  hot  water  may  be 
sipped  between  meals  if  flatulence  is  troublesome. 

5.  Tea  should  be  avoided  entirely,  and  coffee  only  taken  with  plenty  of  milk. 

The  above  rules  are  applicable  in  all  cases  of  atonic  dyspepia  of 
moderate  degree.  In  severe  cases,  however,  in  which  there  is  pro- 
nounced dilatation  of  the  stomach  (non-obstructive),  an  'exclusive 
protein  diet '  is  sometimes  indicated.  Such  a  diet  is  described  in 
detail  elsewhere  (p.  553).  Far  more  commonly  one  has  to  deal  with 
cases  in  which  the  gastric  atony  is  merely  part  of  a  general  condition 
of  neurasthenia,  and  it  is  then  often  complicated  (especially  in 
women)  by  visceral  ptosis.  In  such  cases  one  must  ignore  the 
gastric  symptoms  and  improve  the  general  state  of  nutrition  at  all 
costs,  for  it  is  only  when  this  has  been  accomplished  that  normal 
digestive  power  returns.     The  best  way  of  doing  this  is  by  a  course 


DIARRHCEA  533 

of  over-feeding  combined  with  rest  in  bed  and  massage  (Weir  Mitchell 
treatment  or  rest-cure).     For  details  of  such  treatment  see  p.  511. 

4.  Hypev-sensihility  of  the  Stomach  (Gastralgia). — The  diet  here  must 
be  of  a  '  bland  '  character,  such  as  is  suitable  in  the  early  stages  of 
gastric  ulcer  (see  p.  524).  Rest  in  bed  greatly  facilitates  the  use  of 
such  a  plan.  So  soon  as  pain  disappears  a  liberal  mixed  diet  should 
be  adopted  in  order  to  improve  the  state  of  the  blood  and  the  general 
nutrition  of  the  patient.  Red  meat  should  be  given  as  early  as 
possible,  particularly  as  patients  who  suffer  from  gastralgia  are  often 
anaemic  and  debilitated  from  the  habitual  use  of  a  poor  diet  defective 
in  protein.  If  these  principles  be  observed  no  special  rules  will  be 
required. 

Diseases  of  the  Intestines. 

In  acute  diarrhoea  the  chief  point  to  be  aimed  at  in  feeding  is  to 
select  a  diet  which  shall  be  unirritating,  and  shall  leave  as  small  an 
unabsorbed  residue  as  possible.  If  the  diarrhoea  be  very  severe,  it 
may  be  necessary  to  withhold  all  food  for  a  day  or  two,  nothing 
being  given  by  the  mouth  but  a  little  barley-water  to  quench  thirst. 
When  the  symptoms  have  somewhat  abated,  and  in  milder  cases 
from  the  outset,  one  can  allow  weak  decoctions  of  cereal  preparations, 
such  as  arrowroot,  rice,  cornflour,  sago,  or  one  of  the  patent  cereal 
foods.     These  should  be  given  at  the  body  temperature. 

By-and-by  one  can  begin  to  give  milk,  but  tentatively  and  always 
safeguarded  with  a  little  lime-water.  Raw-meat  juice,  alum-whey, 
egg-white  solution,  and  the  pulp  of  underdone  beef  are  also  useful ; 
but  all  solutions  containing  the  extractives  of  meat  are  best  avoided. 

If  the  patient  be  very  thirsty,  he  may  be  allowed  sips  of  cold  tea 
or  diluted  red  wine,  or  water  flavoured  with  a  little  lemon-juice. 

In  cases  of  chronic  diarrhoea,  all  bulky  foods  and  those  which  leave 
a  large  residue  or  which  contain  laxative  principles  should  be  avoided. 
Amongst  such  are  green  vegetables,  fruits,  and  all  sour  things.  Hot 
liquids  should  Rot  be  taken.  Alcoholic  beverages  are  best  avoided. 
Milk  must  be  given  with  caution  :  in  some  cases  it  increases  the 
diarrhoea,  in  others  not.  It  is  safest  when  freely  diluted  with  lime- 
water. 

The  further  details  of  the  diet  must  depend  upon  the  cause  of  the 
diarrhoea.  If,  for  example,  it  be  due  to  defective  secretion  of  gastric 
juice  ('  gastrogenic '  diarrhoea),  the  diet  must  be  arranged  as  in  cases 
of  achylia  (p.  530).  If  it  be  due  to  fermentation  in  the  bowel,  the  diet 
must  be  arranged  according  to  the  nature  of  the  fermentation.  If  it 
be  the  carbohydrates  which  are  at  fault,  as  shown  by  the  passage  of 


534  FOOD  AND  DIETETICS 

acid  stools,  the  starches  must  be  reduced  to  a  minimum.  In  such  a 
case  a  diet  of  milk,  casein  preparations,  and  underdone  meat  may 
suit  best.  If,  on  the  other  hand,  there  is  decomposition  of  proteins 
with  alkaline  offensive  stools,  meat  must  be  withheld  entirely,  and 
the  diet  consist  of  milk  and  carbohydrates.  If  the  stools  are  white, 
greasy,  and  show  fat  droplets,  fat  should  be  withdrawn  from  the 
diet,  and  skim  milk,  casein  preparations,  carbohydrates,  and  under- 
done meat  made  the  basis  of  the  regimen. 

In  cases  of  nervous  diarrhoea  there  are  no  special  rules  of  diet,  but 
the  experience  of  the  patient  should  be  made  the  guide  as  to  what  to 
eat,  drink,  and  avoid. 

In  the  treatment  of  the  special  form  of  diarrhoea  known  as  sprue, 
a  strict  milk  diet  is  generally  recommended  by  the  best  authorities. 
At  first  3  pints  of  milk  are  allowed  daily,  in  hourly  or  two-hourly 
feeds.  In  a  few  days  the  quantity  may  be  increased  to  5  pints  a 
day,  and  after  ten  days  to  as  much  as  6  or  7  pints  in  the  twenty-four 
hours.  The  strict  milk  diet  should  be  continued  for  six  weeks  after 
the  stools  have  become  solid,  after  which  the  diet  may  be  gradually 
advanced,  much  in  the  same  way  as  in  gastric  ulcer.  If  after  a 
period  of  rigid  milk  diet  the  patient  is  unable  to  return  to  ordinary 
food,  a  course  of  •  Salisbury  treatment  *  (p.  553)  may  be  useful. 
Strawberries  have  been  asserted  to  have  an  almost  specific  influence 
in  controlling  the  diarrhcea  of  sprue,  and  as  much  as  i^  pounds  of 
them  have  been  given  daily  with  apparent  success.^ 

Authorities  are  divided  as  to  the  best  form  of  diet  in  cases  of 
dysentery.  In  acute  cases  mild  starvation  is  probably  the  best  plan, 
beginning  with  thin  broths  and  decoctions  of  cereals  as  in  acute 
diarrhoea,  and  passing  on  to  milk,  either  plain,  peptonized,  or  suitably 
diluted,  so  soon  as  the  tongue  is  clean.  In  chronic  cases  a  more 
generous  diet  is  advisable,  but  all  coarse  and  irritating  foods  and  such 
as  leave  a  large  residue  in  the  bowel  should  be  avoided.  Bilberries 
are  strongly  recommended  by  Demstein^  in  chronic  dysentery. 

In  acute  and  ulcerative  colitis  the  diet  should  be  the  same  as  for 
acute  and  chronic  dysentery  respectively.  In  muco-mem'braiious 
colitis  two  distinct  plans  are  advocated:  (i)  Most  French  writers, 
influenced  by  their  experience  at  Plombiferes,  recommend  a  diet 
which  leaves  as  little  residue  in  the  bowel  as  possible,  the  diet 
consisting  of  lightly  cooked  eggs,  pounded  meat  or  fish,  sieved 
potatoes,  toast,  rusks  or  biscuits,  rice,  the  Italian  pastes,  milk,  if  it 
can  be  digested,  and  the  pulp  of  ripe  fruits.     (2)  Von  Noorden,  on 

»  For  an  illustrative  case,  see  a  paper  by  Ycung,  Lancet,  March  28,  1903. 
*  Brit.  Med.  Journ.,  February  7,  1902. 


MUCOUS  COLITIS  533 

the  other  hand,  recognizing  that  constipation  is  an  essential  part  of 
the  disease,  urges  that  the  diet  should  be  bulky,  and  contain  much 
cellulose  and  other  articles  suitable  for  cases  in  which  there  is 
sluggish  action  of  the  bowels. 

The  irritating  effects  of  such  a  diet  are  obviated  by  adding  to  it 
large  quantities  of  fat  in  various  forms.  Ransome  ^  gives  the  follow- 
ing as  a  typical  dietary  which  possesses  the  essentials  of  the  treat- 
ment, but  in  which  modifications,  especially  in  quantities,  must  be 
made  to  suit  individual  cases  : 

7  a.m. — \  pint  milk-cream  mixture. 

8  a.m. — \  pint  Kissingen  water. 

9  a.m. — \  pint  cocoa  with  cream  (2  oz.),  bread  (2  oz.),  butter,  marmalade. 
10.30  a.m. — Massage. 

11.30  a. »/. — 12  oz.  special  soup;  3  oz.  bread;  i  oz.  butter;  potatoes,  green 
vegetables,  baked  apple,  stewed  pears,  or  boiled  gooseberries ;  cream. 
Rest  for  two  hours  with  hot  bottle  on  abdomen. 

^p.m. — ^  pint  milk-cream  mixture. 

•J p.m. — Dinner  like  lunch,  but  with  3  oz.  bread  and  2  oz.  butter, 

g. 30 />.»!. — \  pint  milk-cream  mixture. 

A  description  of  certain  items  in  this  dietary  may  be  found  useful. 

Milk-Cream  Mixture. — This  consists  of  equal  parts  of  milk  and  cream,  and 
one  teaspoonful  of  sugar  of  milk.  The  cream  should  contain  30  per  cent, 
of  butter-fat,  and  nearly  a  pint  should  be  taken  in  the  twenty-four  hours. 

Kissingen  Water. — This  is  used  as  a  stomachic,  not  as  an  aperient. 

Bread. — This  must  be  of  the  coarsest  flour  obtainable.  The  larger  proportion 
of  husk  it  contains  the  better.  The  usual  brown  bread  sold  as  whole- 
meal bread  is  not  sufficiently  coarse. 

Butter. — The  average  total  quantity  should  be  \  lb.  a  day  ;  5  or  6  oz.  of  this 
is  taken  with  bread,  the  remainder  being  used  with  the  vegetables. 

Special  Vegetable  Soup. — This  should  be  prepared  carefully  according  to  the 
following  directions.  Preparation  of  vegetable  pulp  :  Place  a  breakfast- 
cupful  of  lentils  or  dry  peas  in  a  pan  in  sufficient  cold  water  to  cover 
them,  and  allow  them  to  soak  all  night.  In  the  morning  add  a  slice  of 
fat  bacon  about  6  ins.  by  2  ins  and  J  in.  thick,  and  boil  for  one  hour. 
Put  one  teaspoonful  of  butter  and  one  of  flour  into  a  small  pan  on  the 
fire,  add  a  teacupful  of  milk  gradually,  stirring  all  the  time  until  well 
mixed.  Then  add  a  teaspoonful  of  cream  and  mix  with  the  pulp.  To 
vary  the  flavour,  a  sufficient  quantity  of  green  peas,  spinach,  asparagus, 
or  other  green  vegetable  should  be  placed  in  cold  water  and  boiled  for 
half  an  hour,  rubbed  through  a  sieve,  and  added  to  the  soup.  The  soup 
should  contain  all  the  husks  of  the  peas  or  lentils,  and  should  be  more  of 
the  consistency  of  porridge  than  of  soup. 

Meat. — This  may  be  of  any  kind,  but  is  more  easily  digested  if  prepared  as 
follows  :  It  is  cut  up  finely  with  a  sharp  knife,  and  thoroughly  pounded 
in  a  mortar  while  raw.  It  is  then  mixed  with  sufficient  beaten-up  white 
of  egg  and  milk  to  make  a  thick  cream,  placed  in  a  china  cup,  and 
boiled  in  a  pan  of  water  for  three  to  five  minutes,  being  well  stirred 
during  the  process. 

Vegetables. — These  should  be  of  the  coarse  green  varieties— cabbage,  spinach, 
Brussels  sprouts — well  boiled  and  mashed  with  butter. 

*  See  Abst.  in  Ther.  Gaz.,  November  15,  1908. 


536  FOOD  AND  DIETETICS 

As  the  diet  is  rather  trying  at  first,  it  is  best  to  begin  treatment 
with  the  patient  in  bed,  preferably  in  a  hospital  or  nursing  home. 
When  a  natural  daily  evacuation  of  the  bowels  has  been  established, 
the  patient  is  allowed  to  get  up,  and  may  gradually  return  to  ordinary 
life  and  to  a  more  usual  diet,  but  plenty  of  coarse  bread,  vegetables 
and  fat  should  remain  a  permanent  feature  of  the  regimen. 

In  the  acute  diarrlicea  of  infancy  all  milk  must  be  stopped  for  at 
least  twenty-four  hours,  and  nothing  given  but  egg-white  solution 
(the  white  of  one  egg  to  \  pint  of  water,  flavoured  with  a  little  milk- 
sugar).  Raw-meat  juice  and  alum-whey  are  also  very  useful  in  such 
a  case,  and  at  a  later  stage  the  white  of  egg  mixture  may  be  made 
with  whey  instead  of  with  water.  When  milk  is  begun  again,  it 
should  be  given  peptonized  at  first,  and  well  diluted  with  lime-water. 
The  administration  of  salt  solution,  either  per  rectum  or  subcu- 
taneously,  will  often  tide  over  the  crisis  in  an  acute  case. 

In  the  treatment  of  constipation  much  can  be  accomplished  by 
suitable  diet.  Food  can  increase  peristalsis  either  by  (i)  mechanical 
or  (2)  chemical  action. 

Foods  which  leave  a  large  amount  of  residue  or  '  ballast '  in  the 
intestine  act  in  the  former  way.  Generally  speaking,  all  foods  rich 
in  cellulose  belong  to  this  class,  e.g.,  oatmeal,  green  vegetables, 
wholemeal  bread,  and  some  fruits.  All  of  these  should  therefore 
find  a  place  in  the  diet.  Water  also  acts  in  a  large  measure 
mechanically  by  increasing  the  fluidity  of  the  intestinal  secretion,  but 
in  part  also  its  action  may  be  reflex.  It  is  best  given  cold  the  first 
thing  in  the  morning.  In  districts  in  which  the  water  contains  much 
lime  a  pure  artificial  aerated  water  should  be  taken  instead  {e.g., 
Salutaris).  Fats  and  oils,  too,  act  as  mechanical  lubricants,  and 
sufferers  from  constipation  should  partake  of  all  of  them  freely, 
especially  if  the  motions  are  small  and  dry.  Honey,  treacle,  and 
marmalade  have  also  a  slightly  aperient  action. 

The  chemical  action  of  foods  is  usually  brought  about  by  the 
organic  acid  which  they  contain.  It  is  probable,  indeed,  that 
foods  rich  in  cellulose  owe  their  laxative  properties  largely  to  the 
fact  that  they  are  very  apt  to  undergo  fermentation  in  the  intestine, 
with  the  production  of  lactic,  acetic,  and  other  acids. 

Fruits  are,  of  course,  the  foods  richest  in  organic  acids,  and  should 
always  be  freely  used  in  such  cases.  They  may  be  taken  either  fresh 
or  stewed,  figs  and  prunes  being  perhaps  the  best  forms  to  select. 

Of  beverages,  cider  has  a  decidedly  laxative  action,  though  it  is 
apt  to  produce  colic  in  many  persons,  and  malt  liquors  sometimes 
act  similarly.     On  the  other  hand,  red  wines  are  usually  astringent, 


DISEASES  OF  THE  LIVER  537 

and  so  often  is  sherry.  Milk  is  also  a  very  constipating  fluid,  and  so 
are  tea  and  coffee  to  some  persons.  At  least  3  pints  of  liquid  should 
be  taken  in  the  course  of  the  day. 

These  principles  are  expressed  in  the  following  rules  for  patients : 

Directions  for  Diei  in  Chronic  Constipation. 

I.  The  following  foods  should  be  partaken  of  freely  : 

Porridge  made  from  medium  oatmeal  ;  whole-meal  bread  ;  gingerbread 
and  '  ginger  snaps ';  green  vegetables  ;  fruits  (fresh  or  stewed — 
especially  stewed  prunes  or  figs  and  baked  apples)  ;  marmalade, 
honey  and  treacle. 

Fats — e.g.,  bacon  fat,  butter,  salad  oil. 

«>.  The  following  should  be  avoided  : 

Milk  ;  eggs  ;  strong  tea  and  coffee  ;  red  wines. 

3.  A  glass  of  cold  water  should  be  taken  on  rising,  and  a  few  French  plums 
may  be  eaten  before  going  to  bed. 

Diseases  of  the  Liver. 

In  the  dietetic  treatment  of  hepatic  cirrhosis  the  first  indication  is 
to  counteract  the  tendency  to  gastric  catarrh,  which  almost  always  co- 
exists along  with  the  derangement  of  the  liver  even  if  it  be  not  causally 
related  to  the  latter.  The  most  suitable  diet,  therefore,  will  be  one 
which  follows  very  much  upon  the  lines  of  that  already  laid  down 
for  cases  of  chronic  gastritis.  Seeing  that  the  liver  cells  also  serve 
as  storehouses  for  fat  and  glycogen,  it  will  be  well  also  that  all  rich, 
fatty  foods  should  be  avoided,  and  that  carbohydrates,  particularly 
sugar,  should  be  eaten  very  sparingly.  Alcoholic  beverages  should 
be  strictly  forbidden,  except,  perhaps,  in  the  very  latest  stages  of  the 
disease,  and  all  spices  and  condiments  must  also  be  looked  upon  as 
harmful. 

There  are  but  few  indications  to  be  met  in  the  dietetic  treatment 
of  cases  of  gall-stones.  Seeing  that  the  taking  of  food  into  the 
stomach  stimulates  the  expulsion  of  bile,  it  will  be  well  to  see  that 
the  meals  are  rather  frequent — at  least  five  being  taken  in  the 
course  of  the  day.  There  is  no  scientific  justification  for  qualitative 
alterations  of  the  diet,  however,  for  it  does  not  seem  that  the  inges- 
tion of  food  containing  much  cholesterol  or  salts  of  lime  appreciably 
influences  the  composition  of  the  bile,^  even  though  it  might  seem  on 
a  priori  grounds  that  such  articles  would  be  likely  to  promote  the 
formation  of  calculi.  On  the  other  hand,  most  clinical  observers  are 
agreed  that  the  drinking  of  large  quantities  of  water  is  advisable, 

^  See  Aldor,  Zeit.  /.  Physik.  und  Dial.  Therapie,  1903,  vii.  201.  Notwith- 
standing this,  it  is  advisable  to  limit  the  consumption  of  eggs  and  milk  by 
patients  who  suffer  from  gall-stones,  as  these  are  both  foods  rich  in  cholesterol. 


538  FOOD  AND  DIETETICS 

even  although  there  is  no  actual  experimental  evidence  to  show  that 
the  fluidity  of  the  bile  is  increased  thereby. 

In  cases  in  which  jaundice  is  a  prominent  symptom  the  consump- 
tion of  fats  should  be  greatly  restricted,  for  if  bile  is  not  entering  the 
intestine  freely,  the  absorption  of  fat  is  interfered  with,  the  result 
being  that  it  not  only  retards  the  digestion  of  the  other  constituents 
of  the  food,  but  itself  undergoes  bacterial  decomposition,  with  the 
production  of  irritating  fatty  acids.  The  diet  should  be  of  a  simple 
character,  and  may,  with  advantage,  contain  plenty  of  fresh  vegetables 
and  fruit.  Milk,  on  the  other  hand,  should  be  avoided  or  only  given 
skimmed,  or  whey  may  be  substituted  for  it. 

In  cases  of  •  biliousness ' — si  condition  which  is  perhaps  due  to 
functional  disorder  of  the  liver— milk,  eggs,  and  all  rich  and  greasy 
foods  should  be  avoided,  and  meat  taken  sparingly.  The  diet 
may  consist  of  the  white  meats,  and  fish,  toast,  vegetables,  and 
fresh  and  stewed  fruits.  Alcohol  should  be  forbidden  entirely. 
In  chronic  cases  the  diet  should  be  the  same  as  for  chronic 
gastritis  {q.v.). 

4.  Disorders  of  the  Circulation. 
The  consideration  of  the  dietetic  treatment  of  cardiac  disease 
follows  naturally  upon  that  of  digestive  disorders,  for  no  two  organs 
are  in  closer  sympathy  than  the  heart  and  the  stomach,  and  by 
lightening  the  w  ork  of  the  latter  one  indirectly  aids  the  former.  When 
the  heart's  action  is  impaired,  the  diet  should  be  easily  digested  and 
non-flatulent,  and  the  food  should  be  given  in  small  quantities  at  a 
time  at  not  too  short  intervals,  and  should  be  rather  dry.  The 
limitation  of  fats  is  also  quite  as  important  as  in  cases  of  dyspepsia, 
for  there  is  reason  to  believe  that  fats  are  badly  absorbed  in  cases  of 
severe  cardiac  disease.  Carbohydrates  must  also  be  used  very 
sparingly,  owing  to  their  tendency  to  produce  flatulence.  Hence  it 
is  that  the  diet  of  cardiac  disease  must  be  pre-eminently  nitrogenous 
in  its  nature.  The  object  of  all  this  is  to  prevent  overdistension  of 
the  stomach,  which  is  apt  to  be  followed  by  embarrassment  of  the 
heart.  In  the  main,  therefore,  the  same  principles  must  be  attended 
to  as  in  the  dietetic  treatment  of  dyspepsia.^ 

^  See  Grassmann,  Zeit.  f.  Klin.  Med.,i88g,  xv.  183. 

2  G.  W.  Balfour  ('The  Senile  Heart,'  p.  240)  lays  down  the  following  dietetic 
rules  for  patients  with  weak  hearts : 

i.  There  must  never  be  less  than  five  hours  between  each  meal, 
ii.  No  solid  food  is  ever  to  be  taken  between  meals. 
iii.  All  those  with  weak  hearts  should  have  their  principal  meal  in  the  middle 

of  the  day. 
iv.  All  those  with  weak  hearts  should  have  their  meals  as  dry  as  possible. 


DIET  IN  CARDIAC  DISEASE  539 

The  value  of  a  dry  diet  in  cardiac  disease  has  been  specially  in- 
sisted upon  by  several  writers.^  Its  beneficial  action  is  probably 
exercised  in  several  ways :  (i)  In  cardiac  disease  fluids  are  absorbed 
very  slowly,  and  are  therefore  apt  to  interfere  with  digestion  and 
produce  flatulence ;  (2)  if  fluids  are  withheld,  the  blood  tends  to 
become  more  concentrated,  and  water  then  passes  into  it  out  of  the 
tissues,  and  thus  the  absorption  of  dropsical  effusions  is  aided  ;^ 
(3)  the  sudden  entrance  of  any  considerable  quantity  of  fluid  into  the 
circulation  throws  a  mechanical  strain  upon  the  heart  by  increasing 
the  amount  of  blood  which  has  to  be  propelled  round  the  circulation. 
Thus  limitation  of  fluids  lessens  the  work  of  the  heart  (see  also 
p.  301). 

In  cardiac  dropsy,  therefore,  and  especially  if  complicated  by 
obesity,  the  quantity  of  fluid  allowed  should  be  limited  to  about 
20  ounces  per  day,  and  not  more  than  5  ounces  should  ever  be  taken 
at  one  time.  If  much  thirst  is  experienced,  it  may  be  relieved  by 
sucking  a  few  acid  drops. 

The    following    is   a   scheme   of    diet    for   patients    with    weak 

hearts : 

Breakfast,  8.30. 

About  ij  oz.  of  dry  toast  with  butter,  a  lightly-cooked  egg  or  a  little  white 
fish ;  3  to  5  oz.  of  tea  or  coffee  with  cream  and  sugar. 

Lunch  or  Dinner,  1.30  to  2  o'clock  {the  principal  meal  0/  the  day). 

Two  courses  only,  fish  and  meat,  fish  and  pudding,  or  meat  and  pudding. 
Soups,  pastry,  pickles  and  cheese  absolutely  forbidden.  The  most  digestible  forms 
of  meat  or  fish  to  be  selected  ;  one  potato  or  a  little  spinach.  Any  form 
of  simple  milk  pudding  may  be  taken  or  a  little  fruit.  During  the  meal 
4  to  5  oz.  of  hot  water  may  be  sipped  if  desired. 

Tea,  5  <o  6  o'clock. 
3  or  4  oz.  of  weak  tea  with  cream  and  sugar,  but  no  solid  food. 

Supper,  about  7  o'clock. 

Must  always  be  a  light  meal.  May  consist  of  white  fish  and  a  potato,  or  toast 
with  butter,  or  some  milk  pudding  or  bread  and  milk.  4  or  5  oz.  of  hot 
water  may  be  taken  at  bedtime. 

In  the  treatment  of  the  flatulence,  which  is  often  such  a  distressing 
accompaniment  of  heart  failure,  especially  when  associated  with 
emphysema,  the  meals  should  also  be  small  and  dry.  Biscuits  or 
rusks  should  be  substituted  for  bread,  and  lemon-juice  for  vegetables. 

^  See  Oertel,  Leyden's  '  Handbuch  der  Ernahrungstherapie,"  Bd.  ii.,  p.  55 
et  seq.;  also  Cheadle,  Lancet,  1877,  ii.  758,  794,  838,  877;  Dickinson,  Clifford 
Allbutt's  'System  of  Medicine,'  v.  690;  and  Balfour,  'The  Senile  Heart," 
chap.  X. 

2  Cheadle  particularly  insists  upon  the  importance  of  limiting  the  intake  of 
fluids  in  cases  of  ascites,  even  when  due  to  cirrhosis  {Lancet,  1900,  i.  903). 


540 


FOOD  AND  DIETETICS 


Meat  should  be  only  once  cooked,  and  rather  underdone,  and  all 
soups,  sauces  and  fruits  should  be  avoided. 

While  some  such  diet  as  the  above  may  be  adopted  with  advantage 
by  patients  with  weakness  of  the  muscular  substance  of  the  heart,  it 
must  be  remembered  that  in  cases  of  acute  cardiac  disease,  and  often 
enough  where  there  is  severe  impairment  of  compensation,  and  con- 
sequently great  interference  with  digestion,  it  may  be  necessary  to 
have  recourse  to  fluid  diet,  milk  or  peptonized  milk  being  given  in 
small  quantities  at  short  intervals  of  time. 

The  dietetic  treatment  of  aneurysm  requires  a  word  of  mention. 
Our  object  here  must  be  to  diminish  the  force  of  the  heart  and  to 
increase  the  coagulability  of  the  blood. 

Valsalva  claimed  that  he  was  able  to  do  this  by  a  process  of 
starvation.  He  used  only  bread  and  water  or  pudding  and  water, 
giving  as  little  as  half  a  pound  of  pudding  night  and  morning.  His 
patients  often  became  so  weak  that  they  were  unable  to  sit  up  in  bed. 
Some  good  observers  have  spoken  highly  of  this  method,''  but  for  the 
most  part  it  is  now  but  rarely  adopted. 

Tuffnell's  diet  for  aneurysm  is  somewhat  less  severe,  and  can  be 
followed  out  for  longer  periods.     He  allowed  4  ounces  of  bread-and- 
butter,  2  or  3  ounces  of  meat,  4  ounces  of  milk,  and  3  or  4  ounces  of" 
claret,  daily.     Here  again  the  chief  characteristic  of  the  diet  is  its 
extreme  dryness. 

In  cases  of  high  arterial  tension  secondary  to  chronic  nephritis, : 
the  diet  must  be  the  same  as  in  that  disease  (p.  543).  In  primary: 
cases  of  high  tension,  diet  is  often  of  little  use  in  treatment,  but  itj 
may  be  necessary  in  gross  feeders  to  reduce  the  total  intake  of  fooc 
and  especially  of  meat  and  things  derived  from  it — e.g.,  soups.  Salt! 
should  also  be  forbidden.  Alcohol  is  probably  best  avoided,  and  inj 
the  main  the  diet  may  follow  much  the  same  lines  as  in  renal  cases. 
It  will  often  be  found,  however,  I  think,  that  suff"erers  from  primary  I 
high  tension  have  always  been  abstemious  people,  and  for  such,  of] 
course,  dietetic  rules  are  of  no  use. 


5.  Renal  Disease. 

In  the  dietetic  treatment  of  renal  disease  the  principles  chiefly  to^ 
be  borne  in  mind  are :  (i)  To  diminish  the  amount  of  work  thrown] 
upon  the  kidneys ;  (2)  to  avoid  all  ingredients  in  the  food  which,! 
during  their  excretion,  are  calculated  to  irritate  the  diseased  organs. 

I.  As  the  kidneys  are  the  chief  route  for  the  excretion  of  thai 
products  of  nitrogenous  waste,  the  former  of  these  principles  involves 

*  See  King  Chambers,  '  Lectures,  chiefly  Clinical,'  lecture  xxiv. 


DIEl   IN  RENAL  DISEASE  541 

that  the  diet  should  be  not  too  rich  in  proteins,^  and  should,  as  far 
as  possible,  be  free  from  nitrogenous  extractive  matters. 

We  shall  see  immediately,  however,  that  as  regards  chronic  renal 
disease,  at  any  rate,  the  former  of  these  indications  must  sometimes 
be  overridden  by  more  pressing  considerations.  The  amount  of 
salt  in  the  food  should  also  be  diminished  as  far  as  possible,  for  the 
burden  of  excreting  it  falls  entirely  upon  the  kidneys. 

2.  Amongst  the  substances  calculated  to  irritate  the  kidney  in  the 
process  of  their  execretion  are  such  articles  as  spices,  mustard,  pepper, 
curry,  ginger,  radishes,  and  perhaps  asparagus.  Alcohol,  especially 
in  concentrated  forms,  is  also  strongly  contra-indicated  in  most  cases 
of  renal  disease  for  the  same  reason,  and  of  non-alcoholic  beverages 
ginger  ale  should  be  avoided,  owing  to  the  fact  that  it  contains  either 
ginger  or  capsicum  or  both. 

In  acute  renal  disease  an  exclusively  milk  diet  is,  by  common 
consent,  the  best  method  of  treatment.  That  this  is  not  a  mere 
general  impression  is  proved  by  the  fact  that  in  such  cases  a  milk 
diet  is  found  to  increase  the  elimination  of  urea  and  other  solids,  and 
to  decrease  the  amount  of  albumin  in  the  urine.  It  must  be 
remembered,  however,  that  milk  is  a  bulky  food,  and  by  introducing 
much  fluid  into  the  circulation  it  increases  vascular  tension,  throws 
a  strain  upon  the  heart,  and  aggravates  the  tendency  to  dropsy. 
The  quantity  allowed  should  therefore  be  restricted  to  three  pints 
a  day,  and  the  nutritive  value  of  the  diet  raised  by  the  addition  of 
cream  or  other  fatty  food,  or  by  allowing  moderate  quantities 
of  one  of  the  more  starchy  cereals,  such  as  rice. 

The  milk  may  be  given  either  plain  or,  what  is  better,  diluted  with 
some  alkaline  mineral  water,  and  if  the  patient  tires  of  it  kephir,  or 
butter-milk  may  be  used  as  a  partial  substitute. 

The  beneficial  effects  of  milk  cannot  be  altogether  due  to  the  fact 
that  it  is  poor  in  proteins.  As  a  matter  of  fact,  relative  to  its  other 
constituents,  milk  contains  a  very  considerable  proportion  of  nitrogen. 
It  is  not  improbable  that  its  advantages  are  to  be  partly  attributed  to 
the  chemical  peculiarities  of  casein,  and  to  the  fact  that  on  a  milk 
diet  intestinal  putrefaction  is  reduced  to  a  minimum.  The  addition 
to  the  milk  diet  of  substances  containing  only  carbohydrates  and  fats, 

1  The  belief  that  a  liberal  supply  of  protein  is  required  in  renal  disease  in 
order  to  make  good  the  albumin  excreted  in  the  urine  is  baseless.  Assuming 
an  average  excretion  of  ^  per  cent,  albumin,  the  daily  loss  would  not  amount  to 
more  than  8  grammes,  and  would  be  covered  by  the  protein  contained  in  the 
whites  of  two  eggs. 

a  See  Ralfe,  Tmns,  0/ the  Med.  Soc,  1894,  xvii.  251. 


543 


FOOD  AND  DIETETICS 


as  above  recommended,  is  open  to  no  theoretical  objection,  and 
might  perhaps  be  more  extensively  adopted  in  practice. 

In  subacute  nephritis  the  prolonged  nature  of  the  complaint 
necessitates  a  more  solid  diet.  The  principle  of  keeping  the  propor- 
tion of  protein  as  low  as  possible  (certainly  not  more  than  loo  grammes 
daily)  must  still,  however,  be  maintained.  The  more  nearly  the  case 
stands  to  the  acute  form  the  more  extensively  should  milk  be  used 
as  the  chief  source  of  protein,  but  in  the  more  chronic  forms  of  the 
disease  other  animal  foods  may  be  allowed  in  small  quantity.  It  is 
the  custom  to  select  from  these  the  white  meats,  such  as  fish,  chicken 
and  veal,  as  preferable  to  the  dark  meats.  This  preference  is  based 
upon  the  belief  that  the  former  contain  less  nitrogenous  extractive 
matter  than  the  latter.  That  this  is  true  as  a  chemical  fact  has  been 
denied  by  Von  Noorden  and  others,^  and  recently  the  matter  has 
been  put  to  a  practical  test  by  Pabst.^ 

He  compared  the  amount  of  albumin  in  the  urine  of  patients  with 
subacute  nephritis  (large  pale  kidney)  on  (i)  milk  diet,  (2)  a  diet 
containing  ^  pound  of  chicken  or  veal,  (3)  a  diet  containing  a  similar 
quantity  of  ordinary  meat,  with  the  following  results  : 

AVERAGE  DAILY  EXCRETION  OF  ALBUMIN. 


First  Case. 

First 
Experiment. 

Second 
Experiment. 

Second  Case. 

Milk 

White  meat 

Milk 

Ordinary  meat 

Milk 

Mixed  diet 

145 
130 
127 
129 
120 
130 

127 
II-4 
124 
109 
8-9 

12-9 
I2-I 
13-4 
131 
12  4 
122 

He  concludes  that  the  kind  of  diet  had  no  appreciable  or  constant 
influence  upon  the  composition  of  the  urine  or  the  amount  of 
albumin  which  it  contained.  Other  observers  have  obtained  similar 
results.^ 

It  must  be  remembered,  however,  that  the  white  meats,  and 
especially  fish,  are,  weight  for  weight,  poorer  in  protein  than  the 

1  See  Verhand  d.  I'jten  Cong.  j.  Inn.  Med.,  1899.  386,  and  Offer  and  Rosenquist, 
Berlin.  Klin.  Woch.,  1899,  xxxvi.  937,  968. 

Bokn.  Klin  Woch.,  1900,  xx.wii.  547.  For  earlier  experiments  of  a  similar 
kind,  see  a  paper  by  Hale  White  ('  On  the  Influence  of  Various  Diets  upon  the 
Composition  of  the  Urine  and  the  General  Condition  of  Patients  suffering  from 
Chronic  Bri^ht's  Disease')  in  the  Med.  Chir.  Trunsactions,  1894,  Ixxvi.  279. 

•"*  See  Kallmann  and  Mohr  '  Beitrage  zur  Diatetik  der  Nierenkrankheiten, 
Zeit.  f.  Klin.  Med.,  1902,  xliv.  441. 


CHRONIC  NEPHRITIS  543 

others,  and  therefore  if  one  wishes  to  keep  the  amount  of  nitrogenous 
matter  in  the  diet  low  there  may  still  be  advantage  in  having  recourse 
to  them,  although  it  must  be  admitted  that  the  recent  observations 
just  quoted  tend  to  show  that  the  dark  meats  may  not  be  so  harmful 
as  was  supposed,  provided  they  are  used  in  moderation.^  It  is 
probable,  too,  that  the  same  diet  may  not  suit  all  patients  equally 
well.  Sparks  and  Mitchell  Bruce,'  in  a  case  very  similiar  to  those  of 
Pabst,  certainly  found  that  milk  gave  better  results  than  anything 
else.  One  may  therefore  require  to  feel  one's  way  in  selecting  the 
most  suitable  diet. 

The  non-nitrogenous  constituents  of  the  diet  in  subacute  nephri  tis 
call  for  less  consideration.  Fats  and  carbohydrates  in  the  form  of 
cream,  cereals,  vegetables,  and  fruits,  may  be  freely  allowed,  but 
alcohol  and  all  irritating  substances  should,  as  in  all  renal  cases,  be 
avoided. 

In  arranging  the  diet  for  cases  of  chronic  nephritis,  regard  must  not 
be  paid  too  exclusively  to  the  requirements  of  the  kidney.  Important 
as  it  is  to  reduce  the  nitrogenous  waste  matters  in  the  urine  as  much 
as  possible,  this  must  not  be  done  at  the  expense  of  other  organs. 
The  maintenance  of  a  due  degree  of  cardiac  hypertrophy  and  increased 
vascular  tension,  which  are  essential  to  the  occurrence  of  proper 
excretion  in  chronic  renal  disease,  requires  that  the  amount  of  protein 
in  the  food  should  not  be  too  rigidly  limited.  On  the  other  hand,  an 
undue  increase  of  blood  pressure,  which  may  be  induced  by  a  too 
highly  nitrogenous  diet,  and  especially,  perhaps,  by  one  which  is  rich 
in  extractive  matters,  is  itself  a  source  of  danger,  as  predisposing  to 
arterial  degeneration  and  to  apoplexy. 

It  will  be  obvious  from  all  this  that  the  proper  dietetic  management 
of  a  case  of  chronic  Bright's  disease  often  requires  careful  steering. 
If  there  be  too  little  protein  in  the  food,  cardiac  compensation  may 
break  down  and  uraemia  result ;  if  there  be  too  much,  the  patient  is 
exposed  to  all  the  risks  and  inconveniences  of  excessive  vascular 
tension.  For  the  former  reason  milk  is  not  suited  to  constitute  the 
sole  source  of  protein  in  the  diet  of  such  cases ;  for  the  latter  the 
excessive  use  of  meat  is  also  to  be  deprecated.  As  a  general  rule, 
perhaps,  one  may  say  that  the  more  the  secreting  tubules,  as  opposed 
to  the  glomeruli,  are  involved,  the  less  protein  should  the  food  contain  ; 
but  for  the  majority  of  cases  the  most  appropriate  diet  is  that  re- 
commended for  gout,  i.e.,  one  which  is  only  moderately  rich  in  protein, 

^  See  also  Senator,  Berlin.  Klin.  Woch.  1899,  xxxvi.  990. 

'  Med.-Chir.  Trans.,  1879,  Ixii.  243  ;  see  also  Prior,  Zeii,  f.  Klin.  Med.,  1891, 
Kviii.  72. 


544  FOOD  AND  DIETETICS 

and  that  derived  largely  from  vegetable  sources,  and  from  which 
spices,  soups,  and  all  preparations  containing  the  extractives  of  meat 
are  excluded. 

In  cases  of  subacute  and  chronic  parenchymatous  nephritis  in 
which  dropsy  is  a  prominent  feature,  the  use  of  the  so-called  '  salt 
free '  diet  is  often  of  service.     It  is  described  in  detail  on  p.  556. 

Finally,  a  word  about  the  use  of  fluids  in  renal  disease.  It  was 
laid  down  as  a  rule  by  Bamberger  that  in  no  form  of  kidney  affection 
should  fluids  be  restricted  unless  diarrhoea  were  present.  Recently 
this  dictum  has  been  criticised  by  Von  Noorden,^  who  states  that  if 
dropsy  has  occurred,  and  the  secretion  of  urine  is  scanty,  great  benefit 
may  be  derived  from  limitation  of  fluids,  especially  if  there  be  cardiac 
dyspnoea  and  threatening  heart  failure.  He  says  that  long-continued 
observations  by  himself  and  his  assistants  have  quite  failed  to  show 
that  the  products  of  nitrogenous  waste  are  not  well  excreted  under 
such  a  plan,  and  cites  several  cases  in  which  it  wrought  great 
improvement.  On  the  other  hand,  he  recommends  that  if  diuresis 
has  already  set  in  fluids  should  be  freely  allowed,  even  although 
oedema  be  still  present.  It  must  remain  for  further  clinical  experi- 
ence to  substantiate  these  conclusions,  but  in  cases  of  high  vascular 
tension,  at  all  events,  the  sudden  entrance  of  a  considerable  quantity 
of  fluid  into  the  circulation  must  always  be  apt  to  be  injurious,  and 
in  such  circumstances,  whether  the  total  daily  supply  of  fluids  be 
limited  or  not,^  it  is  wise  to  forbid  the  consumption  of  a  large 
quantity  at  one  time. 

The  habitual  use  of  alcoholic  beverages  should  be  avoided  as  far 
as  is  practicable  in  cases  of  chronic  nephritis,  unless  they  are 
imperatively  indicated  for  the  sake  of  the  heart.  '  A  sufferer  from 
atrophic  nephritis,'  says  Von  Noorden,^  '  should  be  instructed  by 
his  physician  that  alcohol,  unless  prescribed  as  a  medicine,  is  for  him 
a  dangerous  poison.  If  he  insists  upon  taking  it,  he  does  so  at  his 
own  risk.' 

In  practice  these  principles  may  be  applied  in  the  following  rules: 

Directions  for  Diet  in  Chronic  Nephritis. 

I.  The  following  are  harmful  and  should  be  absolutely  avoided  : 

Soups  made  from  meat;  gravies;  sauces  ;  spices  {e.g.,  mustard,  pepper, 
ginger,  curry,  nutmeg  or  cloves). 

*  *  Diseases  of  Metabolism  and  Nutrition,'  Part  II.,  Nephritis.  English  edition 
{Bristol :  John  Wright  and  Co.,  1903). 

2  Von  Noorden  recommends  that  the  total  amount  of  fluid  allowed  in  the  diet 
in  cases  of  chronic  nephritis  should  not  exceed  i^  litres  (about  2  pints)  per  day. 
He  goes  so  far  as  to  say  that  in  many  cases  of  contracted  kidney  such  a  restric- 
tion may  save  life.  •  0/.  cit. 


DIET  IN  NERVOUS  DISEASES  545 

The  following  vegetables  : 

Radishes,  celery,  asparagus,  rhubarb. 
Alcoholic  beverages. 

2.  Tea  and  cofifee  should  be  taken  in  strict  moderation. 

3.  The  animal  ingredients  of  the  diet  should  be  restricted  to  i  egg,  i  pint  of 

milk,  one  helping  of  meat  (4  oz.)  and  one  of  fish  daily. 

4.  The  total  amount  of  liquid  taken  should  not  exceed  2  pints  daily. 

Diet  in  Diseases  of  the  Nervous  System. 

Dietetic  means  are  of  comparatively  little  value  in  the  treatment 
of  nervous  diseases.  In  most  of  such  cases  the  food  must  be  adapted 
to  the  condition  of  the  patient's  other  organs.  In  many  cases  ol 
neurasthenia  it  is  important  to  improve  the  state  of  the  patient's 
nutrition  by  adopting  the  plan  of  feeding  already  described  in  the 
section  on  'fattening  up'  (p.  511),  and  for  all  nervous  subjects  fat 
seems  to  be  one  of  the  most  important  nutritive  constituents  of  the 
food,  and  it  is  often  important  to  preach  to  such  patients  what  has 
been  described  as  '  the  gospel  of  fatness.'  The  question  of  the  most 
suitable  diet  in  cases  of  epilepsy  has  led  to  much  discussion,  some 
writers  recommending  abstention  from  meat  in  that  complaint,  whilst 
others  put  a  strict  bar  upon  the  use  of  alcohol, 

Schloss^  has  investigated  the  subject  afresh,  and  concludes,  as 
the  result  of  his  clinical  experiments,  that  the  nature  of  the  diet 
adopted  has  no  appreciable  influence  either  on  the  number  or  the 
severity  of  the  fits.  Nor  did  he  find  that  the  use  of  alcohol  could  be 
shown  to  be  in  any  way  harmful.  The  value  of  reducing  the  amount 
of  common  salt  in  the  diet  of  epilepsy  and  of  substituting  for  it 
bromide  preparations  has  also  been  insisted  upon  by  some  writers.^ 
Schloss,  in  investigating  this  point,  found  that  by  selecting  a  diet 
containing  but  little  sodium  chloride  he  could  reduce  the  consump- 
tion of  that  salt  to  about  30  grains  a  day,  replacing  it  by  60  grains  of 
mixed  bromides.  Under  this  treatment  the  fits  became  fewer  and 
less  severe,  but  the  patient  steadily  went  down  in  weight  and 
strength. 

Aldren  Turner'  believes  that  a  purin-free  diet  (p.  551)  is  sometimes 
useful  in  epilepsy,  especially  in  recent  cases  in  which  the  seizures 
are  of  the  major  variety.     It  is  certainly  always  worth  trying. 

1  '  Ueber  den  Einfluss  da  Nahrung  auf  den  Verlauf  der  Epilepsie,"  Wiener 
Klin.  Woch.,  1901,  xiv.,  No.  46. 

*  See  Balint  in  Berlin.  Klin.  Woch.,  1901,  xxxviii.  617.  A  review  of  other 
results  v,-ill  be  found  in  an  article  by  Dr.  Purves  Stewart  in  the  Med.  Annual  for 
1904  (p.  314). 

^  Proftitioner,  1906,  Ixxvi.  476. 

35 


546  FOOD  AND  DIETETICS 

In  cases  of  chorea  the  diet  should  be  of  a  fattening  character 
(p.  511),  cream  and  other  fat-containing  foods  being  given  Uberally. 
Where  fluid  food  can  alone  be  taken,  milk,  beaten-up  eggs,  and 
strong  soups  should  form  the  basis  of  the  diet.  These  constituents 
may  be  enriched  by  the  addition  of  casein  preparations,  cream,  and 
some  of  the  numerous  cereal  foods. 

In  Graves'  disease  there  is  some  reason  to  believe^  that  meat  is 
harmful,  and  a  vegetarian  or  lacto-vegetarian  diet  gives  the  best 
results.  The  food  should  be  nourishing  and  contam  plenty  of  fat. 
Alcohol,  tea  and  coffee  should  be  avoided. 

In  the  treatment  of  headaches — especially  of  the  periodic  migrainous 
or  bilious  variety — diet  is  sometimes  of  great  help.  In  certain  in- 
dividuals, particular  articles  of  food  may  apparently  cause  such 
headaches  by  acting  as  direct  poisons.  Amongst  such  articles  are 
tea,  sugar  and  eggs.  IMore  often  it  is  necessary  to  make  radical 
alterations  in  the  diet  as  a  whole.  In  well-nourished  patients  a 
decided  limitation  of  the  '  carbonaceous '  foods  as  recommended  by 
Dr.  flare  (for  details  see  p.  552)  is  often  successful.  Others  do  well 
— for  a  time  at  least — on  a  purin-free  diet  (p.  550).  In  yet  others, 
vegetarianism,  or  at  all  events  a  great  reduction  in  the  intake  of 
animal  protein  (meat)  on  the  lines  advocated  by  Chittenden,  gives 
good  results.  In  every  case  it  is  necessary  to  individualize,  and  to 
take  into  consideration  the  condition  of  the  vital  organs  and  the  state 
of  the  patient's  general  nutrition,  for  in  some  cases — particularly 
when  the  headache  is  of  a  neuralgic  character — a  cure  only  results 
when  the  level  of  nutrition  has  been  raised  by  a  judicious  course  of 
fattening  (p.  511). 

Diet  in  Diseases  of  the  Skin. 

There  are  four  ways  in  which  diet  may  conceivably  influence  the 
skin  :2  (i)  By  affecting  general  nutrition  ;  (2)  reflexly  from  the 
alimentary  canal  ;  (3)  by  giving  rise  to  the  absorption  into  the  blood 
of  irritating  or  decomposition  products ;  (4)  by  the  elimination 
through  the  skin  of  certain  constituents  of  the  food. 

It  must  be  admitted,  however,  that  when  we  come  to  use  dietetic 
methods  in  the  actual  treatment  of  cutaneous  disorders,  we  find  our- 
selves greatly  hampered  both  by  our  ignorance  of  the  precise  part 
played  by  diet  in  any  given  case,  and  by  the  always  unknown  factor 
of  personal  idiosyncrasy.     So  much  is  this  the  case  that  it  may  be 

-  Hanna  Thomson,  Amtr.  Journ.  Med.  Set.,  1908,  cxxw.  313. 
*  Walter  Smith,  Brit.  Journ  0/ Dermat.,  1898,  vii.  328 


DIET  IN  DISEASES  OF  THE  SKIN  547 

said  without  fear  of  contradiction  that  there  are  but  few  diseases  of 
the  skin  in  which  treatment  by  diet  is  of  much  value,  and  that  the 
potentiahties  of  this  Hne  of  attack  are  much  less  promising  than 
patients  generally  believe. 

In  the  great  majority  of  cases  of  skin  disease,  therefore,  either  no 
special  rules  of  diet  are  required,  or  they  must  be  drawn  up  with  refer- 
ence to  the  patient's  general  condition  without  regard  to  the  state  of 
the  skin.  There  are  a  few  cutaneous  diseases,  however,  in  which 
diet  may  be  of  some  direct  help,  and  these  may  be  briefly  considered. 

Eczema. — In  very  acute  cases  in  which  the  patient  is  really  ill,  an 
exclusively  milk  diet  may  be  required  for  a  time,  and  in  any  case  the 
more  marked  the  local  inflammatory  signs  are,  the  simpler  should 
the  diet  be.  In  chronic  cases  it  is  customary  to  forbid  sugar  and  to 
recommend  a  liberal  use  of  green  vegetables,  but  in  both  instances 
on  no  very  satisfactory  grounds.  An  excess  of  salt  also  appears  to 
be  injurious.  On  the  Avhole,  the  diet  in  chronic  eczema  should 
conform  to  the  principles  of  -simplicity  and  temperance,'  and  may, 
in  details,  be  the  same  as  for  chronic  gout  (p.  518).  Alcohol  is 
usually  harmful. 

In  psoriasis  various  *  systems '  of  diet  occasionally  meet  with 
success.  Bulkleyi  recommends  absolute  vegetarianism,  forbidding 
even  milk  and  eggs,  and  says  he  has  seen  the  worst  cases  disappear 
under  such  a  plan,  whilst  per  contra  the  quite  opposite  regimen  of 
meat  and  hot  water  only ,2  or  an  exclusively  milk  diet,  has  proved 
successful  in  the  hands  of  others.  In  the  majority  of  cases,  diet  has 
probably  little  or  no  influence. 

In  rosacea  the  diet  should  be  arranged  to  meet  any  form  of 
dyspepsia  which  may  be  present  (p.  529),  but  alcohol,  tea,  coffee, 
spices,  and  anything  which  causes  flushing  of  the  face  must,  be 
rigidly  excluded. 

In  pruritus,  especially  of  the  anus  or  vulva,  all  highly-seasoned, 
salted,  or  preserved  foods  should  be  avoided,  besides  alcohol  and 
coffee,  and  the  diet  restricted  to  the  white  meats,  toast,  green 
vegetables,  and  light  milk  puddings.  Should  diabetes  be  present, 
the  dietetic  indications  are,  of  course,  the  same  as  for  that  disease 
(p.  488). 

In  urticaria  much  may  be  effected  by  diet  if  one  can  discover- 
not  always  an  easy  task — the  peccant  ingredients  of  the  food. 
Amongst  the   most   frequent  offenders   are   shell-fish,   mushrooms, 

1  Jlviii.  Auiey.  Med.  Assoc,  1908,  February  22. 

•  Parkes,  Lancet,  1S74,  i.  722  ;  and  Malcolm  Morris,  Practitioner,  1906,  Ixxvi.  575. 


548  FOOD  AND  DIETETICS 

pickles,  pork,  eggs,  cheese,  oatmeal,  strawberries  or  other  fruits,  and 
sour  wines,  but  almost  any  article  of  food  may  cause  it  if  an 
idiosyncrasy  be  present.  I  have  also  known  patients  to  be  cured  by 
adopting  vegetarianism  for  a  time. 

In  concluding  this  section,  one  cannot  do  better  than  quote  the 
wise  words  of  an  eminent  dermatologist:^  '  After  all,  it  is  in  com- 
paratively few  cases  of  skin  disease  that  the  diet  is  really  of  any 
particular  importance.  .  .  .  Put  not  your  faith  in  printed  dietaries, 
or  indeed  in  any  general  formularies.  Above  all,  remember  that  the 
patient  has  larger  and  better  opportunities  of  observation  than  the 
doctor,  and,  if  he  is  a  person  of  ordinary  intelligence  and  self-control, 
he  should  be  trusted.  The  doctor  Avho  attempts  to  dictate  as  an 
oracle  in  the  matter  of  diet  is  like  Lord  Foppington's  bootmaker, 
who  insisted  that  he  knew  better  than  his  client  whether  or  not  the 
shoe  pinched.' 

^  Malcolm  Morris,  loc.  at.,  p.  584. 


t  549  ] 


CHAPTER  XXIX 

SOME  DIETETIC  '  CUEES '  AND  'SYSTEMS* 

In  the  earlier  part  of  this  book  reference  has  been  made  to  the 
so-called  milk  (p.  130),  whey  (p.  132),  koumiss  (p.  143),  and  grape 
(p.  256)  '  cures.'  In  the  present  chapter  I  propose  to  deal  briefly 
with  some  of  the  more  elaborate  '  systems '  of  diet  which  are  some- 
times useful  in  the  treatment  of  disease.  That  such  systems  are 
occasionally  of  great  therapeutic  value  no  one  can  deny,  but  they 
must  be  used  discreetly,  bearing  in  mind  the  dangers  and  fallacies 
inherent  in  all  attempts  to  treat  disease  on  a  '  system,'  regardless  of 
the  peculiarities  of  the  individual  case,  and  remembering  that  no 
such  system  can  ever  be  a  panacea,  but  is  at  best  of  restricted,  and 
often  only  of  temporary,  value.  The  reckless  and  uncritical  advocacy 
of  the  faddist  can  only  serve  to  bring  such  systems  into  disrepute. 

Vegetarian  and  Lacto-vegetarian  Diet, 

In  a  previous  chapter  (p.  172)  the  question  of  vegetarianism  was 
discussed  in  detail,  and  the  conclusion  arrived  at  that  it  was  not 
a  form  of  diet  which  is  to  be  unreservedly  commended  for  healthy 
persons.  None  the  less,  as  a  mode  of  treatment  in  certain  cases 
of  disease,  such  a  regimen  is  deserving  of  the  careful  consideration  of 
the  medical  profession,  and  all  the  more  that  hitherto  it  has  been 
mainly  exploited  by  the  large  body  of  '  amateur  '  practitioners. 

There  are  certain  well-recognized  peculiarities  and  properties  of 
a  non-flesh  diet  which  justify  the  expectation  that  it  will  prove  of 
use  in  some  morbid  states.  In  the  first  place,  such  a  diet  is  compara- 
tively free  from  the  purin-bodies,  the  share  of  which  in  the  produc- 
tion of  gout  has  already  been  discussed  (p.  517),  besides  containing 
almost  always  less  total  protein  than  a  mixed  diet.  In  the  second 
place,  a  diet  from  which  flesh  is  excluded,  and  which  contains  a  large 
proportion  of  milk,  tends  greatly  to  restrain  the  process  of  putrefac- 


550  FOOD  AND  DIETETICS 

tion  in  the  intestine.  Now,  there  is  some  reason  to  believe  that 
certain  obscure  conditions  of  general  ill-health,  and  in  particular 
some  cases  of  neurasthenia,  are  produced  and  maintained  by  the 
absorption  of  such  putrefactive  products.  In  the  third  place, 
such  a  diet  is  peculiarly  rich  in  mineral  salts,  and  although  the  part 
played  by  these  in  metabolism  is  at  present  but  ill-understood,  there 
is  yet  reason  to  believe  that  by  altering  the  '  balance  *  of  the  salts  in 
the  body  nutrition  may  sometimes  be  influenced  for  good.  In  the 
last  place,  a  diet  which  is  of  mainly  vegetable  composition  leaves 
a  large  residue  in  the  bowel,  and  so  tends  to  counteract  the  prevail- 
ing modern  tendency  to  constipation,  with  all  its  attendant  evils. 

Much  careful  observation  and  clinical  experiment  will  certainly  be 
required  before  we  are  able  clearly  to  discern  exactly  in  what  cases 
a  diet  of  this  sort  is  likely  to  be  of  benefit,  but  meantime  the  follow- 
ing list  of  diseases  in  which  there  is  at  least  presumptive  evidence 
that  a  vegetarian  or  lacto-vegetarian  regimen  exercises  a  curative 
influence  may  be  tentatively  put  forward.^ 

(i)  Corpulence  complicated  by  constipation  in  middle  life. 

(2)  Certain  cases  of  alcoholism. 

(3)  Some  forms  of  functional  dyspepsia  and  intestinal  aff"ections  of 
nervous  origin. 

(4)  Idiopathic  neuralgias  and  those  having  a  gouty  basis. 

(5)  Headaches  and  other  disorders  dependent  on  constipation  in 
neurasthenic,  hysterical,  and  epileptic  patients. 

(6)  Conditions  of  abnormal  irritability  of  the  heart  of  nervous 
origin  and  in  exophthalmic  goitre ;  but  not  heart-weakness  due  to 
arteriosclerosis  and  myocarditis. 

(7)  Many  cases  of  nervous  insomnia. 

(8)  Some  varieties  of  disease  affecting  the  skin. 

It  is  almost  always  advisable  to  make  the  change  from  an  ordinary 
diet  gradually,  and  in  many  cases  it  is  inadvisable  to  continue  the 
vegetarian  plan  for  longer  than  six  weeks  at  a  time. 

The  Purin-Free  Diet. 

Purins  are  a  series  of  bodies  which  contain  the  nucleus  CgN^,  and 
which  on  oxidation  yield  two  molecules  of  urea.  They  may  be 
classified  as:  (i)  Oxy-purins  (hypoxanthin,  xanthin  and  uric  acid); 
(2)  amino-purins  (adenin  and  guanin) ;  (3)  methyl-puvins  (theobromin 
and  caffein). 

The   purins   of  the   food   (exogenous   purins)  are  taken   in   the 

1  See  L.  Kuttner,  Berliner  Klinik,  January,  1902,  and  Albu,  '  Die  Vegetarische 
Dial '  (Leipzig,  Georg  Thieme,  1902),  p.  130. 


THE  PURIN-FREE  DIET  551 

following  forms:  (i)  MethyUpurins  in  tea,  coffee  and  cocoa  ;  (2)  free 
purins,  such  as  xanthin  and  hypoxanthin,  in  meat  extract ;  (3)  bound 
Purins  in  the  nucleo-proteins  of  many  animal  and  some  vegetable 
foods. 

Foods  may  be  classified  according  as  they  are  rich  in  purins,  poor 
in  them,  or  free  from  them,  as  follows  : 

1.  Rich  in  purins :  Sweetbread,  liver,  beef,  pork,  mutton,  chicken* 
veal,  salmon,  halibut,  and  plaice. 

2.  Poor  in  purins :  Potatoes,  onions,  oatmeal,  the  pulses,  turnips, 
carrots,  parsnips,  asparagus,  rhubarb,  sea-kale,  spinach,  dates,  figs, 
codfish,  and  sole. 

3.  Free  from  purins  :  Milk,  eggs,  cheese,  butter,  sugar,  white 
bread,  rice,  tapioca,  cabbage,  cauliflower,  lettuce,  macaroni,  straw- 
berries. 

Amongst  beverages,  tea,  coffee,  and  cocoa,  and  malt  liquors  contain 
purins  ;  wines  and  spirits  are  free  from  them. 

A  diet  which  is  practically  purin-free  may  therefore  be  constructed 
by  observing  the  following  rules  :^ 

Directions  for  a  Pdrin-freb  Diet. 

1.  The  things  to  be  avoided  are  : 

(a)  All  flesh  foods  (meat,  fish,  fowl,  game,  etc.)  and  articles  derived  from 

them  (e.g..  soups,  sauces,  gravies). 

(b)  Peas,  beans,  lentils,  oatmeal,  asparagus,  onions. 

(c)  Tea,  coffee  and  malt  liquors. 

2.  The  diet  should  be  composed  of  vegetable  foods  (except  those  mentioned 

above),  milk,  cheese  and  eggs. 

The  following  is  suggested  as  a  daily  menu  : 

Breakfast :  Epgs,  the  fat  of  bacon  (avoiding  all  lean),  bread  or  toast, 
milk  flavoured  with  cocoa  or  a  dash  of  coffee  or  tea.  Any  fruit,  stewed 
or  fresh. 

Luncheon  or  dinner  •  Soup  made  from  vegetables  (except  those  men- 
tioned above),  with  the  addition  of  milk,  if  desired,  and  thickened 
with  some  farinaceous  preparation  or  grated  cheese ;  one  of  the 
Italian  dishes — e.g.,  risotto,  macaroni,  spaghetti,  or  polenta  ;  potatoes 
in  any  form  ;  any  simple  pudding  or  stewed  fruit ;  cheese  ;  salad. 

The  change  to  such  a  diet  should  be  made  gradually  For  a  week 
or  two  the  non-nutritious  purin-containing  articles — e.g.,  tea,  coffee, 
soups,  beef- extracts,  gravies — should  be  avoided,  and  meat  and  fish 
taken  only  once  a  day.  After  this  probationary  period  is  over  the 
more  strict  diet  may  be  adopted. 

The  advantages  of  what  was  practically  a  purin-free  diet  in  cases 
of  gout  were  pointed  out  long  ago  by  Dr.  George  Cheyne,^  but  m 

'  The  construction  of  such  a  diet  is  facilitated  by  a  study  of  various  cookery- 
books — e,g.,  'Vegetarian  and  Simple  Diet,'  by  Kenney  Herbert  (Sonnenschein), 
and  '  The  Apsley  Cookery-Book  '  (J.  and  A.  Churchill). 

*  '  The  English  Malady  '  (London.  1733). 


552  FOOD  AND  DIETETICS 

recent  times,  and  under  its  modern  title,  it  has  been  specially 
advocated  by  Dr.  Haig.^  The  benefits  derived  from  its  use  in 
certain  cases  of  disease  are  ascribed  to  the  alleged  toxicity  of  purins, 
which  are  believed  to  produce  the  following  amongst  other  diseases : 
Chronic  and  irregular  gout  in  all  its  manifestations,  chronic  '  rheu- 
matism,' migraine  and  periodic  headaches,  asthma,  bilious  attacks, 
epilepsy,  catarrhs,  neurasthenia  and  general  ill-health  of  indefinite 
nature. 

It  would  be  going  far  beyond  the  province  of  this  book  to  discuss 
in  detail  the  evidence  for  and  against  the  harmfulness  of  the  purin- 
bodies  in  food-stuffs, ^  but  it  may  be  said  that  whilst  there  can  be  no 
doubt  of  the  fact  that  a  purin-free  diet  is  capable  of  exerting  a 
curative  effect  in  some  at  least  of  the  above-mentioned  maladies, 
there  is  equally  little  doubt  that  the  therapeutic  claims  made  for  it 
by  some  of  its  more  intemperate  advocates  cannot  be  substantiated. 
There  is  certainly  no  reason  to  believe  that  purins  are  *  poisonous  * 
in  any  real  sense  of  the  term  to  the  vast  majority  of  mankind,  and, 
on  the  other  hand,  it  is  quite  possible  that  some  of  the  good  effects 
which  a  purin-free  diet  is  capable  of  producing  are  to  be  ascribed  to 
something  other  than  its  poverty  in  these  chemical  compounds.  As 
it  is  quite  conceivable,  however,  that  some  persons  have  a  metabolic 
idiosyncrasy  to  purins,  and  that  in  such  they  produce  disease,  the 
purin-free  diet  is  always  worth  trying  in  chronic  and  intractable 
cases  of  the  type  already  referred  to.  It  will  often  be  found,  how- 
ever, that  even  in  such  persons  freedom  from  symptoms  is  not 
permanent,  but  that  the  morbid  manifestations  recur  after  a  time, 
although  perhaps  in  a  milder  form.''  In  any  case,  the  change  to 
such  a  diet  should  always  be  made  cautiously,  and  it  is  not  often 
advisable  to  continue  it  for  long  in  its  strict  form,  as  otherwise 
digestive  troubles  and  impairment  of  the  general  health  are  apt  to 
result. 

Dr.  Hare's  System. 

Dr.  Francis  Hare*  believes  in  the  possibility  of  the  accumulation 
in  the  blood  of  an  excess  of  '  fuel '  or  '  carbonaceous  '  material.     He 

^  'Diet  and  Food  '  (London  :  Churchill),  etc. 

^  The  question  is  discussed  in  the  following  amongst  other  papers :  Potts. 
'The  Advantages  of  a  Purin-Free  Diet,'  Lancet,  1905,  i.  1636;  *  Purin-Free 
Dietaries,'  Brit.  Med.  Journ.,  1909,  i.  no;  Chalmers  Watson,  'Has  a  Purin- 
Free  Dietary  any  Special  Therapeutic  Value,'  ibid.,  1907,  ii.  1759  ;  Bryce,  '  The 
Limitations  of  a  Purin-Free  Diet,'  ibid.,  October,  31,  1908. 

*  See  Bryce,  loc.  cit. 

*  '  The  Food  Factor  in  Disease'  (Longmans,  1905),  and  '  The  Dietetic  Treat- 
ment of  Certain  Diseases  in  the  Well -nourished  and  Corpulent '  {The  Medical 
Magazine,  1907,  xvi.  722J. 


DR.  HARE'S  SYSTEM  553 

terms  this  a  state  of  hyperpyramia,  and  attributes  to  it  the  occurrence 
of  many  periodic  disorders,  such  as  migraine,  bilious  attacks,  and 
asthma.  The  hyperpyraemic  state  can  be  prevented  by  reducing  the 
intake  of  carbonaceous  food,  with  the  consequence  that  the  periodic 
disorder  disappears. 

He  begins  by  placing  the  patient  on  a  small,  mainly  protein  diet, 
consisting,  say,  of  8  to  12  ounces  of  cooked  lean  meat  or  fish,  with 
I J  ounces  of  bread  or  toast  and  a  little  butter;  green  non-starchy 
vegetables  are  permissible,  also  tea  and  coffee  with  a  little  milk  but 
no  sugar.  Such  a  diet  is  usually  accompanied  by  loss  of  weight. 
The  loss  is  carefully  estimated  by  frequent  weighings  and  by  slowly 
adding  to  the  amount  of  carbohydrates  and  fats,  preferably  by 
cautiously  increasing  the  allowance  of  bread,  butter,  and  milk  a  diet 
is  arrived  at  under  which  the  weight  remains  stationary  and  carbon 
equilibrium  is  being  maintained  on  a  minimum  intake.  In  arriving 
at  this  minimum  exactitude  is  indispensable  ;  the  scale  of  diet  should 
be  fully  written  out  and  the  ingredients  weighed. 

If  one  is  treating  a  case  of  migraine  it  is  advisable  to  begin  the 
diet  about  a  fortnight  before  the  next  attack  is  expected,  and  after 
one  headache  period  has  been  passed  to  increase  slowly  the  amount 
of  starchy  food  until  the  weight  is  stationary. 

Without  accepting  the  theoretical  considerations  upon  which  thi*k 
system  of  treatment  is  based  one  may  freely  admit  that  it  gives 
excellent  results  in  many  of  the  conditions  referred  to,  and  as  it  is 
easy  to  carry  out  it  is  often  a  valuable  resource.  Such  a  regimen, 
however,  is  only  suitable  in  well-nourished  persons,  and  it  is  in  these 
that  its  most  striking  effects  are  obtained. 

Exclusive  Protein  Diet. 

In  this  system,  which  is  better  known  as  the  Salisbury  cure,i  the 
diet  consists  of  lean  meat  and  hot  water  only.  Such  a  diet  may  be 
spoken  of  as  an  exclusively  protein  one,  for  although  there  is  always 
a  certain  proportion  of  fat  even  in  lean  meat,  yet  the  amount  for 
practical  purposes  is  negligible.  This  system  has  been  recom- 
mended in  the  treatment  of  chronic  articular  gout,  some  diseases  of 
the  skin — e.g.,  psoriasis — and  in  certain  intractable  forms  of  dys- 
pepsia, especially  when  associated  with  atonic  dilatation  of  the 
stomach.  The  following  is  a  description  of  the  technique  of  the  diet 
as  given  by  one  of  its  more  recent  advocates  i^ 

1  Salisbury,  'The  Relation  of  Alimentation  and  Disease,'  New  York,  1S95, 
•  Eroest  Young,  The  Clinical  Journal,  1908,  xxxiii.  55. 


554  FOOD  AND  DIETETICS 

*  The  basis  of  the  diet  is  thoroughly  cooked  minced  lean  beef  (so 
prepared  that  all  gristle  and  the  greater  part  of  the  connective  tissue 
are  removed)  and  hot  water.  (Minced  mutton  or  chicken  may  be 
substituted  occasionally  for  variety,  but  bulk  for  bulk  neither  is  so 
nourishing  as  the  beef.) 

'  The  minced  beef  is  given  three  times  a  day,  with  a  five-hourly 
interval  between  each  meal.  The  best  hours  for  meals  are  8.30  a.m., 
1.30  p.m.,  and  6.30  p.m.  In  any  case  the  last  meal  should  not  be 
later  than  7  p.m. 

'  The  hot  water  is  given  four  times  a  day,  one  and  a  half  to  one 
and  a  quarter  hours  before  each  meal,  and  three  and  a  half  hours 
after  the  last  meal.  The  water  should  be  sipped  slowly  at  a  tempera- 
ture of  about  120°  F. — roughly  that  at  which  tea  or  coffee  is  usually 
taken.  The  quality  of  the  water  is  an  important  factor,  and  if  at 
all  hard  distilled  water  must  be  used. 

•  The  quantity  of  meat  at  each  meal  varies  from  2  ounces  upwards, 
the  quantity  of  each  portion  of  hot  water  being  a  pint,  or  less, 
according  to  the  nature  of  the  individual  case.' 

The  following  details  as  to  the  preparation  of  the  diet  (from  the 
same  author)  may  be  of  practical  help : 

The  diet  may  be  taken  in  the  form  of  beef  mince  or  beef  cakes,  the  former 
being  rather  more  digestible  but  less  satisfying  than  tlie  latter. 

Both  should  be  prepared  from  '  topside '  steak,  preferably  from  the  centre  of 
the  round  of  beef. 

1.  The  Beef  Mince. — Take  a  steak,  not  less  than  an  inch  thick,  free  it  from  fat, 
place  in  a  frying-pan — previously  rubbed  with  a  little  butter  to  prevent  sticking 
— and  cook  quickly  (turning  occasionally)  over  a  clear,  sharp  fire  until  it  is  almost 
ha!/  done.  Allow  it  to  cool,  then  cut  into  strips  and  pass  three  or  four  times 
through  an  '  Enterprise '  mincer.  Place  the  minced  meat  in  an  enamelled  or 
aluminium  saucepan,  add  a  little  water  (about  a  teaspoonful  to  i  ounce  of  meat 
is  the  average  quantity)  and  beat  to  a  smooth,  stiff  pulp  with  a  wooden  spoon  ; 
it  must  never  be  watery.  Place  the  saucepan  on  an  asbestos  cooking-mat  upon  a 
cool  part  of  the  stove  and  cook  slowly,  stirring  and  turning  over  the  mince 
constantly  until  the  red  colour  disappears  and  it  is  thoroughly  brown.  This  will 
take  from  fifteen  to  twenty  minutes  for  a  small  quantity.  If  properly  prepared  at 
a  gentle  heat,  the  mince  will  be  quite  smooth  and  of  the  consistency  of  soft  dough. 
If  it  is  granular,  it  shows  it  has  been  cooked  too  quickly,  and  must  be  rejected. 

2.  The  Beef  Cahes. — Pass  strips  of  raw  steak  three  or  four  times  through  the 
mincer.  Place  the  minced  meat  on  a  plate,  flatten  out  with  a  fork,  and  add  a 
little  water.  By  means  of  two  forks  quickly  shape  the  meat  into  a  round,  flat 
cake  about  i  inch  thick,  touching  the  meat  as  lightly  as  possible,  just  sufficient 
to  make  it  hold  together.  Place  the  cake  in  an  '  Enterprise'  griller,  previously 
rubbed  on  both  sides  with  a  little  butter.  Hold  the  griller  about  8  inches  above 
a  sharp,  clear  fire,  turning  it  about  every  ten  seconds  until  the  cake  is  cooked. 
The  time  required  for  cooking  is  seven  or  eight  minutes. 

Condiments,  such  as  pepper,  salt,  and  mustard,  may  usually  be  allowed,  unless 
hyperchlorhydria  is  a  prominent  feature. 

If  the  patient  complains  much  of  hunger,  a  few  spoonfuls  of 
beef-tea  or  a  piece  of  unsweetened  chocolate  may  be  given  two  and 


EXCLUSIVE  PROTEIN  DIET  555 

a  half  hours  after  each  meal.     A  cup  of  clear  tea  may  be  giveu  in 
place  of  some  of  the  afternoon  hot  water. 

The  theoretical  considerations  on  which  the  exclusive  protein  diet 
is  based  cannot  be  considered  here,  and,  indeed,  they  are  largely 
speculative  in  nature,  but  some  reference  to  the  subject  will  be  made 
later.  Meanwhile  it  need  only  be  said  that  the  treatment  un- 
doubtedly yields  good  results  in  some  of  the  chronic  disorders  of 
digestion  and  nutrition  already  indicated,  but  it  is  only  in  exceptional 
cases  that  it  is  required,  and  in  any  event  it  is  not  advisable  to 
continue  such  a  regimen  for  longer  than  six  weeks  at  a  time. 


The  reader  may  have  noticed  that  vegetarianism,  the  purin-free 
diet,  Dr.  Hare's  system,  and,  to  some  extent,  the  '  exclusive  protein 
diet '  are  all  recommended  by  their  supporters  in  very  much  the 
same  class  of  disorders,  and  it  may  seem  strange  that  systems  so 
opposed  should  be  capable  of  curing  identical  diseases.  In  these 
circumstances  one  naturally  looks  for  some  peculiarity  common  to 
all  the  systems  which  might  explain  this  apparent  contradiction.  I 
would  venture  to  suggest  that  this  may  be  found  in  the  fact  that 
they  all  tend  to  promote  a  more  complete  oxidation  of  the  proteins. 
Such  a  result  may  be  brought  about  either  by  lessening  the  total 
intake  of  protein  or  by  diminishing  the  protein  sparers  (especially 
the  carbohydrates)  which  interfere  with  their  complete  combustion. 
Now,  in  vegetarianism,  as  we  have  seen,  the  total  amount  of  proteid 
in  the  diet  is  apt  to  be  low,  and  the  same  is  true,  in  practice,  if  not 
in  theory,  in  the  case  of  the  purin-free  diet ;  in  Dr.  Hare's  system, 
on  the  other  hand,  and  still  more  in  the  case  of  the  exclusive  protein 
diet,  the  protein  sparers  are  greatly  reduced.  Whichever  of  these 
plans  is  adopted  then,  it  is  probable  that  the  oxidation  of  the  protein 
of  the  food  is  likely  to  be  more  complete  than  is  the  case  with  an 
ordinary  abundant  mixed  diet.  It  will  be  remembered  that  one  of 
the  advantages  claimed  for  the  Chittenden  diet  standard  is  that  it 
tends  to  promote  this  complete  utilization  of  proteins,  and  it  is  note- 
worthy that  the  advocates  of  Chittenden's  plan  claim  that  it  also  is 
capable  of  preventing  or  curing  much  the  same  class  of  diseases  as 
those  for  which  the  systems  of  diet  dealt  with  above  are  recom- 
mended. 

It  is  possible,  too,  that  any  marked  alteration  in  diet  is  capable  of 
effecting  an  improvement  in  general  health,  just  as  change  of  air 
doee,  and  in  ways  that  are  as  ill  understood. 


556  FOOD  AND  DIETETICS 

ZOMOTHERAPY.I 

By  the  term  *  zomotherapy '  (Zwjmos,  tneat-juice)  is  meant  treatment 
by  raw  meat  or  raw  meat-juice.  It  was  first  introduced  by  Professor 
Charles  Richet  in  igoo,^  and  was  based  on  the  successful  results 
obtained  by  feeding  dogs  which  had  been  inoculated  with  tuberculosis 
on  raw  meat,  although  Fuster  had  recommended  a  diet  of  raw  meat 
and  alcohol  in  tuberculosis  as  far  back  as  1865.  Subsequent  experi- 
ments showed  that  the  beneficial  properties  of  raw  meat  reside  in 
the  muscle-juice  and  not  in  the  fibres,  and,  further,  that  the  benefit 
derived  is  not  to  be  ascribed  to  hyper-alimentation,  inasmuch  as  (in 
dogs)  a  daily  dose  of  50  to  100  c.c.  of  the  juice  are  sufficient  to 
give  the  desired  results.  The  modus  operandi  of  raw  meat-juice  in 
the  cure  of  tuberculosis  is  not  understood,  but  it  has  been  suggested 
either  that  it  contains  a  specific  '  tonic '  and  stimulant,  or  that  it  acts 
in  virtue  of  the  presence  of  some  antitoxic  substance, 

Zomotherapy  is  indicated  in  cases  of  anaemia,  neurasthenia,  debility, 
convalescence,  and  latent,  incipient,  or  active  tuberculosis.  In 
carrying  it  out  the  juice  should  either  be  obtained  fresh  by  expies- 
sion^  from  the  best  rumpsteak  or  Carnine  Lefrancq  (p.  loi)  may 
be  used  instead.  The  fresh  raw  juice  may  be  given  in  quantities  of 
3  ounces  a  day  and  upwards,  preferably  in  tepid  beef-tea.  The  dose 
of  Carnine  Lefrancq  is  from  i  to  6  tablespoonfuls  daily,  given  alone 
or  mixed  with  any  other  liquid  (except  beef-tea),  either  cold  or 
slightly  warm. 

Salt-Free  Diet, 

The  average  amount  of  common  salt  in  an  ordinary  diet  is  about 
17  grammes  per  day,  and  although  it  is  impossible,  even  were  it 
desirable,  to  construct  a  genuinely  '  salt-free  '  diet,  yet  by  a  judicious 
selection  of  foods  it  is  easy  to  reduce  the  daily  intake  to  about 
2  grammes.  Such  a  limitation  of  salt  is  of  use  in  the  treatment  of 
dropsy,  particularly  the  dropsy  of  chronic  parenchymatous  nephritis. 
It  was  shown  by  Widal — to  whom  much  of  the  credit  of  introducing 
the  salt-free   diet   is   due — that   a   chronically  inflamed  kidney   is 

*  See  Hericourt,  'Zomotherapy.'     Paris:  J.  Ruefif. 

'  Comptes  Rmdus  de  I'Acadimie,  1900,  cxxx.  605. 

'  The  '  Hercules '  Meat-juice  Press  gives  the  best  yield.  It  can  be  obtained 
from  Messrs.  Shoolbred,  Whiteley,  or  Kent  (High  Holborn).  Philip  ('  Zomo- 
therapy in  Pulmonary  Tuberculosis,'  The  Practitioner,  1905,  Ixxiv.  14)  also  exhibits 
zomotherapy  in  the  form  of  '  raw-meat  soup  '  prepared  as  follows  :  Take  ^  pound 
of  finely-minced /y«/i  meat,  and  mix  in  a  bowl  with  sufficient  milk  to  produce  a 
thick,  uniform  paste.  Immediately  before  serving  add  \  pint  of  milk  at  150°  F. 
In  place  of  milk,  the  soup  may  be  made  in  similar  fashion  with  stock  of  beef,  or 
chicken,  or  veaU 


SALT -FREE  DIET 


557 


incapable  of  excreting  common  salt  freely.  The  salt  is  therefore 
retained  in  the  body,  and  in  order  that  the  normal  composition  of 
the  body. fluids  may  be  maintained  water  is  kept  back  also,  with  the 
result  that  dropsy  sets  in.  When  the  amount  of  salt  in  the  food  is 
reduced  the  percentage  of  it  in  the  blood  gradually  falls,  the  salt 
which  has  been  stored  up  in  the  dropsical  effusion  is  drawn  upon  to 
make  good  the  deficiency  in  the  blood,  and  with  its  withdrawal  the 
dropsy  subsides.  Such,  put  briefly,  is  the  rationale  of  the  plan  and 
of  its  success  in  cases  of  chronic  parenchymatous  nephritis, ^  and 
also,  though  less  conspicuously,  in  cardiac  dropsy,^  and  in  the 
ascites  of  cirrhosis^  there  can  no  longer  be  any  doubt. 

A  comparatively  salt-free  diet  is  not  difficult  to  construct.  It 
must,  of  course,  contain  no  added  salt.  Ordinary  bread,  salt  butter, 
sea-water  fish,  dried,  smoked,  salted  and  preserved  foods  and 
sauces  and  pickles  must  be  avoided.  Soups  should  be  made  from 
vegetables  and  milk.  Bread  must  be  baked  without  salt,  or  its  place 
taken  by  home-made  scones. 

The  following  table,  which  shows  the  amount  of  salt  per  1,000 

parts   in   some  common  articles  of  food,  will  be  of  assistance  in 

making  a  selection  :* 

Fresh  butter      ..        ..        I'o 
Peas        ..         ..         ..        o'6 

Meat o'3-i'o 

Potatoes  ..         ..        05 

Fresh-water  fish  ..        0-48 


Fruit o  •03-0*2 

Rice        0-02 


Ham 18 

Cheeae  ..         ..         ..  15 

Bacon 10 

Bread 8-10 

Sea-fish  ..         ..  5*4 

Milk i*5-2'5 

Eggs 1-6 

Lentils  . .  . .  . .  2  "3 

The  following  may  be  regarded  as  a  typical  bill  of  fare :" 

Breakfast :  An  egg,  bread  without  salt,  fresh  butter,  tea  or  cofi'ee  and  cream. 

10  a.m.  :  A  glass  of  milk. 

Dinner :  Chicken  or  fresh-water  fish  ;  potato  ;  jelly. 

3  p.m. :  A  gJass  of  milk. 

Supper:  An  egg,  chicken,  or  fresh-water  fish  ;  bread  without  salt;  custard; 

fresh  butter.  '' 

8  p.m.  :  A  glass  of  milk  or  water. 

Sour  Milk  Treatment.' 
Curdled  milk  has  long  entered  largely  into  the  diet  of  the  inhabit- 
ants of  many  countries  in  the  Near  East — e.g.,  Turkey,  Roumania, 

1  Fowler,  Med.  Press,  October  13,  1908. 

2  Mendel,  Milnch.  Med.  IVoch.,  1909,  Ivi.  433,  516. 

3  Vasoin,  Archiv /.  Verdaiiungs.  K.,  1905,  xi.  633  (abstract) 

*  See  also  Strauss,  Praktische  Winhe  fur  die  Chlorarone  Erndhmng.  Berlin  : 
S.  Karger,  1910. 

°  Peabody,  Med.  Record,  1907,  Ixxi.  381. 

8  For  further  details  see  Herschell,  '  Soured  Milk  and  Pure  Cultures  of  Lactic 
Acid  Bacilh  in  the  Treatment  of  Disease '  (Glaisher,  2nd  edition,  1909),  and 
•LacticAcid  Bacilli  Preparations'  (W.  Martindale,  lo,  New  Cavendish  Street,  W.) 


558  FOOD  AND  DIETETICS 

Bulgaria,  and  Serbia — the  best-known  preparation  being  the  Bulgarian 
yaghourt,  or  yohourth,  in  which  the  souring  is  brought  about  by  the 
Bacterium  Caucasicum,  or  Bulgarian  bacillus.  Metcbnikoff^  sug- 
gested the  use  of  this  preparation  in  the  treatment  of  disease,  and 
Cohendy^  first  proved  the  possibility  of  acclimatizing  the  Bulgarian 
bacillus  in  the  intestine,  and  of  lessening  intestinal  putrefaction  by 
so  doing.  The  Bulgarian  bacillus  has  the  advantage  over  other 
lactic-acid  producing  organisms  for  this  purpose,  in  that  it  is  both 
more  resistant  and  more  active. 

Since  its  introduction  this  method  of  treatment  has  attained  a 
wide  popularity,  and  soured  milk  is  now  largely  used,  either  in  a 
ready-made  or  home-made  form.  It  must  be  pointed  out,  however, 
that  many  commercial  preparations  of  soured  milk  either  do  not 
contain  the  Bulgarian  bacillus  at  all,  or  contain  it  in  a  very  impure 
form,  and  the  same  is  true  of  the  many  tablets  or  liquid  cultures 
which  are  sold  for  preparing  it  at  home,  and  which  are  designed  for 
the  direct  inoculation  of  the  intestine.^  That  some  of  the  impurities 
which  these  preparations  contain  may  produce  harmful  results  there 
can  be  no  doubt,  and  it  is  therefore  advisable  that  the  soured  milk 
should  always  be  prepared  at  home,  and  from  cultures  of  guaranteed 
purity. 

The  time  has  not  yet  come  for  a  final  pronouncement  on  the  value 
of  soured  milk  as  a  therapeutic  agent,  but  it  has  been  recommended 
in  cases  of  chronic  ill-health  without  obvious  cause,  in  neurasthenia 
and  intestinal  affections  —  e.g.,  colitis,  fermentative  diarrhoea,  con- 
stipation— besides  gout,  arterial  sclerosis,  and  some  skin  diseases. 
As  regards  many  of  these  affections  it  may  be  pointed  out  that  there 
is  little  or  no  proof  that  they  are  really  the  result  of  intestinal  putre- 
faction, and  any  improvement  which  soured  milk  may  produce  in 
them  is  probably  to  be  ascribed  to  the  fact  that  it  provides  an 
easfly-digested  form  of  food,  and  so  improves  the  patient's  nutrition.* 
On  the  whole  there  can  be  little  doubt  that  the  treatment  has 
been  much  overdone,  and  that  in  consequence  it  will  before  long  fall 
into  perhaps  unmerited  disrepute.  In  cases  of  hyperchlorhydiia  and 
chronic  acid  gastritis  it  is  always  contraindicated. 

i  'The  Prolongation  of  Life.' 

*  Comptes  Rendus  de  laSoc.  de  Biol.,  1906,  Ix.  558,  602,  872. 

*  See  report  of  a  discussion  on  'The  Lactic  Acid  Treatment,'  Froc.  Roy.  Soc.  oj 
Med.,  January,  19 10. 

*  See  Rosenberg,  Archiv  f.  Verduuungsk.,  1909,  xv.  458. 


[  559  ] 


CHAPTER  XXX 

ARTIFICIAL  AND  PREDIGESTED  FOODS  AND 
ARTIFICIAL  FEEDING 

In  this  chapter  we  shall  describe  some  patent  and  artificial  foods 
not  yet  dealt  with,  and  consider  the  methods  of  administering  food 
otherwise  than  by  the  mouth. 

I.  Artificial  Foods.* 

The  objects  of  artificial  foods  may  be  said  to  be  either  (i)  to 
present  a  maximum  of  nourishment  in  a  minimum  of  bulk,  or  (2)  to 
enable  one  easily  to  enrich  the  diet  in  respect  of  certain  of  its  chemical 
constituents. 

In  regard  to  the  former  of  these  objects,  it  is  well  to  reaUze  at  the 
outset  what  degree  of  concentration  of  food  is  chemically  possible. 
Let  us  take  first  the  case  of  the  proteins.  Lean  meat  may  be 
regarded  as  the  type  of  a  natural  protein  food.  It  contains  about 
one-fifth  of  its  weight  of  that  constituent,  the  rest  being  chiefly  made 
up  of  water.  If  one  drives  off  all  the  water  from  5  ounces  of  meat, 
there  will  be  left  behind  about  an  ounce  of  what  is  practically  pure 
protein.  Now,  this  may  be  regarded  as  the  maximum  degree  of 
concentration  of  which  protein  food  is  capable.  In  other  words,  an 
ounce  of  any  artificial  protein  food  can  never  represent  more  than 
5  ounces  of  lean  meat.  A  more  concentrated  protein  food  than  that 
is  a  chemical  impossibility.  One  can  realize  from  this  the  absurdity 
of  such  preparations  as  beef-lozenges.  Even  did  these  consist  of 
pure  protein  (which  they  never  do),  it  would  require  i  ounce  of 
them  at  least  to  be  equal  in  food  value  to  5  ounces  of  fresh  meat,  so 
that  the  amount  of  nutriment  contained  in  one  lozenge  must  be  very 
small  indeed. 

'  For  an  exhaustive  account  of  artificial  foods  see  '  Die  Kiinstlichen  Nahrpra- 
parate  und  Anregiingsmittel,"  by  Dr.  Max  Heim  (Berlin,  1901).  See  also  Julian 
Marcuse,  *  Kritische  Uebersicht  ueber  die  diatetischen  Nahrpraparate  dar 
Meuzeit/  Thtraf.  Mottdtsht/ic,  ifloo,  xiv.  257. 


56o  FOOD  AND  DIETETICS 

Or  take,  again,  the  case  of  the  casrbohydrates.  There  is  no  form 
of  carbohydrate  food  more  concentrated  than  sugar.  Any  fluid  or 
semi-fluid  carbohydrate  preparation  must  inevitably  be  of  lower 
nutritive  value  than  sugar,  for  it  contains  more  or  less  water,  tho 
food  value  of  which  is  nil.  Such  preparations  as  malt-extracts, 
therefore,  can  never  add  to  the  diet  as  much  carbohydrate  as  an 
equal  weight  of  ordinary  sugar. 

The  same  is  true  of  fats.  No  artificial  preparation  can  have  a 
higher  food  value  than  pure  olive-oil,  which  contains  no  water, 
or  dripping,  from  which  all  the  water  has  been  driven  off  by 
heat.  Even  ordinary  butter  contains  four-fifths  of  its  weight  of 
pure  fat. 

There  are,  then,  distinct  limits  beyond  which  the  concentration  of 
foods  cannot  be  carried,  and  the  idea  that  '  food  tabloids '  might  be 
prepared,  one  or  two  of  which  would  be  the  equivalent  of  an  ordinary 
meal,  is  seen  to  be  an  impossible  dream.  At  the  most,  all  that  the 
maker  of  concentrated  artificial  foods  can  hope  to  do  is  to  drive  off 
from  the  natural  food  the  excess  of  water  which  it  contains,  and 
even  then  most,  if  not  all,  of  the  original  water  must  be  returned  to 
the  food  before  it  can  be  eaten. 

It  may  be  questioned,  too,  whether  the  use  of  highly  concentrated 
foods  is  physiologically  defensible.  The  digestive  organs  are  not 
constructed  for  the  disposal  of  foods  in  an  extremely  compact 
form.  Such  forms  of  nutriment  make  large  demands  upon  the 
secretory  powers  of  the  stomach,  and  are  apt  to  be  irritating  to 
the  digestive  organs,  in  addition  to  which  the  total  absence  in 
them  of  '  ballast '  renders  them  unable  to  supply  an  adequate 
stimulus  to  the  peristaltic  movements  of  the  intestines.  As 
exclusive  foods,  therefore,  such  preparations  are  eminently  un- 
suitable. 

The  second  object  of  these  substances,  that  of  enabling  one  to 
enrich  the  diet  in  certain  ingredients,  is  more  legitimate.  Here  the 
artificial  food  is  used  simply  as  an  accessory  to  supplement  the  lack 
of  protein,  carbohydrate,  or  fat  in  other  articles  of  diet.  Their  small 
bulk  is  here  a  decided  advantage,  for  it  enables  them  to  be  added 
to  fluid  foods  without  appreciably  increasing  the  total  amount  of 
material  to  be  swallowed,  and  in  many  cases  of  illness  this  is  a 
desirable  thing  to  do. 

One  may  conclude,  then,  that  concentrated  foods  are  only  to  be 
used  as  accessories,  and  that  they  have  no  legitimate  place  in  the 
dietary  of  health. 


ARTIFICIAL  FOODS  561 

In  cases  of  sickness,  however,  they  have  a  definite  but  Hmited 
sphere  of  action.  In  these  circumstances,  when  appetite  is  in  abey- 
ance, it  is  often  a  question  not  so  much  of  getting  the  patient  to 
take  much  nourishment  as  of  persuading  him  to  eat  at  all.  It  is 
then  that  the  artificial  foods  serve  a  useful  purpose,  for  they  can  be 
varied  to  suit  the  caprices  of  the  patient,  and  though  the  amount  of 
actual  nourishment  which  they  yield  may  be  small,  they  may  yet 
kindle  a  desire  for  ordinary  foods.  The  value  of  any  artificial 
preparation  in  such  a  case  is  not  to  be  estimated  by  the  amount  of 
energy  it  yields,  so  much  as  by  its  aesthetic  qualities  and  the  degree 
to  which  it  pleases  the  patient.  Suggestion,  in  fact,  plays  a 
large  part  in  bringing  about  whatever  good  results  artificial  foods 
are  capable  of  producing. 


Artificial  Protein  Foods. 

I.  Undigested — (a)  Of  Animal  Origin. — Probably  the  best  of  the 
undigested  protein  foods  are  now  derived  from  casein,  the  chief 
protein  of  milk.  In  a  previous  chapter  (p.  143)  most  of  these 
have  been  described  (Plasmon,  Casumen,  Protene  flour,  etc.). 
They  have  the  advantage  of  being  colourless,  tasteless,  and  readily 
soluble,  so  that  they  can  easily  be  added  to  other  foods,  besides 
which  they  are  digested  without  difficulty  and  are  very  completely 
absorbed. 

Of  the  artificial  protein  foods  derived  from  meat,  most  belong 
to  the  predigested  class  to  be  considered  immediately.  Such  a 
preparation  of  dried  meat  as  pemmican,  however,  may  fairly  be 
regarded  as  belonging  to  this  group,  and  the  same  may  be  said 
of  the  dried  meat  prepared  by  the  Gye  and  other  processes  (see 
p.  165).  As  has  been  pointed  out  elsewhere  (p.  108),  anyone 
can,  with  a  little  trouble,  prepare  for  himself  a  powder  of  dried 
meat,  the  nutritive  value  of  which  is  as  high  as  that  of  any  artificial 
preparation. 

{b)  Of  Vegetable  Origin.  —  The  chief  vegetable  protein  foods  are 
Aleuronat,  Legnmin,  Kohorat,  Glidine,  and  Plantose.  The  first  is  a 
special  preparation  of  gluten  containing  80  to  90  per  cent,  of  protein. 
It  is  a  yellowish-brown  powder,  almost  insoluble  in  water,  and  can 
be  convenientlv  used  as  an  addition  to  semi  solid  foods.     It  is  largely 

36 


562  FOOD  AND  DIETETICS 

employed,  also,  in  the  feeding  of  diabetics,  and  has  the  advantage 
of  being  fairly  cheap. 

Legumin  (vegetable  casein)  is  the  chief  protein  of  pulses,  and  is 
a  valuable  and  highly  nutritive  substance,  apt,  however,  to  have  a 
rather  bitter  taste. 

Plantose  is  a  very  similar  vegetable  protein  obtained  from 
rape  seed.  Roborat  and  Glidine  have  been  described  already 
(p.  220), 

Tropon  is  a  protein  food  derived  both  from  animal  and  vegetable 
sources,  but  chiefly  from  fish  and  cheap  vegetables.  It  was  first 
prepared  by  Dr.  Finkler  of  Bonn.  It  is  a  brownish  powder,  free 
from  taste  and  insoluble  in  water,  but  can  be  easily  given  if  stirred 
up  in  thick  soups,  purees,  etc.  Three-quarters  of  an  ounce  of  it 
contain  as  much  protein  as  4  ounces  of  beef.  It  costs  4s.  per 
pound. 

2.  Digested  Protein  Foods,  or  'Peptone  Preparations.' — Before 
describing  the  members  of  this  group  in  detail,  one  or  two  pre- 
liminary questions  must  be  considered.  And  first  it  may  be  asked, 
Are  peptones  of  as  much  value  in  the  diet  as  proteins?  Are 
they  equally  well  assimilated  and  as  capable  of  repairing  tissue 
waste  ?  At  one  time  some  doubt  existed  about  these  questions,  but 
now  one  may  say  with  confidence  that  peptones  are  fully  capable  of 
playing  the  part  in  nutrition  ordinarily  taken  by  proteins,  provided 
they  be  given  by  the  mouth.*  If  injected  directly  into  the  circula- 
tion, it  is  true  that  they  are  not  assimilated,  but  if  taken  in  the 
ordinary  way  they  are  converted  into  natural  proteins  before  entering 
the  blood. 

It  has  also  been  objected  that  the  substitution  of  peptones  for 
ordinary  proteins  in  the  diet  must  tend  to  demoralize  the  stomach 
by  doing  some  of  its  work  for  it,  and  so  render  it  incapable,  through 
want  of  practice,  of  performing  its  usual  digestive  functions.  This 
objection  seems  to  be  a  hypothetical  rather  than  a  practical  one,  and 
with  the  exception  of  one  experiment  by  Roberts,^  on  which  he  did 
not  himself  lay  much  weight,  there  is  little  evidence  in  support  of  it. 
Further,  it  must  be  remembered  that  peptones  are  not  intended  for 
the  healthy,  but   for  those  in  whom   the  stomach  is  presumably 

^  See  especially  Hildebrandt,  Z«Y.  /.  Physiolog.  Chem..  1893,  xviii.  180;  Neu- 
meister,  Deut.  Med,  Woch^  1893,  xix.  866,  and  Von  Noorden,  Iherap.  Monatsheft^ 
1892,  vi.  271. 

^  'Digestion  and  Diet,'  p.  209. 


ARTIFICIAL   PROTEIN  FOODS  563 

already  incapable  of  doing  its  work,  and  in  such  a  case  the 
administration  of  peptones,  by  improving  general  nutrition,  might 
be  expected  to  strengthen  rather  than  to  enfeeble  the  digestive 
powers. 

A  much  more  real  disadvantage  attending  the  use  of  peptone 
preparations  is  their  tendency  to  produce  diarrhoea,  for  when  intro- 
duced suddenly  and  in  large  amounts  into  the  stomach  and  intestine, 
they  seem  to  induce  a  large  flow  of  water  into  the  alimentary  canal 
from  the  blood,  and  this  is  accompanied  by  an  mcreased  activity  of 
peristalsis.  For  this  reason  they  must  always  be  used  cautiously 
and  in  moderate  quantity,  while  in  conditions  of  diarrhoea  the  more 
concentrated  forms  should  be  avoided  altogether. 

It  may  be  questioned,  too,  whether  the  cases  in  which  peptones 
are  really  required  are  at  all  numerous,  for  an  inability  on  the  part 
of  the  stomach  to  digest  ordinary  proteins  properly  presented  to  it, 
and  in  a  state  of  fine  division,  must  be  regarded  as  of  very  rare 
occurrence.  On  the  other  hand,  peptone  preparations  appear  to 
have  the  power  of  exciting  a  secretion  of  gastric  juice,  and  of 
promoting  appetite  in  much  the  same  way  as  the  extractives  of 
meat.  Their  nutritive  value,  therefore,  is  indirect  rather  than  direct, 
and  is  to  be  measured  more  by  their  general  effect  upon  the  well- 
being  of  the  patient  than  by  the  amount  of  energy  which  they 
supply.^ 

Of   solid   peptone   preparations  Somatose^   is  the   best  example. 

Strictly  speaking,  it  consists  of  albumoses  rather  than  of  genuine 

peptone,  but  the  same  is  true  of  the  majority  of  the  so-called  peptone 

preparations,  and  for  dietetic  purposes  albumoses  and  peptones  may 

be  regarded  as  identical.      Somatose  is   prepared   from   meat,  and 

occurs  as  a  grayish  powder,  readily  soluble  in  water  and  practically 

devoid  of  taste  or  odour.     The  following  is  an  analysis  of  it  by 

Tankard:  8 

Water          14-25  per  cent. 

Alkali  albumin      ..         ..         ..21-83  ,, 

Coagulable  albumin         ..         ..  340  ,, 

Albumoses *..  3396  ,, 

Peptones     ..         *.         ..         ..  306  „ 

Meat  bases..         ..         ..         ..  262  „ 

Ash 530  „ 


*  See  a  paper  by  F.  Voit,  '  Ueber  den  Werth  der  Albumosen  und  Peptone  fiir 
die  Ernahrung  '  {Mi'inch.  Med.  Wochensch.,  1899,  xlvi.  172)  ;  also  M;ix  Voit,  Zeit. 
f.  Biologie,  1903,  xlv.,  N.F. ,  xxvii.  79. 

*  Supplied  by  the  Britis  i  Somatose  Co.,  165,  Queen  Victoria  Street,  E.C, 
^  A^leo's  '  Commercial  Organic  Analysis,'  iv,  384. 


564  FOOD  AND  DIETETICS 

Roughly  speaking,  it  may  be  said  to  contain  from  60  to  70  per 
cent,  of  building  material,  and  a  teaspoonful  of  it  is  equal  in  this 
respect  to  about  |  ounce  of  lean  meat.  It  can  be  easily  added  to 
fluid  or  semi-fluid  foods,  but  if  largely  used  may  produce  diarrhoea.* 
The  dose  recommended  is  about  three  or  four  teaspoonfuls  daily,  and 
it  seems  to  be  very  well  absorbed.*  Like  most  of  the  preparations 
we  are  now  considering,  Somatose  is  rather  expensive,  an  ounce  of  it 
costing  IS.  8d.,  and  yielding  for  that  sum  only  as  much  nutriment 
as  ^  pound  of  beef. 

Camrick's  Peptonoids  is  another  solid  preparation  containing 
predigested  proteins.     The  following  is  Tankard's  analysis  of  it :' 

Water          213  per  cent. 

Insoluble  proteins            ..         ..  1222  ,, 

Albumoses..          ..          ..         ..  3  17  „ 

Peptones     ..         ..          ..          ..  088  ,, 

Meat  bases            ..         ..         ..  287  „ 

Starch         ..         2364  „ 

Milk-sugar             4852  „ 

Fat 200  „ 

Ash 457 

It  will  be  observed  that  the  substance  owes  its  nutritive  value  to 
carbohydrates  rather  than  to  proteins,  and  that  the  larger  part  of  the 
latter  is  present  in  an  insoluble  form. 

The  tables  on  p.  565  contain  analyses  of  some  of  the  semi-solid 
and  liquid  peptone  preparations. 

'  See  Bernstein,  Btrlin.  Klin.  Woch.,  No.  8,  1S97. 

«  For  literature  relating  to  Somatose  and  its  uses,  see  Ilildebrandt,  Verhand. 
d.  \2ten  Cong.  /.  Inn.  Med.,  1S93,  395  :  ^'so  references  in  Edin.  Med.  Journ., 
February,  1899,  and  the  British  Physician,  July  15.  1899  ;  also  a  paper  by  Steven- 
son and  Luff,  Lancet.  September  30,  1899  The  conclusions  of  the  two  latter 
writers  are  as  follows  : 

i.  Somatose  is  a  true  meat  nutrient  possessing  restorative  and  stimulating 

powers. 
ii.  It  is  well  borne  by  delicate  patients. 

iii.  It  improves  digestion  and  causes  no  gastro-intestinal  disturbances, 
iv.  It  has  a  favourable  effect  on  general  metabolism. 
V.  It  never  gives  rise  to  the  appearance  of  albumin,  albumose,  or  peptone  in 

the  urine. 
•  Allen,  lac.  cit. 


COMPOSITION  OF  PEPTONE  PREPARATIONS      5^3 

COMPOSITION  OF  PEPTONE  PREPARATIONS  (CHIEFLY  FROM 
ANALYSES  BY  THE  AUTHOR). 


Preparation. 

Water. 

Soluble 

Proteins 

(chiefly 

Albumoses). 

Extractives  and 

other  Non  protein 
Organic  Matter. 

Mineral 
Matter. 

Koch's  Peptone       ..         ,. 

40- 16 

3478 

15-93 

689 

Liebig's  Peptone^    .. 

3i'9 

33-40 

246 

9-9 

Brand's  Beef  Peptone 

846 

70 

— 

1-4 

Denaeyer's  Peptone'^ 

7845 

I215 

4-32 

2-54 

Darby's  Fluid  Meat' 

2571 

30  60 

30  18 

13-50 

Armour's  Wine  of  Peptone 

83  0 

30 

12-9 

II 

Fairchild's  Panopepton     . . 

810 

30 

150 
(largely  sugar) 

xo 

Peptonized  Milk*    ••         ,, 

875 

176 

1004 

(  =  sugar,  fat, 

and  unaltered 

proteid) 

07 

'  Leyden's  '  Handbuch  der  Ernahrungstherapie.' 

'  Ihid.  ;  see  also  -Von  Noorden,  Theiap.  Monatsheft,  June,  1892. 

'  Horton  Smith,  Journ.  of  Physiolog.,  xii.  42,  1891,  and  Leyden's  'Handbuch. 

*  Horton  Smith,  loc.  cit. 


COMPOSITION   OF 

'   SOME   PEPTONE   PREPARATIONS   (KONIG). 

Preparation. 

Water. 

Total 
Nitro- 
gen. 

In- 
soluble 
Protein. 

Albu- 
moses. 

Pep- 

tones. 

Other 

Nitro- 
genous 
Com- 
pounds. 

Fat. 

Ash. 

Antweiler's 

Peptone 
Kemmerich's 

6  92 

12-85 

3-22 

14-54 

60- 15 

I  20 

0-54 

13-31 

Meat     Pep- 

tone (dry)   . . 
Koch's       Meat 

3330 

9-78 

I  10 

14-56 

3257 

9-97 

0-30 

7-73 

Peptone (dry) 
Darby's    Fluid 
Meat 

40- 16 
25-71 

780 
806 

I  42 

1595 

18-83 
30-60 

15-96 

0-79 

689 
13-50 

"Valentin  e's 

Meat-juice  . . 

59-07 

2-50 

— 

I-81 

487 

22-73 

— 

11-52 

Savory    and 

Moore's 

Fluid  Beef 
Benger's    Pep- 
tonized Beef 

2701 

8-77 

"*■ 

5-42 

2-74 

52-73 

■■" 

12-10 

Jelly 

89-68 

1-55 

— 

2-41 

4-75 

227 

— 

o-Sg 

Most  of  these  contain  so  much  water  that  their  nutritive  value  is  com- 
paratively small,  while  those  in  which  alcohol  is  present  are  open  to 
the  same  objections  as  other  dietetic  or  medicinal  wines ^  (see  p.  388). 

^  Analyses  by  Harrington  {Boston  Med.  and  Surg.  Journ.,  1902,  clxviii.  283)  have 
shown  for  example  that  'liquid  pepfonoids'  contain  23  per  cent,  of  alcohol  by 
volume,  and  that  the  maximum  dose  for  an  adult  per  day  -would  yield  as  much 
intoxicant  as  is  contained  in  3^  ounces  of  whisky.  'Panopepton  '  contains  i8"95 
per  cent,  of  alcohol  by  volume. 


566 


FOOD  AND  DIETETICS 


Home-made  peptonized  foods,  prepared  by  aid  of  such  agents  as 
liquor  pancreaticus  or  '  zymine,'  are  now  so  well  known  and  widely 
employed  that  a  special  description  of  them  is  unnecessary.^ 
Peptonized  milk  is  that  most  commonly  used.  An  analysis  of  it 
will  be  found  in  the  foregoing  table.  Condensed  peptonized  milk  is 
sold  in  tins  by  Messrs.  Savory  and  Moore. 

Gruels  of  various  sorts  can  be  prepared  in  a  similar  way, 
peptonized  milk  gruel  being  one  of  the  best.  Such  home-made 
preparations  are  mostly  to  be  preferred  to  commercial  articles,  and 
have  also  the  advantage  of  being  very  much  cheaper. 


Artificial  Carbohydrate  Foods. 

Many  patent  foods  which  might  justly  be  included  in  this  section 
have  been  already  dealt  with  under  the  cereals,  pulses,  etc.  The  only 
group  which  remains  to  be  considered  is  that  of  the  malt-extracts. 
These  are  prepared  by  evaporating  down  an  infusion  of  malted 
barley  at  low  temperatures  or  in  vacuo.  The  object  of  evaporating 
them  in  that  way  is  to  preserve  in  an  active  form  the  diastasic 
ferment  present  in  the  malt ;  and  the  special  apparatus  required  for 
this  purpose  is  one  cause  of  the  expense  of  such  preparations. 

The  following  table  contains  the  results  of  the  analyses  of  some 
standard  malt-extracts  r^ 

COMPOSITION  OF  MALT-EXTRACTS. 


Total 
Solids. 

Reducing 
Sugars.* 

Protein. 

Dex- 
trin. 

Ash. 

Alcohol. 

Diastasic 
Power. 

Kepler  Extract  of  Malt    . . 

784 

677 

566 

7"4 

15 

— 

380 

Trommer's  Extract  of  Malt 

736 

559 

405 

«-3 

II 

— 

23 

Allen   and    Hanbury's  Ex- 

tract of  Malt 

700 

652 

4-55 

13-4 

1-2 

— 

39 

D.C.L.  Malt-Extract 

78-3 

709 

625 

100 

14 

— 

366 

Cream  of  Malt        ..         .. 

73« 

608 

555 

i3» 

I-« 

— 

86 

Maltine         

673 

61-9 

5'25 

5"o 

12 

— 

940 

Standard  Malt-Extract     .. 

766 

70*0 

53 

122 

14 

— 

382 

Bynin 

529 

51-6 

33 

31 

0-9 

«-3 

38 

Standard  Liquid  Malt-Ex- 

tract 

537 

516 

55 

23 

i-i 

5'o 

866 

Hoff's  Malt-Extract 

7S 

25 

04 

23 

02 

3'i 

0 

The  average  composition  of  these  substances  given  by  Klemperer* 
is  as  follows : 

. .     5  to  6  per  cent. 


Sugar     . . 
Soluble  starch. 


50  to  55  per  cent. 
10  ,,  15 


Proteins 
Ash.. 


1  For  details,  see  Roberts'  '  Digestion  and  Diet,'  2nd  edit.,  p.  192.  Full  direc- 
tions for  preparing  peptonized  foods  are  supplied  along  with  the  agents  mentioned 
in  the  text. 

2  Brit.  Med.  Journ.,  1909,  ii.  1477.  ^  Calculated  as  maltose. 
*  Leyden's  '  Handbuch  der  Ernahrungstherapie." 


A 


MALT  EXTRACTS  567 

A  large  dessertspoonful  of  such  an  extract  weighs  about  20  grms. 
and  has  a  fuel  value  of  60  Calories,  or  about  as  much  as  an  egg. 

In  the  above  analyses  the  whole  of  the  nitrogenous  matter  has 
been  counted  as  protein,  but  it  is  very  doubtful  if  that  is  quite  accurate. 
Some  of  the  nitrogen  is  almost  certainly  present  in  other  forms. 

Desiccated  malt  extracts  ^  from  which  all  the  water  has  been 
removed  are  also  prepared.  They  are  of  high  nutritive  value  and 
active  diastasic  power,  and  are  in  many  respects  more  convenient 
than  the  ordinary  extracts.  Hoff's  Malt  Extract,  on  the  other  hand, 
is  a  liquid  preparation.  Maltova  is  a  combination  of  malt-extract 
and  eggs. 

Malt-extracts  may  be  prescribed  with  one  of  two  objects  :  (i)  To 
enrich  the  supply  of  carbohydrates  in  the  diet ;  (2)  to  aid  the  digestion 
of  starchy  foods  by  means  of  the  diastase  which  the  extract  contains. 
The  advantages  possessed  by  malt-extracts  for  accomplishing  the 
former  of  these  objects  are  not  quite  apparent.  Treacle  and  golden 
syrup  both  contain  a  considerably  higher  percentage  of  sugar,  and 
are  vastly  cheaper.  It  is  true  that  malt-sugar  is  less  apt  to  irritate 
the  stomach  than  the  cane-sugar  which  treacle  and  syrup  contain ; 
and  although  not  capable  of  direct  absorption  as  such,  maltose  may 
yet  be  regarded  as  a  partially  digested  form  of  carbohydrate.  But 
in  both  these  respects  we  have  in  ordinary  honey  a  superior  food. 

Honey  has  the  following  composition : 

Water  16  to  13  per  cent. 

Invert  sugar  ..         ..         ..  78  ,,  74        ,, 

Cane-sugar  ..  ..  ..         2  "69  „ 

Proteid        I'zg  ,, 

x\sb 0-12  ,, 

That  is  to  say,  it  is  actually  richer  in  sugar  than  malt-extract ;  and 
a  dessertspoonful  has  a  fuel  value  of  75  instead  of  60  Calories. 
Furthermore,  the  sugar  of  honey  is  really  in  a  predigested  form, 
and  ready  for  immediate  assimilation.  As  a  source  of  carbohydrate, 
therefore,  honey  is  in  every  way  preferable  to  malt-extracts,  besides 
being  a  good  deal  cheaper; 2  and  it  may  be  used  with  great  advantage 
in  every  case  in  which  one  wishes  to  supplement  the  supply  of  carbo- 
hydrates in  the  diet. 

The  second  property  of  malt-extracts — that  of  acting  upon  starch 
by  means  of  the  diastase  which  they  contain — is  but  rarely  present 

^  E.g.,  Curtis'  Desiccated  Malt-Extract  (Curtis  and  Co.,  48,  Baker  Street,  W.)  ; 
'Gramah'  (Thomas  Christy  and  Co.,  Old  Swan  Lane,  Upper  Thames  Street, 
E.C.),  and  Dr.  Wander's  Dry  (Crystalline)  Extract  of  Malt.  For  results  obtained 
from  the  use  of  desiccated  malt-extract  see  '  Powdered  Malt-Extract  as  a 
Nutrient,'  by  Dr.  Kingston  Fox  (Brit.  Med.  Journ.,  1902,  i.  £35). 

'  Malt-extracts  cost  about  3s.  the  pound,  honey  costs  about  gd. 


568  FOOD  AND  DIETETICS 

to  the  mind  of  the  prescriber.  The  cases  in  which  such  an  action  is 
desired  are  not,  indeed,  at  all  numerous,  and  are  practically  confined 
to  the  group  of  so-called  amylaceous  dyspepsias.  Even  in  such  a 
case  malt-extract  is  not  the  best  preparation  to  employ.  No  matter 
how  carefully  the  extract  may  be  prepared,  it  always  seems  to  lose 
something  of  its  diastasic  power  in  the  process  (Roberts) ;  and  it  is 
far  more  certain,  as  well  as  cheaper,  and  one  may  add  pleasanter, 
to  make  an  infusion  of  malt  at  home,  and  either  use  it  as  a  beverage 
at  meals,  or,  preferably,  stir  it  into  starchy  foods,  such  as  puddings 
or  gruel,  before  they  are  eaten. ^ 

The  value  of  milk-sugar  as  a  means  of  supplementing  the  carbo- 
hydrates of  the  diet  must  not  be  forgotten.  Its  comparative  freedom 
from  sweetness  makes  it  specially  suitable  for  such  a  purpose.  If 
^  ounce  of  it  is  dissolved  in  5  or  6  ounces  of  milk,  the  nutritive  value 
of  the  latter  is  increased  by  nearly  60  Calories.  This  may  often  be 
taken  advantage  of  in  feeding  patients  with  acute  fevers. 

Artificial  Fatty  Foods. 

In  most  cases  these  consist  of  some  kind  of  fat  presented  in  the 
form  of  an  emulsion,  cod-liver  oil  being  the  special  variety  of  fat 
usually  employed. 

The  object  of  emulsification  is  to  render  the  fat  more  palatable, 
and  also  to  aid  its  digestion.  The  former  object  is  undoubtedly 
attained;  the  achievement  of  the  latter  is  not  so  certain.  It  must  be 
remembered  that  what  is  now  known  of  the  digestion  and  absorption 
of  fat  makes  it  certain  that  the  process  is  mainly  a  chemical  one, 
and  not  a  mere  physical  absorption  of  the  fat  in  the  form  of  fine 
particles.  Hence,  though  emulsification  may  be  a  useful  preliminary 
to  digestion,  fat  so  presented  cannot  be  regarded  as  ready  for 
immediate  reception  into  the  blood.  Like  the  malt-extracts,  there- 
fore, fat  emulsions  are  only  partially  predigested  foods. 

The  emulsifying  agent  in  these  preparations  is  either  an  alkaline 
solution,  mucilage,  glycerine,  or  malt-extract.  Of  these,  the  three 
last  are  to  be  preferred,  for  they  are  unaffected  by  the  acidity  of  the 
gastric  juice,  which  is  apt  to  destroy  an  alkaline  emulsion. 

An  ordinary  cod-liver  oil  emulsion  contains  about  half  its  weiglit 
of  fat,  and  has  a  fuel  value  about  double  that  of  an  equal  quantity  of 
malt-extract.     The  question  whether  cod-liver  oil  has  any  specific 

'  Roberts  recommends  an  infusion  made  by  soaking  3  piled  tablespoonfuls  of 
crushed  malt  in  ^  pint  of  cold  water  overnight,  and  straining  through  muslin 
till  clear.  It  may  be  preserved  in  a  tightly-corked  bottle  with  the  addition  of  a 
few  drops  of  chloroform  ('  Digestion  and  Diet,'  p.  230,  where  detailed  directions 
for  the  use  of  such  an  infusion  are  given) 


FAT  EMULSIONS 


569 


virtues  other  than  those  of  an  easily-digested  fat  cannot  be  discussed 
here  ;  but  in  the  case  of  the  purified  oils,  at  any  rate,  any  such  specific 
qualities  can  hardly  be  present,  unless  they  be  due  to  cholesterol,  the 
food  value  of  which,  however,  is  very  questionable. 

A  preparation  called  Lipanin  has  been  largely  used  in  Germany 
as  a  substitute  for  cod-liver  oil.  It  consists  of  ordinary  olive  oil 
containing  6  per  cent,  of  oleic  acid.  The  presence  of  the  latter  is 
supposed  to  facilitate  emulsification  and  absorption  in  the  intestine ; 
but  experiment  has  not  shown  that  Lipanin  is  better  absorbed  than 
ordinary  forms  of  fat.i  The  composition  of  some  standard  emul- 
sions of  cod-liver  oil  and  malt  is  as  follows :' 


Preparation. 

Protein. 

Reducing  Sugars 
calculated  as  Maltose. 

Fat. 

Diastatic 
Power. 

Bynol 

Trommer's  Oil  and  Malt 

•  Maltine '  and  Cod-Liver  Oil . . 

Kepler's  Oil  and  Malt  . . 

•Diamalt '  with  Ccd-Liver  Oil 

4-6 
2-4 
3-8 
3  4 
5-1 

52-2 
41-4 
41-4 
42-5 

51-0 

12 '9 

29-9 

227 

17-4 

i6-6 

22 

35 
284 

3 

592 

Miol  is  a  combination  of  emulsified  olive  oil  with  malt-extract,  and 
contains,  in  addition,  iodine,  phosphorus,  and  other  ingredients.  It 
is  designed  to  replace  cod-liver  oil,  and  contains  22  per  cent,  of  fat 
and  41  per  cent,  of  reducing  sugar. 

Virol  is  another  cod-liver  oil  substitute.  It  is  prepared  from  bone 
marrow,  the  yolk  of  eggs,  and  malt-extract  flavoured  with  lemon - 
juice,  and  has  approximately  the  following  composition  : 


Water 
Fat . . 
Carbohydrates 


21*1  per  cent. 
12-3         ,, 
59'o 


Protein 
Ash.. 


2*8  per  cent. 
1-6 


It  is  an  agreeable  preparation  of  very  considerable  nutritive  value. 

Cremalto  is  a  combination  of  Devonshire  cream  and  malt  which 
has  the  following  composition  :^ 


Water 
Fat . . 
Carbohydrates 


267  per  cent. 

"7 

56-3 


Proteia 
Ash.. 


4'i  per  cent. 
13 


It  also  is  a  pleasant  and  nourishing  preparation. 

Pancreatic  Emulsion  is  another  substitute  for  cod-liver  oil.  It  is 
made  by  pounding  up  lard  with  pig's  pancreas,  with  the  addition  of 
water,  straining,  and  exhausting  the  strained  substance  with  ether. 
The  ether  is  distilled  off,  and  the  residue  of  fat  is  mixed  with  rectified 

*  See  Leyden's  'Handbuch  der  ErnahruDgstherapie,'  p.  302. 

*  Brit.  Med.  Journ.,  January  i,  1910. 

*  Analysis  in  Brit.  Med.  Journ.,  1910,  i.  29. 


570  FOOD  AND  DIETETICS 

spirit  and  water,  and  emulsified  by  agitation.    Oil  of  cloves  is  added 
to  give  flavour  and  aid  preservation. 

It  is  not  difficult  to  take,  but  is  no  richer  in  fat  than  ordinary 
butter,  and  considerably  more  expensive. 

Spermaceti  used  'to  be  largely  employed  as  a  means  of  giving  fat, 
but  has  now  dropped  out  of  use.  It  was  given  in  the  form  of  a 
powder  mixed  with  sugar,  and  |  ounce  could  be  taken  daily. ^  It  is 
well  borne  and  not  difficult  to  absorb. 

The  objection  to  all  these  artificial  preparations  is  their  expense, 
and  for  that  reason,  if  for  none  other,  the  use  of  natural  fats  is 
preferable.2  Of  these,  cream  and  butter  are  the  most  suitable,  for 
there  are  but  few  persons  who  are  unable  to  digest  milk-fat. 
Ordinary  cream,  obtained  by  skimming,  contains  about  20  per  cent, 
of  fat,  and  three  spoonfuls  of  it  are  more  than  equal  in  fuel  value  to 
one  spoonful  of  cod-liver  oil  emulsion.  Butter  has  80  per  cent,  of 
fat,  and  can  be  taken  in  large  quantities  if  well  mixed  with  starchy 
foods  such  as  mashed  potato.  Almonds  are  also  a  rich  source  of  fa,t, 
of  which  they  contain  more  than  half  their  weight.  Chocolate,  too, 
has  20  per  cent,  of  fat  and  50  per  cent,  of  sugar  in  addition. 
Lastly,  one  should  not  forget  the  value  of  toffee  as  a  concentrated 
form  of  fat  and  carbohydrate  in  about  equal  proportion.  It  has  the 
further  advantage  that  much  of  the  sugar  which  it  contains  is  in  the 
easily  digested  '  invert  *  form.  It  may  be  specially  recommended  in 
the  case  of  children  who  are  unable  to  take  cod-liver  oil  or  other 
forms  of  fat,  and  if  given  only  at  the  end  of  meals  is  not  likely  to  do 
any  harm.  If  the  merits  of  some  of  these  natural  forms  of  fat  were 
rightly  appreciated,  there  would  be  but  little  need  to  have  recourse 
to  artificial  preparations. 

2.  Artificial  Feeding.' 

Rectal  Feeding  and  Nutrient  Enemata. 

Rectal  feeding  has  constituted  a  therapeutic  resource  ever  since 
medical  science  existed,*  but  it  is  only  within  recent  times  that  the 
value  of  this  method  of  administering  nourishment  has  been  sub- 
jected to  careful  scientific  scrutiny. 

1  See  Senator,  Berlin.  Klin.  Woch.,  1887,  xxiv.  213. 

•  I  have  recently  used  an  emulsioi,  of  cotton-seed  oil  prepared  with  the  addition 
of  6  per  cent,  of  oleic  acid  as  a  substitute  for  cod-liver  oil  with  quite  satisfactory 
results.  Pilchard  oil  may  be  used  in  a  similar  way.  Both  of  these  have  the 
advantage  of  being  much  cheaper  than  cod-liver  oil. 

2  For  a  critical  review  of  the  whole  subject  of  artificial  feeding,  see  an  article 
entitled  '  Extrabuccal  Feeding,'  by  C.  A.  Ewald,  Med.  Record,  1900,  Iviii.  241. 

*  For  a  sketch  of  the  history  of  the  subject,  see  the  valuable  monograph  by 
Dr.  A.  P.  Gros,  '  Traitement  de  certaices  Maladies  de  TEstomac  par  la  Cure  de 
Repos  absolu,'  etc ;  Paris,  i8g8. 


RECTAL  FEEDING  571 

The  absorptive  power  of  the  large  intestine  for  proteins  was  first 
investigated  by  Eichhorst,^  Leube,^  Brandenburg,^  Huber,*  Ewald,^ 
Plantenga,^  and  others.  Their  results  showed  t  )at :  (i)  Peptone  is 
well  absorbed ;  (2)  eggs  given  alone  are  not  well  absorbed,  but  if 
15  grains  of  salt  are  added  to  each  egg  they  are  almost  as  well 
utilized  as  if  they  had  been  peptonized ;  (3)  raw-beef  juice  is  very 
completely  absorbed ;  (4)  albuminoids  such  as  gelatin  are  not 
absorbed. 

Results  obtained  with  enemata  of  casein  were  conflicting.  Some 
of  the  above  observers  state  that  it  is  not  well  absorbed,  but 
Eichhorst,  and  more  recently  Ehrstrom'  (who  used  a  soluble  casein 
preparation)  maintain  that  it  is  well  taken  up  by  the  rectal  mucous 
membrane.  Hoppe®  also  found  that  Sanatogen  is  absorbed  to  the 
extent  of  fully  77  per  cent.,  and  Goliner^  that  Plasraon  dissolved  in 
hot  water  makes  a  satisfactory  enema. 

Later  observations  tend  to  throw  much  doubt  upon  the  trust- 
worthiness of  these  earlier  experiments  upon  the  absorption  of 
proteins  from  nutrient  enemata.  Rendle  Short  and  By  waters,  *°  for 
instance,  who  have  reinvestigated  the  whole  subject,  come  to  these 
conclusions : 

1 .  The  older  observations  on  the  absorption  of  foodstuffs  from  rectal 
enemata,  based  on  the  analysis  of  rectal  'wash-outs,'  are  unreliable. 

2.  The  daily  output  of  nitrogen  in  the  urine  of  patients  given 
nutrient  enemata  of  milk  or  eggs  peptonized  for  twenty  or  thirty 
minutes  demonstrates  that  almost  no  nitrogenous  matter  is  absorbed. 

3.  Modern  physiological  opinion  holds  that  proteins  are  absorbed 
principally  as  amino-acids.  The  failure  of  the  rectum  to  absorb 
ordinary  nutrient  enemata  is  largely  due  to  the  fact  that  peptones 
are  given  instead  of  amino-acids. 

4.  Chemically  prepared  amino-acids,  or  milk  pancreatized  for 
twenty-four  hours  so  that  amino-acids  are  separated,  allows  of  a 
much  better  absorption  of  nitrogenous  foodstuffs  from  the  rectum, 
as  demonstrated  in  five  cases  by  the  high  nitrogen  output  in  the  urine. 

1  Archiv.  f.  Physiolog..  107 1,  iv.  570. 

'  Leyden's  '  Handbuch  der  Ernahrungstherapie,'  p.  496  et  seq. 

*  Deut.  Archiv.  f.  Klin.  Med.,  1896,  Iviii.  71. 

*  Ibid.,  1891,  xlvii.  495. 

*  Archiv./.  Anat.  und  Physiolog.,  1S99,  Supp.  Bd.,  p.  160. 

*  Centralbl.  f.  Physiolog.,  1899,  xii.  734,  (abstract  of  dissertation) ;  see  also  Gros, 
op.  cit. 

'  '  Ueber  den  Nahrwerth  der  Casein  Klystiere, '  Zeit.  f.  Klin.  Med.,  1903,  xlix. 

377- 

*  Miinch.  Med.  Wochensch.,  1904,  li.  2294. 

'  Zeit.  f,  Phys.  und  Didt.  Therapie,  February,  1907. 
w  •  Amino-Acids  and  Sugars  in  Rectal  Feeding,'  Brit.  Med.  Journ,,  1913,  i.  1361 


572  FOOD  AND  DIETETICS 

5.  The  low  output  of  ammonia  nitrogen  shows  that  this  high 
output  was  not  due  to  the  absorption  of  putrefactive  bodies.  Th© 
rectal  washings  were  not  offensive. 

As  regards  carbohydrates,  it  has  been  found  that  sugars  are  well 
absorbed,  but  are  apt  in  concentrated  solution  to  prove  irritating  to 
the  mucous  membrane.  Leube  advises  that  the  solution  should  not 
be  stronger  than  10  to  20  per  cent.,  and  that  not  more  than  300  c.c. 
should  be  given  at  one  time.  Even  then  there  is  a  risk  of  the 
enema  being  very  soon  returned.  A  6  per  cent,  solution  of  dextrose 
in  tap-water,  which  is  isotonic  with  blood,  is  much  less  irritating.^ 
Curiously  enough,  starch  seems  to  be  fairly  well  absorbed,^  even 
when  given  in  the  raw  state :  50  to  100  grammes  of  it  may  be  given 
in  300  c.c.  of  water.     It  is  not  at  all  irritating. 

Fats  are  not  at  all  well  absorbed  when  given  by  the  bowel.'  The 
total  amount  absorbed  depends  on :  (i)  The  absolute  quantity  ad- 
ministered ;  (2)  its  length  of  stay  in  the  bowel ;  (3)  the  temperature 
of  the  enema  and  the  presence  or  absence  in  it  of  common  salt.  Not 
more  than  25  grammes  of  fat  should  be  given  at  once,  and  with 
at  least  as  much  water.  The  enema  should  be  given  at  the  body 
temperature,  and  enough  salt  added  to  form  a  normal  saline  solu- 
tion. The  bowel  should  be  empty,  and  only  one  enema  given  daily. 
Even  under  these  favourable  conditions,  not  more  than  10  grammes 
of  fat  are  likely  to  be  absorbed  daily.  Scarcely  any  of  the  fat  of 
ordinary  milk  enemata  appears  to  be  retained. 

It  follows  from  these  experimental  results  that  the  best  ingredients 
for  nutrient  enemata  are:  (i)  Peptones,  albumoses,  and  powdered 
casein  preparations ;  (2)  eggs,  with  the  addition  of  salt ;  (3)  raw- 
beef  juice ;  (4)  dilute  solutions  of  grape-sugar  or  dextrin ;  (5)  and 
perhaps  unboiled  starch.  To  this  list  should  be  added  alcohol, 
which  is  perhaps  better  absorbed  by  the  large  intestine  than  any- 
thing else  except  water.* 

1  Mutch  and  Ryffel,  Brit.  Med.Journ.,  1913,  i.  in. 

2  This  statement  is  not  quite  borne  out  by  the  observations  of  Reach 
('Ueber  Resorption  von  Kohlehydraten  von  der  Schleimhaut  des  Rektums,' 
Zeit.  /.  Dial,  und  Pkysik.  Therapie,  1903,  vii.  229).  He  administered  enemata  of 
60  grammes  of  sugar  or  dextrin  in  120  to  200  c.c.  of  water,  and  of  100  grammes 
of  starch  in  300  c.c.  of  water,  using  the  respiratory  quotient  as  the  test  of  absorp- 
tion. He  concludes  that  some  sugar  is  absorbed,  but  very  little  starch.  He  is 
inclined  to  recommend  the  use  of  dextrin,  for  it  is  as  well  absorbed  as  sugar, 
and  less  irritating  to  the  mucous  membrane.  O.  Griinbaum  has  found  that 
30  grammes  of  sugar  can  be  absorbed  without  the  production  of  glycosuria. 

3  See  Deucher,  Deut.  Archiv.  /.  Klin.  Med.,  1897,  Iviii.  210. 

*  The  whole  subject  of  rectal  alimentation  was  reviewed  by  Sharkey  in  the 
Bradshaw  Lecture,  1906  (Lancet,  1906,  ii.  1263),  but  his  conclusions  are  in  the 
main  in  agreement  with  those  expressed  in  the  above  paragraph.  He  gives  a 
very  complete  bibliography  of  the  subject. 


NUTRIENT  EN  EM  AT  A  573 

It  may  be  admitted  that  the  capacity  of  the  large  intestine  io 
absorb  some  of  these  articles  is  not  easy  of  explanation.  It  is  pretty 
clearly  established  that  the  colon  secretes  no  digestive  ferments. 
How,  then,  it  may  be  asked,  is  it  capable  of  absorbing  such  sub- 
stances as  egg-white  and  unboiled  starch  ?  There  is  one  easy  way 
out  of  the  difficulty,  and  that  is  by  assuming  the  occurrence  of  a 
reverse  peristalsis,  which  carries  substances  injected  into  the  rectum 
up  above  the  ileo-caecal  valve  into  the  small  intestine.  That  such  a 
reverse  peristalsis  is  possible  is,  I  think,  no  longer  open  to  doubt. 
It  is  proved  by  the  experiments  of  Griitzner,*  by  the  observations  of 
Nencki,  Macfadyen  and  Sieber  on  a  patient  with  a  fistula  at  the 
lower  end  of  the  ileum,^  and  by  the  incontestable  fact  of  the  occa- 
sional vomiting  of  enemata  by  hysterical  patients.^ 

It  is  very  probable  that  in  this  way  a  part  at  least  of  a  nutrient 
enema  gets  carried  into  the  small  intestine,  where  absorption  can 
readily  occur.  Variations  in  the  patency  of  the  ileo-caecal  valve  may 
explain  the  different  degrees  to  which  different  individuals  absorb 
such  enemata. 

Special  emphasis  must  be  given  to  the  great  extent  to  which  the 
addition  of  salt  to  nutrient  enemata  promotes  their  absorption. 
This  is  a  practical  matter  of  the  first  importance.  Its  modus  operandi, 
however,  is  not  easy  of  explanation.  It  may  perhaps  stimulate  the 
appearance  of  the  reverse  peristalsis  above  referred  to,  or  it  may 
excite  the  intestinal  cells  to  greater  absorptive  efforts,  while  it 
undoubtedly  facilitates  the  diffusion  of  the  enema  over  the  surface 
of  the  bowel. 

Putting  aside  these  rather  academical  discussions,  there  is 
abundant  clinical  evidence  for  the  feasibility  of  nourishing  patients, 
for  some  time  at  least,  by  the  rectum  exclusively.  In  several  cases 
cited  by  Gros,  patients  were  fed  by  this  method  alone  for  as  long  a 
period  as  three  weeks,  and  with  but  little  loss  of  weight* 

The  process,  however,  cannot  be  continued  indefinitely,  for,  apart 
altogether  from  the  fact  that  the  rectum  sooner  or  later  becomes 
intolerant,  one  can  hardly  hope,  allowing  for  deficient  absorption, 
to  get  more  than  500  Calories  of  energy  into  the  blood  daily  by  this 
means,  and  that  is  only  about  a  quarter  or  at  most  one-third  of  the 
amount  required  even  by  patients  who  are  kept  very  warm  and  at 
absolute  rest.     Much  of  the  value  of  nutrient  enemata,  indeed,  is 

1  Pfluger's  Archiv.,  1898,  Ixxi.  492. 

2  Archiv. /.  Exper.  Path,  unci  Pharmak.,  1891,  xxviii.  311. 

3  Gros,  op.  cit.,  chap.  iv. 

*  See  also  Ewald,  Archiv.  f.  An^t.  und  Physiolog.,  1899,  Supp,  Bd.,  160,  and 
Rest,  Berlin.  t\Un,  Woch.,  1899,  xxxvi.  660,  666. 


574-  FOOD  AND  DIETETICS 

almost  certainly  due  to  absorption  of  water,  which  may  explain  the 
cases  in  which  weight  is  gained.  It  is  only  in  exceptional  cases  that 
one  can  prevent  tissue-loss  by  their  use,  and  the  best  that  can  be 
hoped  for  is  to  prevent  the  patient  losing  ground  when  already  in 
a  condition  of  decided  sub-nutrition.'  It  has  been  proved,  also,  that 
the  administration  of  a  nutritive  enema  is  followed  by  the  out- 
pouring of  some  gastric  juice  into  the  stomach,  and  in  cases  of 
gastric  ulcer  this  may  be  harmful  and  interfere  with  healing. 

Milk  is  most  commonly  used  as  the  basis  for  enemata,  as  it  is 
simple,  convenient  and  unirritating,  in  spite  of  the  fact  that  only 
about  one-third  of  the  casein  which  it  contains  is  absorbed.  The 
following  are  some  of  the  formulae  for  enemata  containing  milk 
recommended  by  Leube:^ 

Peptone  and  Milk  Encmm 
Peptone,  60  grammes. 
Milk,  250  c.c. 

Egg  and  Milk  Enema, 
3  eggs. 

3  grammes  of  common  salt. 
Milk,  250  c.c. 

Sugar  and  Mtlk  Eiuma. 
Grape-sugar,  60  grammes.-* 
Milk,  250  c.c. 

Starch  and  Milk  Enema. 
Starch  (unboiled*),  60  to  70  grammes. 
Milk,  270  C.C. 

It  might  be  well  to  peptonize  the  milk  first.  Somatose  may  be 
used  instead  of  peptone. 

Red  wine  is  recommended  as  an  addition  by  many  Continental 
writers.  The  alcohol  which  it  contains  is  readily  absorbed,  while 
its  astringency  and  slight  acidity  seem  to  favour  retention  of  the 
enema.*  The  following  formulae  are  examples  : 
tered  by  means  of  an  ordinary  enema  or  pressure  syringe.  The 
enema  should  be  given  slowly,  and  the  patient  should  lie  quiet  foi 
an  hour  after  it  has  been  injected.  Three  or  four  enemata  in  the 
twenty-four  hours  is  a  sufficient  quantity,  and  oke  cleansing  injection 
should  be  given  daily,  for  absorption  is  greatly  promoted  by  having 
the  surface  of  the  mucous  membrane  clean.  If  the  enema  is  badly 
retained,  a  little  opium  may  be  added. 

Nutrient  suppositories  cannot  be  recommended.  They  usually 
contain  peptone,  but  at   most  not  more  than  125  grains  in  each, 

*  See  Boyd  and  Robertson,  loc.  cit. 

2  Brit.  Med.  Journ.,  igoo,  ii.  424,  and  1901,  xi.  788. 

^  Supplied  by  Parke,  Davis  and  Co.  *  Loc.  cit. 

6  '  Rectal  Alimentation,'  Boston  Med.  and  Surg.  Journ.,  January,  1914,  p.  41. 

*  Loc.  cit. 


NUTRIENT  ENEMATA  575 

Boas'  Enema, 

Milk,  g  oz. 

Yolks  of  2  eggs. 

A  pinch  of  salt. 

Red  wine,  ^  oz. 

Starch  or  arrowroot,  ^  oz. 

Riegel's  Enem», 

Milk,  9  oz. 

2  to  3  eggs. 

2  to  3  pinches  of  salt. 

Red  wine,  i  oz. 

Tournitr's  Enema. 

Beef-tea,*  5  ozs 
The  yolks  of  6  eggs. 
2  small  spoonfuls  of  salt. 
Red  wine,  i  oz. 

The  eggs  should  be  beaten  up  for  at  least  five  minutes,  so  as  to 
mix  them  thoroughly. 

Boyd  and  Robertson*  find  that  for  practical  purposes  the  following 
is  the  best  formula  to  use : 

The  yolks  of  two  sggs 
30  grammes  pure  dextrose. 
o"5  gramme  common  salt. 
Pancreatized  milk  to  300  c.c 

Given  every  six  hours  the  amount  of  nourishment  injected  would 
equal  1,200  Calories.  Absorption  under  favourable  circumstances 
might  amount  to  500  Calories,  but  would  probably  be  much  less. 

Leube's  Pancreas  Enema  is  an  attempt  to  imitate  natural  intestinal 
digestion.  It  consists  of  a  mixture  of  chopped  pancreas  and  lean 
meat,  with  the  addition  of  some  fat,  in  the  following  proportions : 

Pancreas 50  to  100  grammes. 

Meat  ..         ..         ..         ..     150  ,,  300        ,, 

Fat 30  .,     45 

The  pancreas  and  meat  should  both  be  free  from  fat,  and  chopped 
as  finely  as  possible.  They  are  stirred  up  in  a  basin  with  a  large 
spoon,  150  c.c.  of  lukewarm  water  being  added.  The  fat  should  be 
mixed  with  the  mass  in  a  mortar  very  thoroughly  by  aid  of  a  warm 
pestle. 

Leube  claims  that  this  enema  is  unirritating  and  well  retained, 
and  that  the  fat  in  it  is  freely  absorbed  and  can  be  demonstrated  in 
the  cells  of  the  large  intestine  in  the  form  of  droplets.  No  starch 
should  be  added,  for  sugar  is  produced  from  it  so  rapidly  that  it 
irritates  the  mucous    membrane  of   the  bowel.     Others,  however, 

1  Raw-beef  juice  wcifcld  be  better. 

•  The  Scottish  Med.  and  Surg.  Jovrn.,  March,  1906,  xviii.  193. 


576  FOOD  AND  DIETETICS 

have  found  that  this  enema  results  in  a  great  deal  of  intestinal 
putrefaction,  and  even  in  some  degree  of  toxaemia. ^ 

O.  Griinbaum^  has  used  enemata  of  ox-serum  ^  with  success, 
2  grains  of  chloretone  being  added  to  each  ounce  of  the  serum  to  act 
both  as  a  sedative  and  a  preservative.  Ninety  c.c.  (3^  ounces)  may 
be  injected  every  four  hours,  which  yields  38  grammes  of  protein  in 
the  day.  By  the  addition  of  60  c.c.  (about  2  ounces)  of  milk  the 
total  protein  is  raised  to  51  grammes  per  day.  He  has  found  that 
such  enemata  are  very  well  absorbed. 

Rendle  Short  and  By  waters*  are  of  opinion  that  the  best 
nutrient  enema  is  one  composed  of  milk  pancreatized  for  twenty- 
four  hours,  with  the  addition  of  5  per  cent,  of  dextrose.  Goodall* 
uses  a  mixture  of  50  grammes  each  of  dextrose  and  alcohol  in 
1,000  c.c.  of  water.  An  enema  of  this  volume  is  completely 
absorbed  in  eight  hours,  and  yields  555  Calories.  Mutch  and 
Ryffel^  recommend  simply  a  5  per  cent,  solution  of  dextrose  in 
tap-water,  and  give  15  ounces  of  this  four  times  a  day. 

Recent  opinion  is  all  in  favour  of  using  these  simpler  enemata  in 
place  of  the  older  mixtures  containing  proteins  and  fat.  They 
appear  to  effect  all  that  can  be  achieved  by  rectal  feeding  without 
the  trouble  and  uncleanliness  of  the  more  elaborate  formulae. 


General  Technique. 

Enemata  should  be  given  at  the  body  temperature,  and  their  bulk 
should  not  exceed  250  c.c.  (about  9  ounces).  Fluids  should  be  given 
through  a  soft  oesophageal  tube  of  small  calibre,  introduced  as  high 
as  possible,  and  connected  with  a  funnel  raised  to  a  height  of  3  feet. 
Thicker  mixtures  (such  as  the  pancreas  enema)  should  be  adminis- 

Ewali's  Enema. 

2  tablespoonfuls  of  wheat  flour. 
5  ounces  of  lukewarm  water  or  milk. 
I  or  2  eggs  with  a  pinch  of  salt. 
Beat  up  with  2  to  4  ounces  of  a  15  per  cent,  solution  of  glucose. 
Then  add  i  glass  of  claret. 

1  See  Edsall  and  Miller,  Univ.  of  Pennsyl.  Med.  Bull.,  January,  1903,  xv.  414 
(abstract  in  Brit.  Med.  Journ.,  Epit.,  1903,  83). 

-  28  grammes,  or  28  c.c.  =  1  ounce. 

3  This  would  be  contained  in  about  3  ounces  of  honey. 

*  Boiled  starch  is  too  thick  to  inject. 

5  Bial  {Arch.  f.  Verdamings,  1903,  ix.  433)  found  that  of  an  enema  containing 
10  per  cent,  of  peptone  50  per  cent,  was  absorbed,  but  that  by  the  addition  of 
10  per  cent,  alcohol  the  absorption  was  raised  to  66  per  cent. 


SUBCUTANEOUS  FEEDING  577 

which  means,  even  assuming  complete  absorption,  an  energy  value 
of  less  than  35  Calories.  The  absorption  of  such  suppositories  has 
been  found  in  some  cases  to  be  very  far  from  perfect.* 


Subcutaneous  Feeding. 

The  injection  of  nutritive  substances  under  the  skin  may  be 
regarded  as  the  latest  method  of  administering  food  artificially.  It 
was  first  introduced  by  Menzel  and  Perco  in  the  year  1869,'  but  has 
only  come  into  use  very  slowly  since  that  date. 

In  order  that  a  food  may  be  available  for  subcutaneous  adminis- 
tration, it  must  fulfil  three  conditions  : 

1.  It  must  be  capable  of  direct  assimilation. 

2.  It  must  be  unirritating. 

3.  It  must  be  of  such  a  nature  that  it  can  be  easily  sterilized. 
There  are  but  few  foods  which  meet  all  these  requirements. 
Most  proteins  are  unsuitable,  because  those  which  can  be  directly 

assimilated  by  the  tissues  are  not  easily  sterilized  without  under- 
going coagulation  ;  and,  on  the  other  hand,  those  which  can  be 
readily  sterilized,  e.g.,  peptones  and  albumoses,  are  not  directly 
appropriated  by  the  tissues,  and  even  act  as  poisons  to  them.' 

A  solution  of  egg  white,  even  supposing  it  to  be  assimilated, 
which  some  writers  deny,  is  difficult  to  prepare  in  a  sterile  form,  and 
is  apparently  apt  to  cause  damage  to  the  kidneys.* 

Serum,  however,  contains  proteins  in  a  form  in  which  they  can  be 
sterilized  without  much  difficulty,  and  which  are  directly  assimilable. 
If  serum  is  heated  to  55°  C,  it  becomes  opalescent,  but  does  not 
coagulate,  and  can  then  be  injected  without  danger.  * 

Reinach^  brought  round  children  who  were  very  much  exhausted 
by  diarrhoea  by  injecting  20  c.c.  of  ox  serum  under  the  skin  at  the 
sides  of  the  thorax.  This  quantity,  however,  contains  only  about 
ij  grammes  of  protein,  and  it  is  probable  that  the  injection  of  salt 
solution  would  have  an  equally  favourable  effect. 

^  Boas,  however,  puts  iQ_  a  claim  for  the  restricted  utility  of  nutrient  sup. 
positories  in  a  few  cases  ('  tjber  Nahrsuppositorien,'  Berlin.  Klin.  Woch.,  April  4, 
1910). 

^  For  the  history  of  subcutaneous  feeding,  see  Bauer,  '  The  Dietary  of  the 
Sick  '  (Von  Ziemssen's  '  Handbook  of  General  Therapeutics,'  vol.  i.),  p.  271,  and 
Leube  in  Ley  den's  '  Handbuch  der  Ernahrungstherapie,'  i.  513. 

3  See  Neumeister,  Deut.  Med.  Woch.,  1893,  xix.  866. 

*  See  Leigh  (' Nutritive  Infusions ')  iV^u;  York  Med.  Journ.,  1902,  Ixxvi.  368; 
Jackson  ('Subcutaneous  Injections  of  White  of  Egg'),  ibid.,  1902,  Ixxvi.  813)  ; 
and  Laborde  ('  De  I'Alimentation  Sous-cutanee  par  les  Matieres  Albuminoide?  '\ 
J.  de  Physiol,  et  de  Pathol.,  1900,  ii   700. 

°  Friedenthal  and  Lewandowsky,  Archiv.  /.  Anut.  undPhysiolog.,  1899,  53I» 

^  Berlin.  Klin.  Woch.,  March  20,  1899. 

37 


578  FOOD  AND  DIETETICS 

Horse  serum  contains  from  7^  to  8  per  cent,  of  protein,^  and  is 
a  more  suitable  form  for  administration  in  this  way.  Salter  2  has 
injected  as  much  as  100  to  120  c.c. ,  previously  heated  to  65°  C,  of  it 
under  the  skin  in  adults  without  any  bad  effects.  No  albuminuria 
appeared,  and  the  total  nitrogen  excretion  in  the  urine  was  increased. 
The  total  amount  of  protein  which  can  be  administered  by  this 
method,  however,  can  never  be  of  much  nutritive  importance. 

Carbohydrates  in  the  form  of  grape-sugar  are  easily  sterilized, 
and  can  be  directly  assimilated.  F.  Voit^  found  that  as  much  as 
60  grammes  of  grape-sugar  in  10  per  cent,  solution  could  be  injected 
under  the  skin  of  the  thigh  without  glycosuria  resulting.  Unfor- 
tunately, however,  sugar  solutions  are  irritating,  and  much  pain  and 
infiltration  are  apt  to  be  produced  at  the  site  of  injection.  Miiller,* 
for  instance,  injected  a  10  per  cent,  solution  under  the  skin  of  his 
own  thigh,  but  so  much  pain  was  produced  that  he  resolved  never 
to  try  the  experiment  again.  Leube^  states  that  at  most  15  to 
20  grammes  of  grape-sugar  can  be  injected  without  great  pain 
resulting.  Barker  ^recommends  the  injection  of  a  5  per  cent,  solution 
of  glucose  in  normal  saline  in  conditions  of  exhaustion  or  collapse 
before  or  after  operation.  A  litre  of  such  a  solution  may  be  given  in 
the  day,  500  c.c.  being  injected  at  a  time.  The  injection  is  made 
under  the  skin  near  the  axilla  through  an  ordinary  aspirating  needle 
connected  with  a  funnel  by  3  feet  of  rubber  tubing.  A  similar 
solution  may  also  be  used  intravenously.' 

Fat,  in  the  form  of  oil,  is  really  the  only  form  of  food  which  fulfils 
all  three  conditions,  and  accordingly  it  is  the  only  food  substance  which 
can  be  injected  under  the  skin  with  any  freedom.  The  dangers  of 
producing  fat  embolism  would  seem  to  be  imaginary.  Leube,  after 
a  very  considerable  experience,  has  never  seen  it  occur. 

Olive  and  sesame  oils  are  the  best  forms  to  use :  30  to  40  c.c. 
should  be  injected  with  a  10  c.c.  syringe  at  three  different  places,  the 
injection  being  performed  slowly  and  without  much  pressure,  and 
the  puncture  sealed  with  collodion.  Injection  should  be  performed 
only  once  a  day,  and  the  groin  is  perhaps  the  best  site  to  select. 

That  oil  so  injected  is  really  assimilated  is  evidenced  by  the  fact 

*  Szontagh  and  Wellmann.  Deut.  Med.  Woch.,  1898,  xxiv.  421. 
"  Guy's  Hospital  Reports,  1896,  liii.  241. 

'  Munch.  Med.  Woch.,  1896,  xliii.  717,  and  1897.  xliv.  851. 

*  Gumprecht,  Verhand.  d.  Cong.  f.  Inn.  Med.,  i8g8,  xvi,  124. 

•  Verhand.  d.  Cong.  j.  Inn.  Med.,  1895,  xiii.  418. 

•  Brit.  Med.  Journ.,  1902,  i.  770 

7  Kausch,  '  t;ber  intravenose  und  subkutane  Ernahrung  mit  Trauben- 
?ucker,'  Deut.  Med.   IVoch.,  January  5,  191 1. 


SUBCUTANEOUS  FEEDING  579 

that  the  excretion  of  nitrogen  is  lessened  by  it,^  and  post-mortem 
also  the  fat  is  found  to  have  disappeared  from  the  point  of  injection. 
If  the  oil  be  properly  sterilized,  no  local  irritation  is  ever  produced, 
and  the  injections  may  be  continued  for  as  long  as  four  weeks 
without  bad  results.  ^ 

Caird'  reports  a  case  of  stricture  of  the  oesophagus  in  which  the 
patient  was  going  downhill  under  enemata,  and  had  a  subnormal 
temperature.  Four  ounces  of  sterilized  olive  oil  were  injected  into 
the  gluteal  muscles  without  the  production  of  any  local  pain  or  dis- 
comfort, and  with  great  benefit  to  the  general  condition. 

Krueg  also  kept  a  lunatic  alive  for  twenty  days  without  loss  of 
weight  by  the  subcutaneous  injection  of  15  to  30  c.c.  of  olive  oil 
daily,*  and  other  observers  have  repeated  his  experience.^ 

There  can  be  no  doubt,  then,  that  feeding  by  means  of  the  sub- 
cutaneous injection  of  sterilized  oil  is  a  feasible  enough  proceeding, 
but  it  must  be  remembered  that  its  value  is  strictly  limited.  Recent 
experiments  by  Winternitz*  have  shown  that  fat  so  given  is  only 
very  slowly  absorbed,  and  that  it  cannot  supply  more  than  25  Calories 
to  the  body  per  day.  In  spite,  then,  of  the  apparently  favourable 
results  reported  above  the  use  of  fat  for  subcutaneous  feeding  must 
be  pronounced  almost  useless. 

The  subcutaneous  administration  of  yolk  of  egg  has  recently  been 
practised  by  Muggia'  in  cases  of  malnutrition  in  infants  and  as  a 
substitute  for  lecithin.  The  injection  is  prepared  by  mixing  the  yolk 
of  a  fresh  egg  with  one-third  of  its  weight  of  normal  saline  solution. 
The  mixture  is  stirred  with  a  glass  rod  in  a  previously  sterilized 
vessel,  and  then  strained  through  gauze.  The  initial  dose  is  i  c.c, 
the  injections  being  made  in  the  buttock  or  lumbar  region.  There 
is  no  local  or  general  reaction  provided  aseptic  precautions  are 
observed.  Gentle  massage  is  performed  after  the  injection.  The 
quantity  at  each  injection  may  be  gradually  increased  up  to  10  c.c, 
but  one  should  not  go  above  that.  He  states  that  the  general 
nutrition  and  condition  of  the  blood  are  improved  more  rapidily  under 
this   treatment   than   under   lecithin.      G.   d'Errico,^  however,   has 

1  G.  Sommer,  '  Stoffv/echselversuch  mit  Subcutaner  Fettinjection  am  Men- 
schen,'  Sitzungsber.  d.  Physih.  Med.  Gesell.  zu  Wurzburg,  ibj-j,  26. 

*  See  Jacob,  quoted  by  Gumprecht,  Verhand.d  Cong.  f.  Inn.  Med.,  1898,  124. 

*  Edin.  Med.  Journ.,  September,  1893. 

*  See  Lilienfeld,  Zeit.  f.  Diiit.  und  Physik.  Therapie,  ii.  209. 

*  For  example,  Fornace  and  Micheli,  Rif.  Med..  July  14  and  15,  1897  (abstract 
in  Brit.  Med.  Journ..  Epit.,  September  11,  1897). 

«  '  Zur  Frage  der  Subcutanen  Fetternahrung,'  Zeit.  /.  Klin.  Med.,  1903,  1.  80. 
See  also  Henderson  and  Crofutt,  Amer.  Journ.  of  Physiol.,  1905,  xiv     193. 
'  Bnt.  Med.  Journ.,  1899,  i.,  September  30. 

*  Qiornale  internaz.  delle  Scienze  Med.,  August  31,  1902, 


580  FOOD  AND  DIETETICS 

found  from  his  experiments  that  such  injections  produce  only  slight 
and  temporary  improvement,  whilst  the  use  of  larger  quantities  is 
apt  to  cause  grave  lesions  of  the  kidneys. 


Gavage  and  Forced  Feeding. 

Gavage  was  introduced  by  Debove  in  the  year  1881.*  The  term 
was  first  applied  to  the  method  of  introducing  food  into  the  stomach 
by  means  of  a  tube  in  cases  of  obstinate  vomiting.  Curiously  enough, 
food  so  introduced  is  often  retained  when  nourishment  swallowed  in 
the  usual  way  is  vomited  immediately.  The  meaning  of  the  term 
has  now  been  extended  so  as  to  cover  all  cases  in  which  food  is 
artificially  introduced  into  the  stomach  by  a  tube  in  excess  of  the 
demands  of  appetite,  a  proceeding  more  correctly  described  as  forced 
feeding. 

An  ordinary  soft  stomach-tube  is  employed,  and  it  is  only  necessary 
to  introduce  it  into  the  upper  part  of  the  oesophagus  ;  it  need  not 
enter  the  stomach  proper.  If  the  pharynx  be  very  sensitive,  it  may 
be  previously  anaesthetized  by  cocaine. 

A  mixture  consisting  of  i  or  2  pints  of  milk,  3  beaten-up  eggs, 
and  3  ounces  of  milk-sugar  will  be  found  very  suitable  for  adminis- 
tration in  this  way.  Dujardin  Beaumetz  speaks  very  highly  of 
powdered  meat,  of  which  he  gives  100  to  400  grammes  daily,  stirred 
up  in  milk,  chocolate,  or  soup. 

A  daily  ration  consisting  of  3  pints  of  milk,  to  which  have  been 
added  3  ounces  of  milk-sugar  (previously  dissolved  in  water  by 
boiling),  ^  pint  of  cream,  and  a  pint  of  soup  strengthened  by  some 
protein  preparation,  such  as  Nutrose,  Plasmon,  Tropon,  or  powdered 
meat,  will  be  amply  sufficient  to  maintain  the  nutrition  of  a  patient 
who  is  confined  to  bed,  and  is  very  easily  administered  by  the  tube. 

*  See  Dujardin  Beaumetz,  Clinique  TherapeiUique,  i.  403. 


INDEX 


'  Abdominal  plethora,'  grape  cure  in, 

257 
Abel,  on  action  of  alcohol  on  heart  and 
circulation,    343 
on  restricted  use  of  alcohol,  350 
Absorbability  expresses  physiological 

digestibility' ,  9 
Absorption:  from  mixed  diet,  12,  13 
individual  differences  in  capacity 

for,  14 
influence  of  mineral  matters  on.  286 

of  water,   301 
of  alcohol  by  stomach,  339,  3G0 
of  bran,  incomplete,  213 
of  bread,  209 

relative,  of  white  and  whole- 
meal bread,  210 
of  carbohydrates,  12 
of  carbohydrates  in  bread,   com- 
plete, 210 
of  cocoa,  331 
of  eggs,  158 
of  fat,  10 
of  fish,  82 
of  food  in  intestine,  429-431 

in  stomach,  428 
of  fungi,  imperfect,  267 
of  green  vegetables,  252 
of  human  milk  in  infant's  intestine, 

445 
of  koumiss  and  kephir,  142 
of  meat,  65,  68 
of  milk,  124 
of  nuts,  261 
of  porridge,  223 
of  potatoes,  24  t 
of  proteins,  10,  12 

in  bread    defective,  209 

in  wholemeal  bread,  212 
of  pulses,  232,  233 
of  rice,  complete,  220 
of  vegetable  foods,  165 

obstacles  to,  166,  1&7 

proteins    difficult    to    absorb, 
109,  170,  173 

relative,  of  animal  and  vege- 
table foods,  166 

of  wholemeal  bread,  211,  213 

defective,  212 


Acetonuria,  500 

Achylia,  dietetic  treatment,  530,  533 
Acid,  acetic,  basis  of  vinegar,  286 
in  wine,  374.  377 
oxalic,  in  food,  297 
phosphoric,  in  food,  295 
Acidity  of  foods,  299 

of  gastric  contents,  413 

relation  of,  to  morbid  gastric  sen 

sations,  421 
total  in  sound  wine,  377 
Acids,  action  of,  in  wine,  392 
in  meat,  60 

fixation     and     neutralization     by 
casein,  144 
Adonis,  natural  mineral  water,  310 
Adult    diet,    comparison    with    infant 

diet,   446 
Adulteration  of  bread,  206 

of    wheat-flour    with    maize-flour, 
224 
Aerated  bread,  199,  220 
milk,  121 
waters,  artificial,  306-308 

danger  of  distilled  water,  309, 

310 
recipes  for,  30S 
varieties,  307 
Agassizt  belief  that  fish  was  specially 

good  for  brain,  83 
Age,  influence  on  amount  of  food,  45 
of  children,  food  at  different  ages, 
476,  477,  478.     See  also  Old  age 
Akoll  biscuits  in  diabetes,  497 
Aladdin  Oven,  410 
Albene,  preparation  of  nuts,  260 
Albulactin,  459 

Albumin,  average  daily  secretion  of,  in 
subacute    nephritis    under    dif- 
ferent diets,  541 
in  milk,  541 
Albuminuria,  transient,  how  produced, 

53 

Albumoses,  incapable  of  exciting  gas- 
tric secretion,  418 

Albuminoids    in    dietary    of    diabetes, 
151,  489 

Alcohol  (ethyl  alcohol),  337-395 
absorption  of,  339,  340 


581 


582 


FOOD  AND  DIETETICS 


Alcohol,  amount  for  daily  consumption, 
348 
as  food,  344,  345,  346 
as  a  stimulant,  340-344,  391 
avoidance  in  renal  disease,  541 
chemical  composition  of,  337 
efiects  of.  on  the  brain,  338,  340, 

342 
local,  on  tissues,  337 
on  circulation,  340,  342 
on  digestion,  338 
on  dilated  stomach,  340 
on  heart,  340-344,  351 
on  metabolism,  344 
on  salivary  digestion,  338,  369 
on  temperature  of  body,  342, 

345 
on  stomach  peristalsis,    338, 

339 
on  human  milk,  440,  441 
physiological,  337-352 
fat-sparer,  344,  345 
forbidden  in  chronic  nephritis,  544 
idiosyncrasy   in   consumption    of, 

349 
in  bread,  199 
in  koumiss  and  kephir,  141 
in  wine,  374,  376,  385 
produced  by  sugar  fermentation. 

278,  279 
proportion  of,  in  beverages,  354 
protoplasm  poison,  344 
question  whether  a  protein-sparer, 

346 
relation  to  immunity,  351 
requires  no  digestion,  340 
use,  in  diabetes,  498 
in  disease,  351,  370 
in  fattening  diets,  509 
in  fever  and  acute  fevers,  343, 

346.  351,  480,  484-486 
in  health,  349 
in  neurasthenia,  516 
in  obesity,  370,  511 
Alcoholic  beverages.     See  Beverages 
.'  Icoholism,  347 

vegetarian    and    lacto-vegetarian 
diet  for,  550 
Ales.  364-371 

mild  and  bitter,  366 
sugar-free,  371 
Aleuronat,  561 

home-made    diabetic    bread    pre- 
pared from,  497 
mixture  with  flour,  216 
Algae  as  food,  26S.     See  also  Irish  (or 

Carraigeen)  moss 
Alkalies,  addition  to  milk,  121,  122 
Alkalinity  of  foods,  299 
Allen,  caffeine  and  tannin  in  tea,  317 
composition  of  sausages,  75 


Allen,  fusel-oil,  356,  363 

meat  -  extract     containing     meat 
fibre,  96 
Allenbury  Foods,  468  Table 
Malted,  468  Table 
Allspice,  286 
Almonds  as  fat  food,  570 

nutritive  value  of,  262 
Alpine  climbing,  sugar  as  muscle-food 

in,  284 
Alum  whey,  132 
'  Amanita,'  toxin  of  fungi,  2O3 
America,  chemical  composition  of  mill- 
ing products  obtained  in,   m^ 
modification  of  cow's  milk  lor  in- 
fants, exact  science  in,  459 
Amino-acids,  571 
Amino-bodies,  77 
Amy  lose,  161 
Anaemia,  zomotherapy  in,  556 

in  relation  to  iron  in  foods,  293 
Aneurysm,  dietetic  treatment,  540 

restriction  of  water  in  diet  in  case 
oi.  303 
Aniline,  colouring  matter  of  sweets,  276 
Animal  foods,  58-75 

mixed,  and  vegetable  diet,  relative 

bulks,  167 
and  vegetable  foods,  relative  ab- 
sorption. 166 
preponderance  of  protein  in,   172 
note 
Animals,  analytical  feeders,  184,  346 
Anstie,  food  value  of  alcohol,  3 78 

wines  in  health,  395 
Antiseptic     action    of     gastric     juice, 

427 
Antiseptic,  intestinal,  milk  as,  126 
Aphrodisiac  properties  of  fish  diet,  83 
ApoUinaris,    natural     mineral     water, 

309 
Appetite,  416,  417 
definition,  416 

provoked  by  artificial  concentrated 
foods  in  illness,  563 
by  peptone  preparations.  563 
Arctic    Regions,    amount   of   food   re- 
quired in,  49,  50 
alcohol  in,  343 
Armour's  Beef  Juice,  loi,  102 

Soluble  Beef,  loi 
Arrowroot,  246 

addition  to  milk  in  fever  diet,  487 
British,    prepared     from    potato- j 

starch,  239 
chemical  composition,  246 
digestibility,  246 
economic  value,  247 
nutritive  value,  247 
See     also     Bermuda     arrowroot,] 
Farina,  Tons  les  mois 


INDEX 


583 


Arterial   tension   high,    dietetic   treat- 
ment, 540 
Arthritis,  rheumatoid,  diet  in,  519 
Artichokes,  243 

in  mild  diabetes,  245 
iniilin  in,  245 
Artificial   feeding,    559-570.     See   also 

Gavage 
Artificial  foods,  559-570 

degree  of  concentration,  559. 

560 
physiological  defence,  560 
suggestive   value   to   provoke 

appetite,  561 
carbohydrate,  honey,  567 
malt-extracts,  566,  567 
milk-sugar,  568 
fatty,  568-570 

cod-liver    oil    emulsions, 

569 
Cremalto,  569 
Lipanin,  569 
Miol,  569 

Pancreatic  emulsion,  569 
spermaceti,  570 
Virol,  569 
protein,  digested,  or  peptone 
preparations,       562- 
566 
Aleuronat,  561 
Carnrick's  Peptonoids, 

564 
Glidene,  561 
home-made  peptonized 

food,  566 
legumin,  561 
Mosquera    beef  -  meal. 

107 
pemmican,  561 
plantose,  561,  562 
Roborat,  561 
Somatose,  563 
Tropon,  562 
See  also  Infant  foods 
undigested,   561 
Ascites  of  cirrhosis,  salt-free  diet  in,  557 
Ashby's  method  for  preparing  human- 
ized milk,  458 
whey  for  infants,  458 
Asparagin  in  potatoes,  242 

in  asparagus,  249 
Asparagus,  asparagin  in,  249 
Ass,  rarely  suffers  fromtuberculosis,  450 
Ass's   milk,    comparison    with   human 
milk,  449 
composition,   449 
Assimilation,  function  of,  regulated  by 
central  nervous  system,  51 
of  sugars,  279 
Athletes,  dietaries  for,  38-41.     See  also 
Training 


Atkinson's,  Dr.  Edward,  Aladdin  Oven, 

410 
At  water,  absorption  of  mixed  diet,  13 
analyses    of    different     forms     of 

bread,  202 
diets  of  childhood,  45 
experiment     as     to     influence     of 
mental  work  on  food  required, 

41 
food  value  of  alcohol,  346  note 
standard  dietaries,  31 
standards  of  numbers  of  calories 

for  different  work,  36 
table  of  actual  dietaries,  32 
Australian  wines,  382 
Avenine,  221 

Aylesbury  Dairy  Company,  analyses  of 
humanized  milk,  456 

Backhaus,  Dr.,  on  foreign  matters  in 
milk,  117 
modification  of  cow's  milk,  459 
Bacon,  digestibility,  68 
Bacteria,  agency  in  '  ripening  '  cheese, 

147 
pathogenic,  in  milk,  116-118 
restraint  of  destruction  of  proteins 

in  intestine  by,  13 
role  of,  in  intestinal  digestion,  430 
Bailey's  Cooker,  407 
'  Bain-marie,'  slow  cooking  apparatus, 

407 
Baking  of  meat,  400 
Baking-powders,  200 

chemical  composition,  200 
'  Ballast,'  stimulus  to  peristalsis  of  in- 
testine, 13.  168,  189,  251,  536 
Bamberger,  fluids  in  chronic  nephritis, 

544 
Banana,  257,  258 

bulkiness  of,  257 
economic  value,  258 
percentage   of   chemical   composi- 
tion, 257 
Banana-flour,  2 58 

chemical  composition,  258 
nutritive  value,  258 
Bananina,  258,  468  Table 
Bananine  Bread,  205 
Banks  Company's  ales,  371 
Bannister,  analyses  of  tea.  316 

on  composition  of  raw  and  roasted 
coffee,  322 
Banting  diet,  504 

risks  of,  506 
Bardswell  and  Chapman  on  dietetics  of 
phthisis,  514 
meat  diet  in  phthisis,  514 
Barker    on    glucose    in    subcutaneous 

feeding,  578 
Barley,  226 


5«4 


FOOD  AND  DIETETICS 


Barley,  chemical  composition,  227 
Barley-sugar,  274 
Barley-water,  227 

dilution  of  milk  with,  to  aid 
digestibility,  121 
'  Barm  '  used  in  fermentation  of  Scotch 

bread,  198 
Barrie's  bitter  beer,  371 
Baumm,  composition  of  human  milk, 

439 
nursing  mother's  diet,  440 
Bean,  broad  or  Windsor,  235.     See  also 
Butter  bean,  Kidney  bean.  Soy  bean. 
Scarlet  runner 
Beans,  235 

avoidance  in  gout,  511 
rich  in  sulphur,  231,  232,  235 
Beaumont,  visible  observation  of  diges- 
tion in  case  of  Alexis  St.  Martin,  424, 

433 
Beef,  digestibility,  67 

raw  and  boiled,  composition  of,  65 
Beef-extracts,  02 

composition,  97 
containing  meat-fibre,  97 

claim  to  be  regarded 
as  food,  97 
Beef-juices,  99 

amount  of  coagulable  protein 

in.  loi 
artificial  composition  of,  102 

expensive,  102 
contain  protein  in  coagulable 

form,  108 
objections  to,  102 
See     also     Bovinine,     Bovril 
Company's  juices.   Brand's 
Essence,      Liquor     Carnis, 
Raw    Beef-juice,     Taurine, 
Wyeth's  Beef-juice 
Beef-powders,  107,  108,  109.     See  also 
Mos(]uera     Beef  -  Meal,     Pemmican, 
Somatose 
Beef-tea,  103 

composition   and    uses,     105, 

106 
method  of  preparation,    104, 

preparations,  composition  of, 

107 
value  exaggerated,  106 
whole,  106,  109 
See  also  Brand's  Fibrous  Beef- 
tea,    Mason's   Strong   Beef- 
tea,  Vril  Albuminous  Beef- 
tea 
Beer,  364-371 

German,  350,  365,  367 
non-alcoholic,  371 
stone  ginger-beer,  308 
'  substitute  '  beer,  367 


Beetroot,  244 

rich  in  cellulose,  244 
sugar  in,  244 
Beet-sugar,  272 

chemical  composition.  273 
difference  between  cane-sugar 
and,  273 
Bell,  chemical  composition  of  bread,  202 
Bendle's  Meal  Port  Nutrient,  389 
Benger's  Food,  468  Table,  470,  483 

in  fever  diet,  483 
Bergeat,    comparative    absorption    of 

offal,  74 
Beri-beri,  cause  of,  18 
Berina,  Montgomerie's,  221 
Bermaline  Brown  Bread,  204 

composition,  203 
Bermuda  arrowroot,  246 
Beverages — 

alcoholic,  253-371 

beer  and  ale,  364-371 

brandy,  357 

German  beers,  365,  367,  36S 

gin.  359 

liqueurs  and  bitters,  360 

malt  liquors,  364-371 

moderate  use  permitted  in 
atonic  and  flatulent  dyspep- 
sia, 532 

porter  and  stout,  367 

rum,  358 

spirits,  353-364 

whisky,  355-357 

wines,  372 

in  children's  diet,  476 

in  constipation,  536 

in  diabetes,  371,  493,  49'S,  499 

in  gout,  370,  518 

in  obesity,  370,  371,  511 
non-alcoholic,  371 
Biedert's  cream   mixture   for   infants, 

455.  456 
Biliousness,  dietetic  treatment,  538 
Binz  on  effect  of  alcohol  on  stomach 
peristalsis,  338 
on  crude  spirits,  364 
Biogene,  144 

home-made    diabetic    bread    pre- 
pared from,  497 
wafers  in  diabetes,  497 
rusks,  475 
Biscuits,  206,  207 

chemical  composition,  206 
digestibility.  209 
See  also  Ship's  biscuit 
Bitters,  360 
Bivo,  389 
Black  bread  (Pumpernickel),  197 

wasteful  food,  228 
Blane,  Sir  Gilbert,  on  potato  in  scurvy, 
236 


INDEX 


58s 


Bloater,  nutritive  value  high,  84 
Blood,  abundant  supply  necessary,  41 
expenditure  in  digestion  of  bulky 

diet,  180 
influence  of  water  on  volume  of, 

301,  302 
preparation  from.     See  Beef-juice 
toxic  material  in,  causing  marginal 
gingivitis,  418,  642 
Blood-substance  not  valuable  as  food, 

72 
Blubber,  consumption  in  large  amounts 

by  Esquimaux  explained,  50 
Blyth,  A.  Wynter,  analysis  of  barley- 
water,  227,  228 
Boas's  enema,  575 
Boat  crews,  dietaries  of,  40 
Bohea  tea,  314 
Bomer  and  Konig,  analysis  of  Liebig's 

Extract,  93 
Boiling,  398 

effects  on  milk,  116 
of  eggs,  398 
of  meat,  398 
Bones,  composition  of,  78 

in  production  of  gelatin,  78 
Boussingault,  economic  value  of  pota- 
toes, 242 
iron  in  food,  292 
staleness  of  bread,  205 
Boutroux  on  staleness  of  bread,  206 
Bovinine,  loi 
Bovril,  97 

Bovril  Company's  meat-juices,  loi,  102 
Bovril  Wine,  389 

Bowels,  distension  from  bulky  diet,  179 

koumiss  in  chronic  catarrh  of,  143 

Boyce   and    Herdman,    '  greening  '    of 

oysters,  87 
Brain,  effect  of  alcohol  on.  340,  342,  343 
fish  not  valuable  as  brain-food,  83 
importance  of  digestibility  of  food 

to  brain-worker,  42 
phosphorus  as  brain-food,  41 
Brain-substance  as  article  of  food,  74 
Bran,  incomplete  absorption,  210,  213 
of  wheat,  190,  192 

alone  removed  by  stone  grind- 
ing, 192 
retained    by    '  Frame    Food  ' 
process,  195 
Brandl,  digestibility  of  sugar.  277 
Brand's  Essence,  96,  loi,  roa 

Fibrous  Beef-tea,  chemical  compo- 
sition, 107 
Brandy,  357 

in  fevers,  486 
'  Braxy  '  mutton,  explanation  and  use 

of,  70,  71 
Bread,  196-218 

absorption,  209 


Bread,    absorption,   relative,    of  white 
and  wholemeal  bread,  210 
addition  of  meat  to,  215 
adulteration,  206 
alcohol  in,  199 
and  skim  milk,  128 
carbohydrates    in,    complete    ab- 
sorption, 210 
changes    consequent    on    keeping, 

205 
chemical  composition,  201,  205 
cooking  of,  206 
diabetic.  496,  497 
digestibility,  208 
economic  value  of,  217 
jelly,  method  of  preparing,  472 
least  bulky  of  vegetable  foods,  lOO 
'  leavening,'    or   fermentation    by 

yeast,  196,  197 
-making, '  sponge '  formation  in.igS 
gluten  in  flour  necessary  for, 
196 
malting  of,  204 
mineral  matters  in,  210 
moisture  in,   standard  should  be 

fixed,  201 
nutritive  value,  215,  216 
protein   in,    defective   absorption. 
209 
method  of  increasing,  215 
staleness,  205,  206 
waste  in  bread-making,  199 
white,  comparative  composition  of 
crust  and  crumb,  205 
compared  with  Graham  bread 
and  entire  wheat  bread,  212 
compared  with  wholemeal,  15 
See  also  Aerated  bread,  Bermaline 
brown    bread.     Brown     bread. 
Entire     wheat     bread,      Hovis 
bread,     Manhu     bread,     Turog 
bread,    Vienna    bread,    Whole- 
meal bread 
Bread   Reform   League   directions   for 

bread-making,  211 
Breads,  fancy,  204 
malted,  204 
patent,  204 
Brewing,  365 
Bri gilt's  disease,  dietetic  treatment,  543. 

See  also  Nepliritis 
Brillat-Savarin.  aphrodisiac  properties 
of  fish  diet,  83 
instance  of  enormous  consumption 

of  oysters,  87 
sugar  as  a  muscle-food,  2S2 
Broad  bean,  235 
Bromose,    commercial   preparation   of 

nuts,  260 
Bronchial  catarrh,  grape  cure  in,  257 
Brose,  223 


586 


FOOD  AND  DIETETICS 


Brown  bread,  201 
cellulose  in,  202 

poorer     in     carbohydrates     than 
white,  202 
Brown,  E.  W.,  Iceland  moss,  269 
Bruce,  Dr.  J.  Mitchell,  milk  diet  in  sub- 
acute nephritis,  543 
on  milk  in  nephritis,  543 
Brunton,  Sir  Lauder,  and  TunnicUffe, 
F.  W.,  researches  on  digestibility  of 
bread,  213 
Biichner  on  phosphorus  as  brain  food, 

41.83 
Buckle,  costliness  of  highly-carbonized 

food,  16 
Buckwheat,  229,  230 
Budin's    method    of    preparing    cow's 

milk  for  infants,  453 
Build  of  body  and  amount  of  food,  44 
Bulgarian  bacillus  in  sour   milk   pre- 
parations, 558 
acclimatization    in    intestine. 
558 
Bulkiness  of  vegetable  foods,  164,  166, 
178 
obstacle  to  complete  digestion 

and  absorption,  167 
physiological  effects,  179 
of  banana,  257 
of  potatoes,  242 
Bulkley,   dietetic  treatment  of  psori- 
asis, 547 
Bullen,  F.  T.,  method  of  cooking  prac- 
tised by  Kanakas,  411 
Bunge,  on  dangers  in  dietetic  use  of 
sugar,  282 
on  iron  in  food,  291 
on  salt  craving,  165,  295 
Burgoyne's  Meat-juice,  loi 
Burgundy,  373,  381 
Burton  ale,  composition,  365,  367 

analysis,  368 
Busch,   time  of  escape   of   food   from 

stomach,  423 
Bushuyez's  typhoid  fever  diet,  487 
Butter,  134 

compared  with  jam,  136,  137,  476 

digestibility  easy,  135 

fat  in,  134,  570 

nutritive  value  of  margarine  nearly 

equals  that  of,  136 
preservation  of,  134 
substitutes     for,     prepared     from 
nuts,  260 
Butter-bean,  232 
Butter- milk,  122,  138 

cheap  source  of  protein,  138 
chemical  composition,  138,  141 
diuretic  properties,  13S 
Butyric  acid,  135 
Bynol,  569 


Cabbage.  249,  250 

valuable  antiscorbutic,  252 
Caffeine  in  tea,  317-320 

effect  on  tissue  waste,  329 
source  of  uric  acid,  335 
stimulating  action,  329,  332 
Caird  on  subcutaneous  injection  of  oil, 

579 
Calcium  casein,  115 
in  milk,  290 
in  yolk  of  egg,  155 
sources  and  function  of,  2 88 
paracasein,  115,  120 
Calf's-foot  jelly,  76,  78 
Calif ornian  wines,  382 
Calorie  standard,  4 

method  of  application,  6 
value  of  different  foods,  426,  508 
of  human  milk,  446,  447 
Calories,  amount  required  for  work  of 
different  degrees  of  severity,  35, 
36,  43 
large  number  yielded   by   sugar, 

281 
obtained  from  bread,  217 
percentage   lost   through   non-ab- 
sorption, II 
reduction  in  obesity  diet,  503,  504 
Camerer,  daily  amount  of  human  milk, 

442 
Cameron,     Miss     I.     D.,     dietary     of 
students'  halls  of  residence  in  Edin- 
burgh, 34 
Cane-sugar,  270 

avoidance     in     hyperchlorhydria, 

531 
chemical  composition,  271,  273 
difference  between  beet-sugar  and, 

273 
early  records  of,  270,  271 
proportion     in     commercial     and 
home-made  jams,  276 
Cannon,  movements  of  pyloric  end  of 

stomach,  422,  423 
Caramel,  conversion  of  sugar  into,  397 
Carbohydrate  foods,  artificial,  566-568 
Carbohydrates,  absorption,  12 
amount  required  in  diet,  26 
and  fats  increase  in  fattening  diets, 

512 
as  protein  sparers,  23 
as  sources  of  muscle  energy,  37 
brown  bread  poorer  in,  than  white, 

202 
constituent  of  milk,  milk-sugar,  or 

lactose,  no 
degree   of  concentration  possible, 

560 
effect  of  heat  on,  396 
foods  rich  in,  sparing  use  in  hyper- 
chlorhydria,  531 


INDEX 


587 


Carbohydrates     in     bread,     complete 
absorption,  210 
in  cereals,  189,  493 
in  diabetes  diet,  488-492 

question  of  restriction,  408 
in  diet  of  infancy,  435 
in  fniit,  254,  493 
in  green  vegetables,  250,  493 
in  milk  products,  493 
in  pulses,  493 

abundant,  232 
in  rectal  feeding,  572 
in  roots  and  tubers,  493 
in  subcutaneous  feeding,  578 
in  vegetable  foods,   16,   161,    185, 

493 
intestinal,  572 

of   mixed   diet,   restraining  effect 
upon  destruction  of  proteins  by 
putrefactive  bacteria,  12 
restraining  effect  upon  intestinal 

putrefaction,  430,  431 
sources  of,  in  child's  diet,  476 
time  of  stay  in  stomach,  425 
Carbon  food  cycle,  181,  182 
Carbonaceous  foods,  limitation  in  head- 
aches, 546 
Carbonic  acid,   excretion  during  rest, 

42 
Carbonic  acid  gas,   dietetic  disadvan- 
tages of,  310 
aid  to  digestion,  310 
Cardiac  disease.     See  Heart  disease 
dropsy,  539 

dry  diet  in,  539 
Carlsbad,  gout  dietary  at,  517 
Carnine    and     carnic    acid    in    meat 
extracts,  94 
Lefrancq,  loi,  102,  556 

dosage,  556 
soluble  food,  467 
Carnrick's  peptonoids,  564 

soluble  food,  468  Table 
Carraigeen  moss.     See  Irish  (or  Carrai- 

geen)  moss 
Carrots.  10,  244 

rich  in  sugar,  244 
Carr's  '  Oaten,'  221 
Casein  bread  in  diabetes,  497 

combination  of,  in  Plasmon  cocoa, 

335 
contains  phosphorus,  144 
dietetic  advantages,  144 
in  milk,  no,  115,  451 

digestibility,    method    of    in- 
creasing, 454.  455 
digestion  difficult,  120,  141 
intestinal  absorption,  571 
nutritive  value,  144 
precipitation  in  making  of  cheese, 
146 


Casein,  preparations,   1.13-145 

enrich    diet    in    protein,    145 
note 
See  also  Casumen,  Nutrose,  Plas- 
mon    (and     Plasmon     prepara- 
tions),  Protene  Diabetic  bread, 
Protene  flour,  Sanatogen 
Caseinogen,  115 
Cask,  wine  in  the,  374 
Casoid  bread,  and  casoid  meal  bread, 

in  diabetes,  497 
Cassia,  286 
Castor  seeds,  vegetable  protein  in  pure 

form  from,  538 
Casumen,  addition  to  milk  in  fever  diet, 

483.  487 
preparation  of  casein,  144,  561 
Cathcart's  apparatus  for  milk  steriliza- 
tion, 118 
Cauhflower,  rapid  digestion  of,  425 
Caviare  as  article  of  diet,  85 
Cayenne  pepper,  286 
Cellulose,  beetroot  rich  in,  244 

cause   of  defective  absorption  of 

wholemeal  bread,  212 
digested  in  experiments  with  men, 

168 
effect  of  cooking  on,  401-404 
in  brown  bread,  202 
in  fruits,  255 
in  vegetable  foods,  161,  162,  166, 

167 
onions  rich  in,  245 
useful  as  intestinal  stimulant,  168, 
169 
Celsus,  therapeutic  value  of  milk,  130 
Cerealine,  chemical  composition,   225 

preparation  of  maize,  225 
Cereals,  187-230 

carbohydrates  in,  188 

chemical    composition     of,      188, 

189 
fat  in,  188 

mineral  matter  in,  188 
preponderance,  189,  493 
products  derived  from,  190 
proteins  in,  187 
Cerebos  salt,  296 

Chambers,  T.  King,  evils  of  deficient 
diet,  57 
fusel  oil,  363 

relaxation  after  meals,  433 
whole  beef -tea,  106 
Champagne,  385 

in  fevers,  486 
Chapman  and  Bardswell,   dietetics  of 
phthisis,  514 
meat  diet  in  phthisis,  514 
Chapman's  Whole  Wheat  Flour,  219, 

468  Table,  471 
Cheese,  146-150 


588 


FOOD  AND  DIETETICS 


Cheese,  action  of  rennet   on   milk   in 
formation  of,  146 
agency  of  bacteria  in  ripening,  147 
chemical  composition,  148 
digestibility,  148,  149 
flavour  of,  how  produced,  147 
hard,  146 

nutritive  value,  149 
precipitation  of  casein  in  making 

of,  146 
protein    and    fat    essential    com- 
pounds of,  147 
soft,  147 
soy,  236 
Cheltine  Infant's  Food,  468  Table 
Maltose  Food,  468  Table,  404 
Chemical  composition  of  alcohol,  337 
of  arrowroot  and  sago,  246 
of  baking-powders,  200 
of  banana,  257 
of  banana-flour,  258 
of  barley,  227 
of  biscuits,  206 
of  bread,  201-205 
of  butter-milk,  138 
of    cane-,   beet-    and    maple- 
sugar,  271,  273 
of    cereals,    and  •  of   products 
derived  from  cereals,    188, 
189 
of  cheese,  148 
of  chestnuts,  262 
of  chocolate,  328 
of  coffee,  raw  and  roasted.  323 
of  condensed  milk,  462,  /163 
of  custard-powders,  159 
of  Devonshire  cream,  133 
of  eggs,  152-156 
of  faeces,  425,  431 
of  fish,  78-So,  88,  89 
of    food    less    important    to 
brain- worker    than    diges- 
tibility, 42 
of  Fromm's  extract,  261 
of  fruit,  253,  254 
of  fruits  (dried),  259 
of  fungi,  265 

of  green  vegetables,  248,  249 
of  honey,  275,  567 
of  Iceland  moss,  269 
of  Irish  (or  Carraigeen)  moss, 

268 
of  Italian  pastes,  219 
of  johnny  cakes,  224 
of  maize  and  special  prepara- 
tions, 224,  225 
of  malt  liquors,  368 
of  margarine,  136 
of  meat,  61 
of  milk  (human),  473 
of  milks  (different),  443 


Chemical  composition  of  mill-products 
of  wheat,  194 
of  millet  (Indian),  229 
of  nuts,  259,  260,  262 
ol     patent     preparations     of 

wheat,  219,  220 
of  peptone  preparations,  565 
of  pop-corn,  225 
of  potatoes,  238,  241 
of  preparations  of  oats,  222 
of   proprietary   infant   foods, 

461-465 
of  pulses,  231,  234 
of  Revalenta  Arabica,  235 
of  rice,  228 

of  roots  and  tubers,  237 
of  tea,  315-318 
of  tea-infusion,  318-320 
of  vegetable  foods,  160-165 
of  wheat,  190,  191 
of  wholemeal  bread,  214 
of  wines,  375,  394 
Chemical  tests  of  value  of  food,  4 
Chestnuts,  chemical  composition,  261, 

262 
Cheyne,  G.,  on  the  advantages  of  purin- 

free  diet,  551 
Chicken,  digestibility,  68 
Childhood,   diet,    amount  of  each  nu- 
trient   ingredient   required 
at  different  ages,  474 
deficiency    in    protein    disas- 
trous, 175 
beverages,  476 

dietaries  and  meals,  477,  478 
ratio    of    protein    to    carbo- 
hydrates and  fat,  474 
requirements,  45,  46 
sources  of  carbohydrate,  475 
of  fat,  475 

of  mineral  matters,  476 
of  protein,  474 
use  of  sugar  in,  475 
Children,  favourable  influence  of  sugar 
on  health  and  growth  of,  282 
relative   values   for   food   require- 
ments at  different  ages,  45 
relatively  require  greater  amount 

of  food  than  adults,  45 
young,    absorb   milk   better   than 
adults,  125 
Chittenden,  amount  of  protein  required 
in  diet,  24,  176 
digestion  of  meat,  66,  67 
use  of  milk-powder,  462 
and  Cummins  on  digestibility  of 

fish,  82 
and  Mendel,  absorption  of  alcohol 
by  stomach,  3  ■^11 
analysis  of  Burton  pale  ale, 
368 


INDEX 


589 


Chittenden   and    Mendel,    analysis    of 
Guinness's  Dublin  stout,  368 
wine  and  digestion,  390 
Chlorine,  298 
Chocolate,  275.  328,  477 
as  fat  food,  570 
composition  of,  3  28 
Plasmon,  328 
Chorea,  dietetic  treatment,  546 
Church,    Professor,    analj'sis    of    corn- 
flour, 225 
analysis  of  Iceland  moss,  209 
analysis  of  Indian  millet,  229 
analysis  of  mill-products  of  wheat, 

194 
chemical   composition   of    wheat, 
190 
Cider,  387 
Cinnamon,  286 

Circulation,   stimulating  action  of  al- 
cohol on,  341-344 
disorders  of,  diet  in.  538-540 
Cirrhosis  of  liver,    dietetic  treatment, 

537.  537 
use  of  koumiss  in,  143 
Citrate  of  soda  added  to  milk  to  aid 

digestion,  121,  455 
Citric  acid  in  milk,  112 

in  tomatoes,  252,  298 
lemonade  in  diabetes,  498 
Clams  as  food,  88 
Claret,  373,  380  _ 
Clarke  and  Gushing,  hbernl  supply  of 

water  in  typhoid  fever  diet,  488 
Climate,  influence  on  amount  of  food. 

48 
Clothing  in  relation  to  food,  49 
Clotting  of  milk,  115 

distinguished    from    curdling, 

114,  115,  120 
in  stomach,  119    120,  121 
Cloves,  286 

Coagulation  of  milk,  114 
Cocacorn,  336 

Cocoa,  analysis  of  commercial  forms  of, 
327.  328 
allowed  in  diabetes,  498 
avoidance  in  gout,  551 
chemical  composition  of,  326-328 
digestion  and  absorption,  331 
food-value,  335 
homoepathic,  326 
malted,  326 
navy  cocoa,  326 
-nibs,  325 

-nuts,  nutritive  value,  261 
Plasmon,  335 
soluble,  325 
tannin  in,  327 
theobromine  in,  327 
Sec  also  Sanitas  Health  Cocoa 


Cocolardo,  commercial  preparation  of 

nuts,  260 
Cocoleum,  commercial  preparation  of 

nuts,  260 
Cocos  butter,  commercial  preparation 

of  nuts,  260 
Cod-liver  oil  emulsions,  569 
Coefficients  of  digestibility,  10 
Coffee,  322 

allowed  in  diabetes,  408 
avoidance  in  cases  of  gout,   335, 

beans,  varieties  of,  322 

chemical  composition  of  raw  and 

roasted,  323 
composition  of  infusion,  324 
French,  324 
history  of,  322 
influence  on  salivary  and  gastric 

digestion,  329-335 
injurious  effects,  327,  330 
Life-Belt,  336 
making  of,  324 
not  a  food,  334 
stimulating  action,  329 
Coffees,  cereal.  336 
Cohendy,  acclimatization  of  Bulgarian 

bacillus  in  intestine,  55S 
Cold,     resistance    to,     diminished    by 

under-feeding,  55 
Colitis,   acute  and  ulcerative,   dietetic 
treatment,  534 
muco-membranous,  dietetic  treat- 
ment. Von  Noor den's  meth- 
od, 534,  535 
Plombieres  system,  534 
Ransom's  dietary,  535 
Collagen,  59 

yields  gelatin,  59 
Colostrum,  437,  438 
Coma,  diabetic,  diet  in,  501 
Combustion  in  body,  4.  5 
Condensed  milk,  462-466 

chemical  composition,  462,  464 
digestibility,  464 
kinds  of,  464 

nutritive  value  and  economy,  465 
sweetened,  limitations  of  use,  459 
Condiments  and  spices,  284 

necessity  for,  284 
Congou  tea,  314 

Constipation,    chronic,    directions    foi 
diet.  534,  536,  537 
onions,  valuable  in,  245 
use  of  whey  in,  in  cases  of  nephri- 
tis, 133 
Contrexeville,   natural  mineral  water, 

310 
Convalescence,  fattening  diet  for,  513 
use  of  koumiss  in,  143 
zomotherapy  during,  556 


59° 


FOOD  AND  DIETETICS 


Cookery  of  flour,  196 

Cooking,   effect  of,  on  carbohydrates, 
396 
on  cellulose,  401-404 
on  digestibility  of  food,   390, 

396 
of  meat,  66,  67 
on  fat,  397 

on  green  vegetables,  250 
on  meat,  64,  66 

causes  loss  of  water,  64 
on  proteins,   396,   39S 
losses  in,  404 

method  of,  in  Salisbury  cure,  67 
of  bread,  206 
of  edible  fungi.  266 
of  fish,  400 
of  foods,  396-411 
of  fruits.  255,  256 
of  meat,  397-400 
of  potatoes,  239,  240 
of  vegetable  foods,  401-404 
retards  digestibility  of  meat,  66,  67 
slow,  407-411 

contrivances  for,  407-411 
vegetable  foods  require  long  time 
in,  185 
Coombs'  Malted  Food,  468  Table 
Corlette,  analyses  of  barley-water,  227 
Comaro,  temperance  in  old  age,  46 
Corn  flakes,  preparation  of  maize,  225 
Cornflour,  preparation  of  maize,  225 
Corn  Laws,  repeal  of,  hygienic  effects, 

55 

Corpulence.     See  Obesity 
Cow's  milk,  adulteration  of,  113,  114 
behaviour  of,  in  intestine  of  infant, 

453 
chemical  composition,  112,  141 

variability  in,  113 
chemical  differences   between  hu- 
man and  cow's  milk,  450 
density  of  clot  in  stomach,  453 
digestibility  of  human  and  cow's 
milk  compared,  452 
of  casein  in,  increased  by  add- 
ing citrate  of  soda,  121,  455 
fat  in,  452 
fermentation  of,  to  produce  kephir, 

140 
infant's  food  prepared  from,  467, 

470 
lecithin  in,  proportion  less  than  in 

human  milk,  451 
modifications  of,  for  infants,  453- 

460 
mineral   salts  in,   compared  with 

those  in  human,  452 
nitrogenous  matters  in,  451 
tuberculous,  117 
Crab  as  article  of  food,  85 


Cramer,  eggs  and  milk  as  protein  prO' 
ducers,  176 
results   of  observations   on   vege- 
tarians, 179 
Cream,  133 

allowed  in  diabetes,  496 
as  fat  food,  133,  134,  546 
mixtures  for  infants,  455,  456 
See  also  Devonshire  cream 
Creamota,  221 

Creatin  in  meat  extractions,  94,  98 
Creatinin  in  meat  extractions,  98 
Cremalto,  chemical  composition,  569 
Crookes,  Professor,  loss  of  nitrates  tt 
soil,  and  method  of  fixing  free  nitro- 
gen, 183 
Cucumber,  250 

percentage  composition  of,  250 
Cummins  and  Chittenden  on  the  diges- 
tion of  meat,  66,  67 
on  digestibility  of  fish,  82 
Curdling   of   milk   distinguished   from 

clotting,   115 
Cushing  and  Clarke,  liberal  supply  of 

water  in  typhoid  fever  diet,  488 
Custard-powders,     chemical    composi- 
tion, 159 
'  substitutes  '  for  eggs,  159 
Cyclone    \Vliolemeal    Bread    composi- 
tion, 203 
Cytos  Brown  Bread,  composition,  203 

Dancel,  restriction  of  fluids,  509,  510 

Daren  Brown  Bread,  composition,  203 

Date  as  food,  259 

Dauglish's  method  of  preparing  aerated 
bread,  199 

Debility,  zomotherapy  in,  556 

Delirium     tremens,     koumiss     recom- 
mended in,  143 

Dennig  on  influence  of  water  on  ab- 
sorption, 304 

D'Errico,  subcutaneous  administration 
of  yolk  of  egg,  579 

Devonshire  cream,  133 

chemical  composition,  133 
use  in  diabetes,  133 

Dextrin  prepared  from  potato  starch, 

239 

in  vegetable  foods,  162 
Dextrose,  or  grape-sugar,  274,  372,  576 
Diabetes,  alcohol  in,  352,  49S 

artichokes  in,  245 

avoidance  of  junket  in,  115 

beverages,  352,  498 

carbohydrates  in,  498 

chemical  substitutes  for  sugar  used 
in,  287 

diet  in  diabetic  coma,  501 

foods  available,  as  sources  of  albu- 
minoids, 494 


INDEX 


591 


Diabetes,   foods,    carbohydrates,    492, 

493 
fat,  491 
proteins,  491 
increase  of,  in  relation  to  increased 

consumption  of  sugar,  2 82 
laevulose  in,  498 
meals,  499 
no  fixed  diet  for,  491 
oyster  forbidden  in,  86,  87 
pea-nut  as  food  in,  236 
restriction  of  carbohydrates.  488- 

492 
richness  in  fat,  490 
soy  bean  in,  235 
tea  allowed  in,  498 
toast  to  be  avoided  in,  497 
turnips  need  not  be  forbidden  in, 

244 
use  of  Devonshire  cream  m.  133 
fruit  and  fruit-carbohydrates 

in,  254,  498 
milk  in,  494,  495 
test  diets  in,  496 
Diabetic  breads,  496,  497 

(home-made) ,  sources  for  prepara- 
tion, 497-  See  also  Casoid 
bread  and  Casoid  meal  bread, 
Protene  diabetic  bread,  Plasmon 
diabetic  biscuits 
(sugar-free)  milk,  preparation,  494, 

495 
'  Diamalt  '  with  cod-liver  oil,  569 
Diarrhoea,  acute  and  chronic,  diets  for, 

523.  533  .         .       , 

nervous,  no  special  diet  for, 

534 
acute,   of  infancy,   dietetic  treat- 
ment, 536 
causation  of,  by  meat  extractives 
in  large  amounts    108 
by  peptones,  563 
chronic,  result  of  purely  vegetable 

diet,  179 
infantile  diet  in,  536 
Diet,  mixed,  absorption  from,  12 

restriction    to    single    article    of, 

dangerous,  30 
salt-free,  556 
standard,  31 

application,  33,  34 
construction,  empirical  meth- 
od,  25 
physiological  method,  25 
Dietary  of  students  at  Edinburgh,  34 
Dietaries,  actual,  32,  33 
Digestibility,  coefficients  of,  10 

popular  and  physiological  sense,  8 
of  arrowroot,  sago,  tapioca,  246 
of  bacon,  68 
of  beef,  67 


Digestibility  of  biscuits.  209 
of  bread,  208 
of  butter,  135 

of  casein  in  milk,   method  of  in- 
creasing, 454,  455 
of  cheese,  148,  149 
of  chicken,  68 
of  condensed  milk.  464 
of  eggs,  157 
of  fish,  81,  82 

of  food,  more  important  to  brain- 
worker  than  chemical  composi- 
tion, 42 
of  foods,  effect  of  cooking  on,  396, 

404 
of  fruit,  256 
of  fungi  not  easy.  267 
of  game,  68 
of  gelatin,  77 

of  green  vegetables,  difficult,  251 
of  human  milk,  445,  452 
of  invert  sugar,  278 
of  koumiss  and  kephir,  141 
of  meat,  65,  67 

idiosyncrasy  in,  68 
retarded  by  cooking,  66,  67 
of  milk,  119-123 
boiled    and    unboiled,     com- 
pared,. 121,  122 
human  ai>d  cow's,  compared, 

452 
methods   of   improving,    120, 
121,  448 
of  mutton,  67 
of  nuts,  260 

of  oyster  easy  when  raw,  87 
of  pork,  68 
of  potatoes,  241 
of  pulses,  232 
of  rice,  229 
of  rye,  228 
of  rye  bread,  213 
of  starch  by  infants,  472 
of  sugar,  169,  277-279 
of  veal,  67,  68 
of  vegetable  foods,  165,  166 
obstacles  to,  166,  167 
Digestion,   action  of  malt  liquors  on, 
369 
action  of  spirits  on,  361 
aided  by  carbonic  acid  gas.  310 
diminished  by  underfeeding,  57 
in  intestine  more  important  than 

in  stomach  in  infants,  445 
in  large  intestine,  423 
in  mouth,  412 
in  stomach,  413 
influence  on,  of  alcohol,  338-340 
of  hunger  and  appetite,  416, 

417 
of  Liebig's  Extract,  95 


592 


FOOD  AND  DIETETICS 


Digestion,   influence  of  malt  extracts, 

567 
of  peptones,  562 
of  rest  and  exercise,  433 
of  salt,  294 
of  tea,  coffee,  and  cocoa,  329- 

335 
of  water,  303 
ot  wine,  390,  391 
intestinal,  429-431 

bacteria  in,  430 
of  casein,  120 

of  different  foods,  rate  of,  424-4^7 
of  food  in  health,  406,  427 

X-ray  observations  on,  420 
of  meat,  65,  66 
of  milk,  how  aided.  120,  121 
of  mixed  meal  process  summarized, 

431.  432 
of  starch  in  stomach,  414 
rate  in  case  of  different  foods,  424, 

426 
stimulated  by  clear  soups,  91 
Digestive  organs,  enfeoblement  due  to 

purely  vegetable  di:>t,  179 
Diphtheria  conveyed  by  milk,  117 
Disease,  alcohol  in,  362 

communicated  by  ]iathogcnic  bac- 
teria in  milk,  116, 117 
feeding  in,  principles  of,  479-548 
malt  liquors  in,  351,  370 
milk  as  food  in,  123,  129 
resistance  to,   on  vegetable  diet, 
180 
on  protein  diet,  175 
Dittman,  tannic  acid  in  tea,  319 
Diuretic,  milk  as,  129 

properties  possessed  by  koumiss, 
142 
Donders,     incomplete    absorption     of 

bran,  210 
Donkin,  use  of  milk  in  diabetes,  494 

value  of  milk  as  food  in  disease,  130 
Dorina  Nursery  Biscuits,  475 
Dough,  197,  198 

Dripping,  value  of,  as  food,  138 
Dropsy,  cardiac,  salt-free  diet  in,  557 
Dubhn,  diet  of  working-class  families 

in.  34 
Duck,  composition  of,  63 
Dujardin-Beaumetz,     composition     of 
wine,  375 
meat  and  beef  powders,  108 
Dukes,  Clement,  childhood  diet,  476 
division  of  meals  in  schools.  415 
results   from   deficiency   of   green 
vegetables  in  diet.  252 
Dulcin,  chemical  substitute  for  sugar. 

2S7 
Dunlop,  J.  C,  prison  diets  in  Scotland, 
34 


Duodenum,  passage  of  food  through, 

429 
Duplex  Boilerette,  407 
Dupre   on  constituents  of  wine,    377, 

378,  386 
Dutch  Butter.     See  Margarine 
Dysentery,  dietetic  treatment,  534 
Dyspepsia,     acid,    so-called     oxaluria, 
variety  of,  298 
atonic  or  flatulent,  dietetic  treat- 
ment, 531,  532 
functional,  529 

dietetic  treatment,  423,  529 
importance  of  pancreatic  di- 
gestion in,  429 
importance  of  use  of  invert  or 

diluted  sugar  in,  278 
varieties,   dietetic  treatment, 

530 
See  also  Flatulence,   Hjrperchlor- 
hydria 

Hastes,  Dr.,  tubercle  bacilli  in  milk,  117 
Ebstein's  diet  for  obesity,  507 
Economic  tests  of  value  of  food,  15 
value  of  arrowroot,  sago,  tapioca, 
247 
of  banana,  258 
of    condensed    milk,     small, 

465 
of  fish  diet,  84 
of  maize,  great.  226 
of  meat,  70 
of  potatoes,  242 
of  sugar,  281 
of  vegetable  foods,  181 
Eczema,  diabetic,  how  produced,  277 
dietetic  treatment,  547 
due  to  deficiency  of  green  vege- 
ables  in  diet,  252 
Edinburgh,   diet   of   labouring   classes 
as  estimated   by   standard 
dietaries,  34 
found  to  be  insufficient, 
56 
students  at,  dietary,  34 
Egg-albumin,  151 
Egg-shell,  composition,  151 
Egg-white  as   substitute  for  raw-beef 
juice,  102,  109 
composition,  151 

incapable  of  exciting  gastric  secre- 
tion, 418 
Eggs,  150-159 

absorption,  158 

and    milk,    supplement    to    vege- 
tarian diet,  176 
boiling  of,  398 
changes  in,  when  kept  and  when 

rotten,  156 
chemical  composition,  152-156 


INDEX 


593 


Eggs,  chemical  percentage  composition 
of  white  and  yolk  of, 
152 
same  in  eggs  with  dark  or 
with  white  shells,  155 
condensed,  158,  159 
digestibility,  157 
idiosyncrasy  in,  158 
nutritive  value,  158 
preparation  of,  as  infant  food,  ^72 
protein-producers,  176 
purin-free,  and  permissible  in  gout 

diet,  155 
substitutes  for,  159 
supplement  to  vegetarian  diet,  176 
See  also  Yolk  of  egg 
Ehrstrom,  cas"ein  enemata,  571 
Eichhorst,  casein  enemata,  571 
Elastin,  59 
Empirical  method  for  constructicju  of 

standard  dietaries,  26 
Emulsions,  composition  of,  569 
Endosperm  of  wheat,  igo,  191 
Enemata,  nutrient.    See  Rectal  feediuj; 
Energy  engendered  by  meat  diet,  174 
of  different  groups  of  food,  10 
potential,  amount  of  Calories  re- 
quired for,  35,  36 
amount   to   be   contained   in 
diet,  25 
property  of  nervous  system,  174 
sudden    and    sustained,    strength 
factors  severally  producing,  174, 

175 
supphed  by  protem,  175 
Energy  value  of  foods,  7 
Entire  Wheat  Bread,  Wheat  Bread  and 
Graham  Bread  compared  with,  212 
Epilepsy,  diet  in,  545 
Equilibrium,  nitrogenous,  21,  53 
Esbach,  oxahc  acid  in  food,  297 
Esquimaux,    consumption   of   blubber 

by,  explanation,  27,  50 
Ethers  in  wine,  378,  395 
Ethyl  alcohol.     See  Alcohol 
Ewald's  enema,  574 
Ewell's  analysis  of  commercial  cocoa, 

328 
Excreta.     See  Faeces 
Exercise,  effect  on  muscle-fibre,  59 
«influence  of,  on  digestion,  433 
Extractives  in  human  milk,  437 
in  meat,  61 

contain  no  nutritive  value,  61 
in  vegetable  food,  164 
in  wine,  379,  394 

presence  of,  constitutes  chief  value 
in  Liebig's  Extract,  93,  95 

Faeces,  chemical  composition,  431 
foetid,  production  of,  430,  431 


Faeces,  formation  and  composition  of, 

431 
influence  of  diet  on  water  in,  300 
nitrogen  in,  source  of,  170 
Fairchild's    Peptogenic    Milk    Powder, 

461 
Fallacies,  dietetic,  15 
Farina,    diastased,    or   English   arrow- 
root, 247,  468  Table 
Farola,  219 

Fat,  absorption  of,  10 
intestinal,  572 
abstinence  from,   and   linbility  to 

tuberculosis,  418 
amount  required  in  diet,  26 
and  protein,  compounds  of  cheese, 

147 

artificial  fat  foods,  568 

costliness  of,  16 

deficient  in  green  vegetables,  251 
in  pulses,  232 
in  rice,  229 

degree  of  concentration  possible, 
560 

digestion  of,  how  effected,  429 

effect  of  heat  on  food-fat,  397 

in  almonds,  370 

in  butter,  134,  570 

in  cereals,  188 

in  cheese,  147 

renders  its  digestion  difficult, 
150 

in  chocolate,  570 

in  cream,  133 

in  diabetic  diet.  485,  488   489,  491 

in  diet  of  infancy,  434 
in  phthisis,  513,  514 

in  meat,  59,  69 

in  rectal  feeding,  572 

in  subcutaneous  feeding,  578 

in  toffee,  570 

in  vegetable  foods,  164,  169,  171 
nutritive  value,  171 

incapable  of  exciting  gastric  secre- 
tion, 419 

interdiction  in  jaundice,  430 

large  article  of  diet  in  cold  climates, 

50 
of  body,  effect  of  sleep  on,  42 
of  milk.  III,  570 

of  cow's  milk,  452 

of  human  milk,  440.  446,  452 

variable  ingredient,  436 
reliable  gauge  of  quality,  114 
protein-sparer,  22 
.sources  of,  in  child's  diet,   174 
starvation,  effect  of,  431 
time  of  stay  in  stomach,  425 
Fattening  diet,  511-516 
in  convalescence,  513 

in  wasting  diseases,  513 

38 


594 


FOOD  AND  DIETETICS 


Fattening,   increase   of  carbohydrates 
and  fats  in,  512 
in  neurasthenia,  513,  515,  545 
in  rickets,  522 
Feer,    amount    of    milk    required    by 

infant  daily,  442 
I'~ermentation   of  bread,   process,    196, 
199 
of  koumiss,  141 
of  wine,  373.  374 
Fettmilch,  457 
Fever  diet,  480-4 88 

advantage  of  hberal  feeding,  477, 

481 
alcohol  in,  343,  346,  484-486 
beverages,  484 
fluid  diet,  482-486 
frequency  of  feeding,  484 
koumiss  in,  143 
liberal   supply   of   carbohydrates, 

482 
milk  in,  129,  483 
nutritive    constituents    necessary, 

481 
use  of  Mostelle  in,  257 
See    also    Rheumatic    fever,    Ty- 
phoid fever 
Fibrositis,  519 

Fick,  sugar  in  fever  diet,  483 
Figs,  259 

nutritive  value,  259 
Filtering  of  water,  306 
Finkler,  Dr.,  Tropon  first  prepared  by, 

562 
Fish,  78 

absorption,  82 

aphrodisiac  properties  of  fish  diet 

not  proved,  83 
chemical  composition,    78-80,   88, 

89 

cooking  of,  400 

digestibility,  81,  82 

economic  value,  16,  84 

'  fat,'  79,  82 

digestibility,  82 

iodine  in,  298 

lean,  79,  82 

digestibility,  82 

leprosy  caused  by  fish  diet,  84 

methods  and  effect  of  cooking,  400 

not  rich  in  phosphorus.  S;^ 

not  valuable  as  brain  food,  83 

nutritive  value,  83 

•  offal  '  of,  85 

preserved  v,  aste  matter,  79,  81,  84 

smoked,  82 
Flatulence    in    functional    dyspepsia, 
dietetic  modification  for,  528 

in  heart  failure,  dietetic  modifica- 
tions for,  539 

produced  by  certain  pulses,  231 


Flavour  of  fruits,  use  of,  256 

of  meat,  61 
Fleischer  on  exercise  after  meals,  433 
Flesh  of  animals  which  have  died  of 

disease  as  food,  70,  71 
Fletcher,  H.,  on  mastication,  412 
Flint,  insufficient  feeding  in  relation  to 

cold,  55 
Florador,  219 
Florence    and    Mairet,    food    required 

during  mental  labour,  41 
Flour,  193 

addition  of  malt-extract  to,  204 
of  various  substances  to  flour 
to  increase  nutritive  value 
of  bread,  215,  216 
adulteration  with  maize-flour,  224 
cookery  of,  196 

gluten    in,    alone    renders    bread- 
making  possible,  196 
'  self-raising,'  200 
'  standard,'  217 
varieties,  193 

See  also  '  Banana  flour.'  '  Frame 
Food  '  process,  '  Graham  '  flour. 
'  Households '  flour, '  Hovis '  flour 
Fluorine,  298 
Food-fruits,  256,  257 
Food-value  of  alcohol,  344,  345,  350 
of  cocoa,  335 
of  coffee,  332,  333,  334 
of  condensed  milk,  464 
of  human  milk,  445 
of  malt-extracts,  566,  567 
of  malt  liquors,  370 
of  tea,  332,  333,  334 
of  treacle  and  golden  syrup, 

567 
See  also  Nutritive  value 
Football  players,  value  of  sugar  in  diet 

of,  284 
Force,  220 

chemical  composition,  220 
Forced  feeding,  580 
Forster,   antiscorbutic  action  of  malt 
infusion,  521 
effect  of  cooking  on  water  in  foods, 

405 
salt  craving,  295 
Fothergill,  exaggerated  value  of  beef- 
tea,  106 
Fowl,  young,  composition  of,  63 
'  Frame  Food  '  process  for  retention  of 
bran  of  wheat,  195 
diet,  468  Table,  471 
France,  Central,  chestnut  as  article  of 

diet  among  peasants  of,  262 
Franklin,    Sir   John,    amount   of   food 

required  in  Arctic  regions,  49 
Fraser,  effect  of  tea,  coffee,  and  cocoa 
on  digestion,  329 


INDEX 


595 


French  and  Germans,  dietetic  capaci- 
ties compared,  52 
French  coffee,  324 
French  or  kidney  bean,  235 
Frogs'  legs  as  article  of  food,  88 
Fromm's  Extract,   chemical  composi- 
tion, 261 

commercial  preparation  from  nuts, 
260 
Frozen  meats,  70 

Fruit,  stewed,  laxative  action,  256 
Fruit-sugar,  or  laevulose,  274,  372 
Fruits,  252 

carbohydrates  in,  254,  493 

cellulose  in,  255 

chemical  composition.  253,  254 

cooking  of,  255,  256 

digestibiUty,  256 

dried,  259 

chemical  composition,  259 

flavour  and  odour,  255,  256 

laevulose  in,  254 

mineral  constituents,  255 

nutritive  value,  256,  257 

pentose  in,  255 

raw,  413 

sugar  in,  254 

use  of,  in  constipation,  536 
in  diabetes,  254,  493 

See  also  Food-fruits 
Frumenty,  192 
Frying  of  fish,  401 
Fuller,  phosphorus  in  food,  296 
Fungi,  263 

absorption  imperfect,  266,  267 

digestibility  of,  not  easy,  267 

edible  and  non-edible,  how  to  dis- 
tinguish, 263 
chemical  composition,  265 
nitrogen  in,  266 

nutritive  value  exaggerated,  267 

poisonous  properties,  263,  264 

See  also  Mushrooms,  Toadstools 
Fusel-oil.  354,  356,  363 
Fuster.  raw  meat  diet  and  alcohol  in 
tuberculosis,   556 

Gaertner's  Fettmilch,  457 
Galen,  difficulty  of  digestion  of  pulses, 
232 
therapeutic  value  of  milk,  130 
Gall-stones,  dietetic  treatment,  537 
Game,  digestibility,  68 

wild,  flesh  of,  superior  to  that  of 
home-fed,  61 
Gastralgia,  dietetic  treatment,  533 
Gastric  juice,  antiseptic  action  of,  427 
secretion  of,  416 

action  of  spices  on.  vari- 
able and  inconstant, 
285 


Gastric    juice,   secretion  ot,    loods   in- 
capable of  exciting,  418 
specific  kinds  for  partic- 
ular foods.  418 
stimulated  by  clear  soup, 
91.  419 
by  peptone  prepara- 
tion, 563 
powerfully    by    Lie- 
big's  Extract,  95, 
108,  418 
Gastric  ulcer,  524 

dietetic  treatment,  524-52G 

by  Lenhartz  method, 
525 
rest  of  stomach  in  arranging 
diet  for.  524 
Gastritis,  acute,  dietetic  treatment,  526 
chronic,  dietetic  treatment,  526 

avoidance  of  substances 
irritating  gastric  muc- 
ous membrane,  526 
Gautier,  solid  constituents  of  wine,  376 
Gavage,  580 

Gelatine,  chemical  basis  of  jellies,  76 
commercial,  78 
cost  of,  78 
digestibility  of,  77 
isinglass  purest  form  of,  76 
nutritive  value.  77 
powerful  protein-sparer,  22,  77 
produced  from  bones,  78 
yielded  by  collagen,  59 
Gelatinization  of  starches,  397 
Germ    breads,    216.     See    also    Hovis 
bread 
of  wheat,  190,  191,  192,  194 

removed  by  process  of  roller 

milling,  192 
retained    by    Smith's    patent 
('  Hovis  '  flour),  195,  204 
German    Army,    beneficial    results    on 
muscular  exertion  from  use  of  sugar, 
283 
Germans  and  French,  dietetic  capaci- 
ties compared,  52 
Gin,  359 
Ginger,  286 
Gingerade,  308 
Ginger  ale,  308 
Ginger-beer,  308 

stone,  308 
Giraud   on   incomplete    absorption    of 

bran,  210 
Glaxo,  infant-food,  468  Table,  469,  470 
Glendinning's  Wine,  389 
Glidine,  220,  561 

home-made    diabetic     bread    pre- 
pared from.  497 
Globenaris,  aerated  distilled  water,  307 
Glucose,  commercial,  276 


596 


FOOD  AND  DIETETICS 


Glucoses,  the,  270,  274 
Gluten  in  different  kinds  of  wheat,  193 
in   flour  alone  renders  bread-ma- 
king possible,  196 
Gluzinski,  digestibility  of  eggs,  157 
Glycerine  in  wine,  379 
Glycero-phosphoric  acid,  206 
Glycogen,  conversion  of  sugar  into  gly- 
cogen by  liver,  279,  2S0 
in  oyster,  86 
Glycosuria,  alimentary,  causes  of,  280 

gouty,  dietetic  treatment,  500 
Goat's  milk,  450 

Goitre,  exophthalmic,  and  heart  irrita- 
bility, vegetarian  or  lacto-vegetarian 
diet  in,  550 
Golden  syrup,  274,  567 
Goodfellow,  absorption  of  proteins  of 
wholemeal  bread,  211 
changes  which  bread  undergoes  on 

keeping,  205 
economic  value  of  bread,  218 
researches  on  digestibility  of  bread, 

213 
wholemeal  bread,  213 
Goodhart,  dietetics  of  gravel,  520 
Goose,  composition  of,  63 
Gout,  avoidance  of  tea  and  coffee  in, 

335 

avoidance  or  restriction  of  uric- 
acid-producing  foods  and  bever- 
ages in.  72,  73,  232,  516 

avoidance  or  restriction  of  meat 

in.  517 

beverages  in,  518 

chemical  substitutes  for  sugar  used 
in,  287 

chronic  articular,  Salisbury's  diet 
in,  553 

diet  in,  516.  518 

dietary  at  Carlsbad,  517 

influence  of  wine  on,  393,  394 
Gouty  glycosuria.     See  Glycosuria 
'  Graham  '  Bread  compared  with  white 

bread  and  entire  wheat,  212 
'  Graham  '  flour,  composition  of,  201 
Graham,  waste  in  bread-making,  199 
Gramalt,  567 
Granola,  219 
Granuto,  219 
Grape,  256 

juice  of,  372 
Grape-cure,  256 

in  abdominal  plethora,  257 

in  chronic  bronchial  catarrh,  257 
Grape-nuts,  220 

chemical  composition,  220 
Grape-sugar,  or  dextrose,  274,  372 
Grape-wines,  non-alcoholic,  390 
Gravel,  avoidance  of  rhubarb  in  cases 
of,  252 


Gravel,   dietetics,  519.     See  also  Uric 

acid  gravel 
Graves'    disease,     dietetic    treatment, 

546 
Greek  wines,  385,  395 
Green  on  tannic  acid  in  tea,  319 
'  Greening  '  of  oysters,  88 
Gregor,  K.,  fat  in  human  milk,  436 
Grinding    wheat    by    stone,     an    old 
method,  192 
bran  alone  removed  by  this  pro- 
cess, 192 
Groats,  221 

Gros,  rectal  feeding,  573 
Griinbaum,  O.,  enemata  of  ox-serum, 

576 
Griitzner,  reverse  peristalsis,  572 
Guinness's  Dublin  Stout,  368 
as  soporific,  370 

Haddock,  nutritive  value  same  as  that 

of  sole,  16,  84 
Haemoglobin,  digestibility  and  absorp- 
tion, 72,  73 
in  meat,  60 

iron  in  haemoglobin,   and  deriva- 
tives ill-absorbed,  72,  292 
Haig,  A.,  lacto-vegetarian  diet  (puriu- 

free  articles),  552 
Halliburton,    W.    D.,    F.R.S.,    digesti- 
bility and  absorption  of  haemoglobin, 
72,  73 
Hammarsten,  constituents  of  whey,  457 
Hammond,  food  value  of  alcohol,  346 

attempt  at  restricted  diet,  30 
Hare,  F.  E.,  system  of  diet  of,  552 

oxidation  of  proteins  under,  555 
Harley,  Vaughan,  personal  experiment 
on     assimilation     of  cane- 
sugar,  281 
experiments  with  sugar  as  a 
muscle-food,  283 
Hart,  digestion  of  casein,  120 
phosphorus  in  food,  296 
Haughton,     distinguishing    character- 
istics   of    sustained     strength     and 
sudden  energy,  174,  175 
Headaches,  dietetic  treatment,  546 
vegetarian    and    lacto-vegetarian 
diet  for,  550 
Health,   amount  of  food  required  in, 
20-34 
alcohol  in,  319,  391 
Heart,  stimulating  action  of  alcohol  on, 

340.  341 
Heart  disease,  dietetic  treatment,  538- 

540 

dry  diet  in,  539 
flatulence  in,  treatment,  539 
Heart-failure,  flatulence  accompanying, 
diet  for,  539 


INDEX 


597 


Heart-irritability,  abnormal,  of  nervous 
origin  and  in  exophthalmic  goitre, 
vegetarian  or  lacto-vegetarian   diet 
lor,  550 
Heart-substance  as  article  of  food,  72 
Heat  and  work  producers,  4 
Hercules  Patent  Meat-juice  Press,  99 
Herdmann  and  Boyce,  '  greening  '  of 

oysters,  87 
Herring,  nutritive  value  high,  84 
Heubner,  results  of  feeding  infants  with 

Soxhlet's  diluted  milk,  456 
Higgins,  H.,  mastication  and  digestion, 

412 
High  tea,  why  injurious,  331 
Hippocrates  on  bad  effects  of  under- 
feeding in  childhood,  56 
on  choice  of  food  for  patients,  480 
therapeutic  value  of  milk,  130 
Hirschfeld's  diet  for  obesity,  507 

on  body-weight  and  food  in  rela- 
tion to  season,  50 
Hock,  372,  381 

Hoesslein,  V.,  iron  in  food,  293 
Hoff's  Malt  Extract,  566,  567 
Holt,  schedule  for  feeding  infants,  444 
Hominy,  chemical  composition,  225 

preparation  of  maize,  225 
Homogenization  of  milk,  454 
Honey,  275 

chemical  composition,  275,  567 
Hony  White  Bread,  composition,  203 
Hoppe,  rectal  absorption  of  Sanatogen, 

571 

Hops,  365 

Horlick's  Malted  Milk.  468  Table,  469 
in  fever  diet,  483 

Horseflesh,  prejudice  against,  70 

Horse  -  serum,   subcutaneous    feeding 
with,  578 

Hospital  or  nursing  home,  treatment  of 
diabetes  should  begin  in,  501 

'  Households  '  Flour,  193 

'  Hovis  '  Bread,  203,  204,  216 

'  Hovis  '  Flour,  germ  retained  in,  195, 
204 

Hughes,  tannic  acid  in  tea,  319 

Humboldt  on  the  banana,  258 

Hundhausen,    introduction    of    Aleur- 
onat,  216 

Hungarian  wines,  381,  395 

Hunger,  416,  417 
definition,  416 
without  appetite,  417 

Hiippe  on  slow  cooking,  406 

Hydrochloric  acid,  chief  agent  of  pan- 
creatic secretion,  429 

Hyperchlorhydria,  dietetic  treatment, 

530 
in  functional   dyspepsia,   dietetic 

modifications  for,  531 


Hysteria,     vegetarian    or    lac  to-vege- 
tarian diet  in,  550 

Iceland  moss,  chemical  composition  of, 

269 
Ices,  avoidance  of,  428 
Idiosyncrasy  and  alcohol  consumption, 

349 
lUner  on  nursing  mothers'  diet,  440 
Illness,  composition  of  human  milk  in, 

439 
Immunity,  relation  of  alcohol  to,  351 
Inanition,  death  from,  point  when  it 

ensues,  54 
Indian  corn.     See  Maize 
Infant  diet,  in  acute  diarrhoea,  536 
carbohydrates  in,  435 
comparison  with  diet  of  adult 

446 
daily  amount  of  milk  required, 

442.  443 
importance  of  fat  in,  434 
in  infantile  diarrho       S36 
methods    of   prcpa  cow's 

milk,  453 
mineral  ingredients,  435 
pasteurization    and    steriliza- 
tion of  milk,  460 
physiological     requirements, 

434 
proprietary  infant  foods,  467- 

472 
regularity  in  feeding,  444 
schedule  of  amounts  required, 

442 
schedule  of  times  for  feeding, 

444 
substitutes  for  human  milk, 

448-472 
summary  of  rules  for  feeding 

infants,  471 
use  of  condensed  milk,  462-4G6 
of    partially    peptonized 

milk,  461 
of  water,  436 
of  whey,  457-459 
Infant  foods,  human  milk,  436-447 
milk,  cow's,  453 
human,  436-453 
proprietary : 

AUenbury     Foods,      468 

Table 
AUenbury  Malted  Food, 

468  Table 
Bananina,  258,  468  Table 
Benger's  Food,  468  Table, 

470,  4S3 
Carnrick's  Soluble  Food, 

j\(A  Table,   169 
Chapman's  W'liole  Wheat 
Flour,  468  Table,  471 


5Q« 


FOOD  AND  DIETETICS 


Infant  foods,  proprietary:  Cheltine  In- 
fants' Food,  468  Table 

Cheltine  Maltose  Food, 
468  Table,  494 

comparative   value,   470, 

471 
compared     with     dried 

human  milk,  470 
Coombs'     Malted     Food, 

468  Table 
Diastased     Farina,      468 

Table 
Frame-food     Diet,      468 

Table,  471 
Glaxo,  468  Table,  469 
Horlick's     Malted    Milk, 

468  Table,  469 
Laibose,  468  Table 
Manhu  Infant  Food,  46S 

Table,  469,  494 
MelUn's  Food,  468  Table, 

470 
milk,  human,  dried,  468 

Table 
milk   products   requiring 

water,  468  Table 
Milo    Food,    468    Table, 

469 
Moseley's      Food,       468 

Table,  470 
Neave's  Food,  468  Table, 

471 
milk  food,  468  Table 
Ridge's  Food,  468  Table, 

471 

Robinson's  Groats,  468 
Table,  471 

Robinson's  Patent  Bar- 
ley, 227,  472,  486  Table, 

471 

Savory  and  Moore's 
Food,  468  Table,  470 

Scott's  Oat  Flour,  468 
Table 

Theinhardt's  Soluble  In- 
fant Food,  468  Table 

transformed  starch  foods 
requiring     milk,      468 
Table 
Infants  absorb  milk  better  than  adults, 

digestibility  of  starch  by,  472 
intestinal    more    important    than 
gastric  digestion  in,  445 
Insomnia,  action  of  stout  on,  370 

nervous,  vegetarian  or  lacto-vege- 
tarian  diet  in,  550 
Intestinal  putrefaction  restrained   by 

koumiss,  142 
Intestine,  absorption  of  constituents  of 
human  milk  in,  445 


Intestine,  acclimatization  of  Bulgarian 
bacillus  in,  558 
antiseptic   properties   of   milk   in, 

126 
'  ballast,'  a  stimulus  to  peristalsis 

of,  13,  168,  169,  251,  536 
behaviour    of    human    milk    and 

cow's  milk  in,  453 
digestion  and  absorption  of  food, 
429-431 
in,  importance  in  infants,  443 
in,  of  vegetables,  165,  166 
(large),  formation  of  faeces  in,  431 
power  of  absorbing  food,  571- 
573 
presence  of  one  food  in,  affecting 

absorbability  of  other,  12 
restraint  of  destruction  of  proteins 

in,  13 
starch  in,  unfavourable  to  absorp- 
tion of  protein,  170 
water  absorbed  solely  by,  303 
Intestines,   diseases  of,   dietetic  treat- 
ment, 533-537 
Inulin  in  artichokes,  245 
Iodine,  298 

in  fish,  298 
in  thyroid  gland,  298 
Irish,  or  Carraigeen,  moss,  268 

chemical  composition,  268 
Irish  peasants,  potato-belly  of,  242 
Iron   in   haemoglobin   and   derivatives 
ill-absorbed,  72,  292 
in  milk,  in 
in  5'olk  of  egg,  154 
proportion  of,   in  different  foods, 
291-293 
in  relation  to  ancemia,  293 
sources  of,  288-290 
Isinglass,  purest  form  of  gelatin,  76 
Iso-lichenin  in  Iceland  moss,  269 
Italian  pastes,  218 

chemical  composition,  219 
Italian  wines,  381 

Jago  on  waste  in  bread-making,  199 
Jam,  276 

compared  with  butter,   137,   138, 

476 
proportion  of  cane-sugar  in,  276 
Japanese,  low  consumption  of  protein 

among,  173 
Jaundice,  dietetic  treatment,  538 
fat  forbidden  in,  430 
use  of  whey  in,  133 
Jaworski,  digestibility  of  eggs,  157 
Jellies,  76 
Jessen,  digestibility  of  beef  and  mutton 

compared,  67,  68 
Jessop,  exaggerated  value  of  beef-tea, 
107 


INDEX 


599 


Jessop,  exaggerated  value  of  Licbig's 

Extract,  94 
Johannis,  natural  mineral  water,  309 
Johnny-cakes,  224 

chemical  composition,  224 
Johnston,  banana  flour,  258 

losses  in  cooking,  404 

record  of  tradition  of  stimulating 
action  of  coffee,  332 
Junket,  114.  115 

avoidance  by  diabetics,  115,  496 

Kaisow  tea,  315 

Kanakas,  the,  method  of  slow-cooking, 

411 
Karrell,  value  of  milk  as  food  m  disease, 

130 
Keller,  phosphorus  in  food,  296 
Kemmerich,   analysis  of  Liebig's  Ex- 
tract, 92,  93 
Kephir,  139.     See  also  Koumiss 
chemical  composition,  141 
forbidden  in  diabetes,  496 
Kephir  grains,  139 

Kepler's  composition  of  malt-extract, 
566 
oil  and  malt,  569 
Kernel  of  wheat.     See  Endosperm 
Kidney  bean,  235 

Kidney  disease.     See  Renal  disease 
Kidney-substance   as   article   of   food, 
72 
avoidance  of,  in  gout,  72 
Kitchener,   Dr.,   effect  of  exercise  on 
muscle-fibre,  59 
non-belief  in  nutritive  qualities  of 
fungi,  267 
Koch,  analysis  of  peptones,  565 
Koeppe,    value     of     natural     mineral 

waters,  311 
Kola,  an  ingredient  of  Vi-Cocoa,  336 
Konig,  composition  of  potted  lobster 
86 
composition  of  potted  meats,  74 
efiects  of    cooking  on    meat,    64, 

65 
losses  in  cooking,  404 
losses  in  cooking  of  yolk  of  egg, 

154 
and   Bomer,    analysis   of  Liebig's 

Extract,  93 
Kops  Ale,  371 

Koumiss  and  kephir,  139,  140 
absorption,  142 
alcohol  in,  141 
chemical  composition,  141 
digestibility,  141 
fermentation,  139,  140 
forbidden  in  diabetes,  496 
general    therapeutic    applications, 

142.  143 


Koumiss,  nutritive  qualities,  142 

possesses  diuretic  properties,  142 
production  of  lactic  acid  in,   140. 

141 
restrains    intestinal    putrefaction, 
142 
Kozai,  Y.,  comparison  between  black 

and  green  tea,  317 
Kriieg,  subcutaneous  injection  of  oil, 

57« 
Krummacher,  protein  digestion,  415 
waste    of   proteins    in    body,    415 
notes 

Labourer,    outdoor,    thrives    on    vege- 
tarian  diet   better    than   sedentary 
worker,  t8o 
Labouring   classes,    diet   of,    suggested 
improvement  in,  56 
in  Dublin,  diet  of,  34 
in   Edinburgh,    diet   of,    esti- 
mated     by     standard 
dietaries,  34 
found  to  be  insufi&cient, 
56 
in   York,    diet  estimated   by 
standard  dietaries,  34, 

56 
found  to  be  insufficient, 
56 
Lactalbumin  in  milk,  no,  116 
Lactation,    variations  in  human  milk 

dependent  on  period  of,  437,  438 
Lactic  acid  in  milk,  115 

produced  by  sugar  fermentation, 

278.  279 
production   of,    in   koumiss,    140, 
141 
Lactose,  274 

least  liable  of  all  sugars  to  undergo 

fermentation,  279 
See  also  Milk-sugar 
Lacto  -  vegetarian     diet     (purin  -  free 
bodies),  549,  550 
therapeutic  uses  of,  550 
Laevulose,  or  fruit-sugar,  274,  372 
in  diabetes,  498 
in  fruits,  254 
Lancet  Commission  on  chemical  com- 
position of  baking-powders,  200 
Langworthy,  composition  of  caviare,  85 
composition  of  oysters,  86 

of  tinned  lobster,  86 
economic  value  of  fish,  84 
'  greening  '  of  oysters,  88 
'  La  Nu  Lofe,'  203 
La  Touche.  C.  D.,  diet  of  working-class 

families  in  Dublin,  34 
Lavoisier,  changes  of  food  in  body,  4 
'  Leaven,'  or  fermentation  of  bread  by 
yeast,  196,  197 


6oo 


FOOD  AND  DIETETICS 


Lecithin.  296 

proportion    relatively    greater    in 
human  than  in  cow's  milk,  451 
Legumin    561 

chief  protein  in  pulses    231 
Lehmann's  humanized  milk,  459 
Lemco.     See  Liebig's  Extract 
Lemco  wine,  389 
Lemonade,  308 

made  from  fresh  lemons,  beneficial 
action  in  scurvy,  521 
Lenhartz's  method  of  dietetic  treatment 

of  gastric  ulcer,  525 
Lentil,  235 

protein  in,  178 
Leprosy  due  to  fish  diet,  84 
Letheby,  barley  meal  as  food.  227 
Leube,  meat  solution,  103 

nutrient  enemata,  574 

relative  digestibility  of  food,  427 

subcutaneous  injection  of  grape- 
sugar,  578 
Leube-Rosenthal's  Meat  Solution,  524 
Lichenin  in  Iceland  m®ss,  269 
Lichens  as  food  269.     See  also  Iceland 

moss 
Liebig,  hock  as  beverage,  393 

muscle  food,  37 

stimulating  qualities  of  his  extract, 

94 
values  of  organic  constituents  of 
food,  2 
Liebig's  Extract,  61,  92,  95 

chemical  composition,  92,  93 
contains  practically  no   pro- 
tein, 92,  95 
gastric    secretion    powerfully 

excited  by,  95,  108,  418 
stimulating  qualities  doubtful, 

94.  95 
value  depends  on  extractives, 

Life  impossible  without  protein,  3 
'  Lights.'     See  Lung-substance 
Lime-juice,  beneficial  action  in  scurvy, 

521 
Lime-water,  dilution  of  milk  with,  to 

aid  digestibility,  120 
Lipanin,  569 
Lipton's  Fluid  Beef,  loi 
Liqueurs,  360 
Liquor  Carnis,  loi,  102 
Lithia  water,  307 
Liver,  cirrhosis  of,  143 

dietetic  treatment,  537,  557 
koumiss  useful  in,  143 
converts  sugar  into  glycogen,  279, 

280 
diseases  of,  dietetic  treatment,  537 
Liver-substance  as  article  of  food,  72 
avoidance  in  gout,  72,  510,  .511 


Loaf,  colour  and  composition  of,  201 
Lobisch,  effect  of  sleep  on  bodily  fat, 
42 
sleep  in  relation  to  amount  of  food, 
42 
Lobster  as  article  of  food,  85 
Luff,  A.  P.,  acids  in  wine,  378,  393 

value  of  somatose,  564 
Lung-substance  ('  lights  ')  as  article  of 

food,  73 
Lunin,    mineral   constituents   in   focd, 

290 
'  Lupa  '  Humanizer  for  use  in  modifi- 
cation of  milk,  455 

Macaroni,  218 
Mace,  286 

Macfadyen  on  reverse  peristalsis,  573 
Madeira,  378,  384 
Magnesia  water,  307 
Magnesium,  sources  of,  291 
Maine,  University  of,  experiments  on 
students  as  to  dietetic  value  of  milk, 
129 
Mairct    and    Florence,    food    required 

during  mental  labour,  41 
Maize,  223 

chemical  composition,  224 
economic  value  great.  226 
nutritive  value  high,  226 
See    also    Cerealine.    Corn    flakes. 
Cornflour,      Hominy,      Maizena, 
Oswego,  Popcorn,  Samp,  Sugar- 
corn 
Maize  flour  used  to  adulterate  wheat- 
flour,  224 
Maize  meal,  224 
Maizena,  225 

chemical  composition,  225 
Malcolm,    percentage    composition    of 

egg-yolk.  152 
Malt,  preparation  of,  365 
Malt-extracts.  566 

addition  to  flour,  204 
desiccated,  567 
See  also  Hoff's  Malt-extract 
Malt-infusion,      beneficial     action     in 

scurvy,  521 
Malt  liquors,  364-371 

action  on  digestion,  369 
ale  and  beer,  364-371 
composition  of,  368 
food  value  of,  374 
in  disease,  370 
porter  and  stout,  367-369 
Maltina  Brown  Bread,  composition,  203 
Maltina  White  Bread,  composition,  20  j 
Maltine  and  cod-Uver  oil,  569 

in  fever  diet,  487 
Malting  of  bread,  204 
Maltose,  271 


INDEX 


60 1 


Maltova,  567 

Malt  wllisk3^  355 

Malvern  water.   See  Sparkling  Malvern 

Maly,  food  and  nutritive  constituents, 

15 

Manhu  Bread,  composition,  203 

Infant  Food,  468  Table,  469,  494 
Maple-sugar,  273 

chemical  composition.  273 
Mare's  milk,  450 

chemical  composition,  141 
Margarine,  135 

chemical  composition,  136 
nutritive  value,  138 

nearly  equals  that  of  butter, 
136 
origin  of,  135 
Marggraf,  the  discoverer  of  beet-sugar, 

272 
Marmite,  extract  prepared  from  yeast, 

98 
Marsala,  385 

Mason's  Strong  Beef-tea,  chemical  com- 
position, 107 
Masson,  process  for  reducing  water  in 

vegetable  foods,  164 
Mastication  of  food,  importance,  412 
Mate.     See  Paraguay  "Tea 
Meals,  amount  at,  415 

arrangement  in  diabetes,  499 

in  obesity,  505,  506 
children's,  415 
frequency  of,  415 
hours  of,  415 
relaxation  after,  433 
Meat,  58 

acids  in,  60 

addition  to  bread,  215 

avoidance  at  tea  meal,  331 

or  restriction,  in  gout,  517 
chemical  composition,  61,  63 
consumption,     restricted     among 

lower  classes,  70 
cooking  of,  397-400 

effect,  64 
diet,  appetizing  qualities  of,  181 
energy  engendered  by,  174 
digestibility,  67 

and  absorption,  65,  68 
idiosyncrasy  in,  68 
retarded  by  cooking,  67 
digestion,  66 
diseased,   harmless  when  cooked, 

71 
economy  of,  70 
effects  of  fattening  on,  62 
expensive  as  food,  70,  474 
fat  in,  59,  69 
fibre,     meat-extract    preparations 

containing,  97 
flavour,  60,  61 


Meat,   flavouring  constituents,  chiefly 
contained  in  soup,  90 
frozen,  70 
haemoglobin  in,  60 
increased     amount     in     diet     of 

phthisis  recommended,  514 
lean,    exclusive    diet    of,    causing 

foetid  stools,  430,  431 
method  of  cooking,   in   Salisbury 

cure,  67 
methods  and  effect  of  cooking,  397- 

400 
mineral  substances  in   61 
mixture  with  flour,  215 
muscle  fibre  in,  60 
myosin  in,  60 
not  a  perfect  food,  69 
nutritive  value,  63 
physical  structure  of,  58 
potted,  74 
proteins,  68 
rabbits,  and  other  small  animals, 

expensive  forms  of,  71 
raw  or  underdone,  easily  digested, 

67 
recommended  in  phthisis,  514 
waste  matters,  62 
water  in,  62 

loss  of,  due  to  cooking,  64 
Meat-extractives,  61,  95 

most    powerful    excitants    of 

gastric  secretion,  418 
not  a  food,  94 

principally  broken  down  pro- 
tein, 94 
stimulate  flow  of  gastric  juice, 

108 
See    also    Beef-Extract,    Lie- 
big's  Extract 
Meat -juice,  fresh,   beneficial  action  in 

scurvy,  522 
Meat-juice  press  (Hercules  Patent),  99 
Meat-powders,  107,  109 
Medicated  wines,  388 
Meigs's  cream  mixture  for  infants,  455 
Mellin's  Food,  468  Table,  470 
Men,  relative  values  for  food  require- 
ments at  different  ages,  45 
Mendel,  wine  and  digestion,  390 

and     Chittenden,    absorption     of 
alcohol  by  the  stomach,  339 
analysis  of  Burton  Pale  Ale, 
368 
of     Guinness's     Dublin 
Stout,  368 
Mental  work,  food  required  for,  41 
Metabolism,  4 

disorders  of  diet  in,  488 
influence  of  alcohol  on,  344-349 
of  salt  on,  294 
of  water  on,  304 


6o2 


FOOD  AND  DIETETICS 


MetchnikoflF,  sour-milk  treatment,  558 
Micro-organisms  in  milk,  117 
Midelton,    egg-preparation    as    infant 

food,  472 
Milk,  1 10-13 1 

absorption,  124 

in  intestine,  126 
action  of  rennet  on,  in  formation  of 

cheese,  146 
aeration,  121 
and  eggs,  supplement  to  vegetarian 

diet,  176 
and  oatmeal,  former  staple  diet  of 

Scottish  peasants,  174 
and    soda,    why    more    digestible 

than  plain  milk,  122 
antiseptic  properties  in  intestine, 

126 
as  diuretic,  129 
as  protein-producer,  177 
boiled,  122,  126 

and  unboiled,  comparative  ab- 
sorption, 125 
avoidance  in  infantile  scurvy, 
522 
boiling  of,  effect  on  composition, 

116 
calcium  in.  290 
casein  in.  no,  115,  451 
characteristics  in  different  animals, 

448-452 
chemical  composition,  no,  127 
citric  acid  in.  112 
clotting  of.  114,  115,  120 

in  stomach,  1 19-120,  122,  453 
coagulation,  114 

condensed.     See  Condensed  milk 
curdling  distinguished  from  clot- 
ting, 115 
desiccated,  119,  467 
analysis  of,  119 
diabetic,  sugar-free,  498,  499 
digestibiUty,  1 19-124 

addition  of  citrate  of  soda  to 

aid,  121 
dilution   with    lime-water    or 

barley-water  to  aid,  121 
methods   of  improving,    120, 

122 
relative,    of   boiled    and    un- 
boiled, 121,  124 
dilution,  121 

with  alkalies,  121,  122 
exercises  antiseptic  action  oa  in- 
testines, 126 
fat  in.  III,  570 

reliable  gauge  of  quality,  114 
feeding  by  bottle    avciage  meals, 

..     443 
-    foods  derived  from,  132-145 
foreign  matter  in,  117 


Milk,  homogeiiization  of,  454 

human,  absorption  of  constituents 
in  intestine,  445 
amountrequired  daily, 442, 443 
chemical  differences  between 

human  and  cow's.  450 
choice  of  wet  nurse,  439 
clotting  in  stomach,   density 

slight,  453 
compared  with  ass's  milk,  4-19 
composition,  463,  473 

independent    of    outside 
influences,  439 
diet  of,  pure,  130 

symptoms  under.  131 
digestibility,  445 

of  human  and  cow's  milk 
compared,  452 
extractives  in,  437 
fat  in,  440,  446,  452 

variable  ingredient,  436 
influence  of  illness  on,  439 
of   mother's   and   child's 

individuality,  433 
of  mother's  diet  on,  440. 
441 
lecithin   in,    proportion   rela- 
tively greater  than  in  cow's 
milk,  451 
mineral    salts    in,    compared 

with  those  in  cow's,  452 
nutritive  value,  445-447 
phosphorus  in,  452 
substitutes:  condensed  milk, 
462-466 
Fairchild's       Peptogenic 

Milk-powder,  461 
other  animals'  milk,  448- 

460 
partially  peptonized  milk, 

461 
preparations     of     cow's 

milk,  453-460 
proprietary  infant  foods, 
467-472 
variations  dependent  on  indi- 
vidual    differences     in 
mother  or  child,  439 
dependent  on  period  of 

suckling,  437-439 
induced  by  frequent  suck- 
ling. 441 
humanized,  456-460 

analysis  of  preparation.  456 
chemically  impossible,  452 
intestinal  antiseptic,  431 
iron  in,  in 

lactalbumin  in,  no,  116 
lactic  acid  in,  115.     See  also  Bul- 
garian   bacillus.    Milk,    soured, 
Sour-milk  treatment 


INDEX 


603 


233 


Rliik,  micro-organisms  in,  117 
causing  disease,  117 
mineral  matters  in,  1 1 1 
mixture  with  pea-soup 
not  a  fluid  food,  114 
not  a  perfect  food,  127 
nutritive  value,  126 
pasteurization,  118,  460 
pathogenic  bacteria  in    11 6-1 18 
permanent  preservation   118,119 
proteins  of,  no,  128,  451 
separated,  in 

sterilization,  116,  118,  126.  460 
avoidance  in  infantile  scurvy, 
522 
'  sterilized,'    absorbed   as   well   as 

ordinary  boiled  milk,  126 
soured,  143 
sugar  or  lactose  in,  no 

carbohydrate    constituent    of 
milk,  no 
time  of  duration  in  stomach,  122 
transmissionof  disease  by,  116,  117 
use  in  acute  renal  disease,  541 
in  diabetes,  494 
in  fevers,  129,  483 
in  enemata,  574 
in  subacute  nephritis,  542 
value  as  food  in  disease,  123,  129, 

130 
water  in,  112 

See  also  Butter-milk,  Cow's  milk, 
Lacto-vegetarian     diet.     Skim- 
milk 
Milk-powders,  peptogenic,  461 
Milk-products,  carbohydrates  in,  493 
Milk-sugar,  568 

dilution  of  milk  mth, 
in  fever  diet,  483 
Millet,  229 

Indian,  229 

chemical  composition, 
Milling  wheat  by  roller,  192 

germ  of  wheat  removed 
[92 
Mill-products,  American,   £94 
chemical  composition, 
of  wheat,  194 
Milo  Food,  468  Table,  469 
Milt  as  article  of  diet,  85 
Mineral  constituents  of  food, 
daily    amount 

288.  289 
function      in 

body,  289 
in  supplying 
288,  289 
of  food,  in  organic  or  in- 
organic    combination, 

289,  290 
substances  required.  288 


456 


229 


bv, 


-95 


5-299 
required, 

Duilding 


?nergy. 


Mineral  mtitters  in  bread,  210 
in  ctrcals,  188 
in  child's  diet,  476 
in  cow's  milk,  452 
in  diet  of  infancy,  435 
in  fruits,  255 
in  meat,  61 
in  milk,  in 

in  vegetable  foods,  165,  250 
in  wholemeal  bread,  214 
Mineral  salts  in  human  and  cow's  milk 

compared,  452 
Mineral  waters,  artificial.     See  Aerated 
waters 
natural,  309,  310 
Adonis,  310 
ApoUinaris,  309 
Contrexeville.  310 
Johannis,  309 
Perrier,  309 
Rosbach,  309 
St.  Galmier,  310 
Seltzer,  310 
Sinaro,  310 

Sparkling  Malvern,  310 
Vichy,  310 

and  artificial   compared, 
311.  312 
uses  of,  310 

when  to  be  avoided,  310 
Miol,  569 
Mixed  diet,  necessity  for,  30 

feeders,  problem  of  diet  solved  by, 
176 
Mock-turtle  soup,  88 
Moeller,  incomplete  absorption  of  bran, 
210 
merits    of    white    and    v/holemeal 
bread,  211 
Molasses,  274 

Moleschott    on    ratio    of    protein    to 
carbohydrate  and  fat  in  childhood 
diet,  473 
Moning  tea,  315 

Montgomerie's     process     for     making 
'  Bermaline  bread,'  204 
rusks.  475 
Monti  on  use,  of  whey  for  infants,  458 

choice  of  wet  nurse,  439 
Moor  on  nutritive  value  of  condensed 
milk,  463 
and  Pearmain,  variability  in  com- 
position of  milk,   ti3 
Moore-Ede.   Dr.   (Dean  of  Worcester), 

apparatus  for  cheap  cooking.  408 
Moral  degeneration  from  underfeeding, 

57 
Morris-Manges',  Dr.,  typhoid  fever  diet, 

487 
Morris,   Sir  M.,   dietetic  treatment  of 
skin  diseases,  548 


6o4 


FOOD  AND  DIETETICS 


Moseley's  Food,  468  Table.  469 
Mosquera  Beef -meal,  107 

and  sanose,  540 
Mosso,    experiments   with   sugar   as   a 

muscle-food,  282 
Mostelle,  257 

use  in  fevers,  257 
Mother's    diet,    influence    on    human 

milk,  440,  446,  447 
Mountaineering,     value    of    sugar    as 

muscle-food  in,  284 
Mouth,  digestion  in,  412 
Muggia,    subcutaneous   administration 

of  yolk  of  egg,  579 
Mulder,  action  of  wine  in  health,  391 
Miiller,      subcutaneous     injection      of 

grape-sugar,  577 
Munk,    fat-forming    power    of    foods, 

512 
Murchison,  discussion  on  alcohol,  351 
Murphy,  C.  J.,  value  of  maize  as  food, 

226 
Murray,  use  of  spirits  in  disease,  362 
Muscle-fibre,  effect  of  exercise  on,  59 

in  meat,  60 
Muscle,  nutritive  requirements,  43 

strength  a  property  of,  174 
Muscle-food,  35-38 

alcohol  as,  345 
sugar  as,  280,  284 
Muscular  work,  influence  on  diet,  37 
Mush,  224 
Mushrooms,  263-268 
Mussels  as  food,  88 
Mustard,  285 
Mutton,  digestibility,  67 
Mutton-fat,  irritating  effect  on  stom- 
ach, 67 
Myosin,  60 

causes  rigor  mortis,  60 

Nationalities,  different,  dietetic  capaci- 
ties compared,  52 
Neave's  Food.  468  Table.  471 
Nencki,  reverse  peristalsis,  573 
Nephritis,    accompanied    by   constipa- 
tion, use  of  whey  in,  133 
acute,  541 

use  of  milk  in,  541 
avoidance  of  spices  in,  285 
chronic,  diet  in,  543,  544 

parenchymatous,  salt-free  diet 

in,  556 
use  of  lluids  in,  544 
subacute,  diet  in,  542 

average     daily     secretion     of 
albumin  in,  under  different 
diets,  542 
use  of  white  meats  in,  542 
Nervous  energy,  large  expenditure  in 
digestion  of  bulky  diet,  180 


Nervous  system,    diseases  of,    dietetic 
means    of    slight    value    in 
treatment,  545 
energy  a  property  of,  174 
influence  in  regulating  tissue 
waste,  51 
Nestle's  Milk,  465 

in  fever  diet,  483 
Neuralgia,  idiopathic  and  gouty,  vege- 
tarian  or   lacto-vegetarian   diet   in, 
515.  550 
Neurasthenia,  complicating  atonic  dys- 
pepsia. Weir  Mitchell  treatment 
in, 533 
fattening  diet  recommended  for, 

515.  545 
vegetarian  or  lacto-vegetarian  diet 

in,  550 
zomotherapy  in,  556 
Nevill's  Bread,  composition,  203 

Wheatmeal     Bread     composition, 
203 
Nitrates,  loss  of,  to  soil,  183 
Nitrogen,  absorption  diminished  during 
mental  work,  41 
abundant  in  pulses,  231 
amount  required  in  food,  21 
analysis     by     Kjeldahl     process, 

204 
as  source  of  muscle  energy,  37 
desirability  of  fixing  free  nitrogen 

in  air,  183 
food  cycle,  182 
in  edible  fungi,  266 
in  faeces,  source  of,  170 
insufficient     supply     not     incom- 
patible with  obesity,  54 
Nitrogenous  equilibrium,  21,  53 
substances  in  cow's  milk,  451 
in  vegetable  foods,  163 
Non-alcoholic  beers,  371 

grape  wines,  390 
Norwegian  Self-acting  Cooking  Appar- 
atus, 407 
Nuclein,  296 
Nucleins  of  food,  sources  of  exogenous 

uric  acid.  516 
Nucoline,    commercial   preparation   oi 

nuts,  260 
Nursing  home  or  hospital,  treatment  of 

diabetes  should  begin  in,  501 
Nurso  Rusks,  475 
Nut  butter,  commercial  preparation  of 

nuts,  260 
Nutmeal,    commercial    preparation   of 

nuts.  260 
Nutmeg,  286 
Nutricia,   modification  of  cow's  milk, 

459 
Nutrient  enemata.     See  Rectal  feeding 
suppositories,  576 


INDEX 


605 


Nutrition     function   of,    regulated   by 
central  nervous  system,  51 
impaired,  use  of  koumiss  in  cases 

Nutritive  constituents  of  food,  2 

amounts  required  daily, 
28 
Nutritive  value  of  almonds,  262 

of   arrowroot,    sago,    tapioca, 

247 
of  banana  flour,  258 
of  beef-tea  exaggerated,  106 
of  bread,  215-216 
of  casein  preparations,  144 
of  cheese,  149 
of  cocoa-nuts,  261 
of  eggs,  158 

of  fat  in  vegetable  foods,  171 
of  figs,  259 
offish.  83 
of  fruits,  256,  257 
of  fungi  exaggerated,  267 
of  gelatin,  77 

of  green  vegetables,  low,  251 
of  haddock,  16,  84 
of  herring,  84 
of  maize,  high,  226 
of  meat,  68 
of  milk,  126 

condensed,  465 
human,  445-447 
of  nuts,  261 
of  oats,  220 

of  oysters  diminished  by  fat- 
tening, 88 
not  high,  87 
of  potatoes,  239,  240 
of  pulses  high,  233 
of  starch,  171 
of  sugar,  171,  281 
of  turnip,  not  high.  244 
of  vegetable  foods,  171 
Nutrose,  peanut  an  ingreJient  of,  236 
Nuts,  259 

absorbability,  261 

chemical  composition,  259,  260,  262 

commercial  preparations,  260.   See 

also  under  various  names 
digestibility,  260 
malted,  260 

chemical  composition,  261 
nutritive  value,  261 
substitutes    for    butter    prepared 
from,  260 
Nuttolene,  commercial  preparation  of 

nuts,    20  3 

Nuttose,    commercial    preparation    of 
nuts,  260 

Oarsmen,   training  of,   value  of  sugar 
diet  in,  2S3 


Oatmeal,  174,  221 

and  milk,    former   staple   diet   of 

Scottish  peasants,  174 
avoidance  in  gout,  221,  551 
purin   bodies    (uric   acid   formers) 

contained  in,  221 
unfitted  for  bread-making,  222 
value  in  rickets,  523 
Oats,  220 

absorbability,  223 

most  nutritious  of  all  cereals,  220, 

223 
preparations  of,  chemical  composi- 
tion, 222 
rolling  of,  221 

See  also  Avenine,  Berina,  (Mont- 
gomerie's),  '  Carr's  Oaten  ' 
'  Creamota,'  '  Plasmon  Oat- 
meal,' '  Provost  Oats,'  '  Quaker 
Oats,' '  Veda  Oatmeal,"  '  Waver- 
ley  Oats  ' 
Obesity  aggravated  in  women  of  lux- 
urious life,  48 
not  incompatible  with  insufficient 

nitrogenous  nutrition,  54 
diet,  502-512 

alcohol  in,  370,  371,  506 
arrangement  of  meals,  509 
Banting  diet,  504 
beverages,  370,  371,  511 
chemical  substitutes  for  sugar 

used  in,  287 
dietaries,  504,  509 

relative  value  of,  508 
reduction    of     Calories,    503, 

504 
of  food,  503,  504 
of  fluid,  509,  510 
starvation       method       needs 

caution,  508 
vegetarian     and     lacto-vege- 
tarian,  550 
Oenanthine,  379 
Oertel's  diet  for  obesity,  506 
Offal  as  food,  71 

comparative  absorption,  74 
composition  of,  71 
nutritive  value  of,  72 
of  fish.     See  Caviare,  Milt,  Roc 
Ogata,  effect  of  tea  on  digestion.  330 
experiments     on    digestibility     oi 

sugar,  278 
influence  of  salt  on  digestion,  294 
Oil,  subcutaneous  injection,  578 
Old  age,  dietetic  requirements,  46 

temperance  in,  46 
Oleomargarine.     See  Margarine 
Olive  oil,  subcutaneous  injection   578 
Onions,  245 

avoidance  in  gout,  551 
rich  in  cellulose,  245 


6o6 


FOOD  AND  DIETETICS 


Onions,    viric  acid-forming  bodies    in, 

252.  551 
valuable  in  constipation,  254 
Oolong  tea,  316 

Ophthalmia,  epidemic,  and  underfeed- 
ing, 55 
Opmus  Bread,  composition,  203 
Orangeade,  308 
Osmazone,    production   on   surface   of 

roast  meat,  399 
Osteo-arthritis,  519 
Oswego,  preparation  of  maize,  225 
Ovalbumin,  151 
Ovaltine,  336 

Oven  for  cheap  cooking,  408 
Over-feeding,  52 

injurious  efiect  of,  53 
Ovomucin,  151 
Ovomucoid,  151 

Oxalic  acid,  foods  rich  in,  avoidance  in 
oxaluria,  521 
in  rhubarb,  252 
in  various  foods,  297 
source  of,  297 
Oxaluria,   dietetic  treatment,   521 

so-called,    variety    of    acid    dys- 
pepsia, 29S 
Ox-serum,  rectal  enemata  of,  576,  577 
Oyster  as  article  of  food,  86 

digestibility  easy  when  raw,  87 
fattening      diminishes      nutritive 

value,  88 
glycogen  in,  86 
'  greening  '  of,  87 
nutritive  value  not  high,  87 
transmission  of  typhoid  fever  by, 

87 
methods  of  avoidance,  87 
unsuitabilit}'^  in  diabetes,  86,  87 

Pabst,  use  of  white  meats  in  nephritis, 

542 
Paget,  Sir  J.,  discussion  on  alcohol,  351 
Paget's  Perfected  Milk  Food,  456 
Pancreas-substance  as  food,  value  of, 

73 
Pancreatic  digestion,  reserve  power  of, 
429,  430 
emulsion,  569 

juice,  digestion  of  fat  by,  429 
secretion  of,  stimulants,  429 
Paracasein,  120 

hydrochloride,  120 
Paraguay  tea,  336 
Paris,  use  of  horseflesh  as  human  food 

in,  70 
Parkes,  consumption  of  alcohol,  348 
and  WoUowicz,  eifects  of  alcohol 
on  the  circulation,  341 
"Parkinson    alcohol  and  immunity,  351 
Parsnips,  245 


Pasteurization  of  milk,  118,  460 

of  wine,  377 
Paton,  Noel,  diet  of  labouring  classes 

in  Edinburgh,  34 
Pavy,   F.  W.,   F.R.S.,   digestibility  of 

fish,  82 
Pawlow,  I.  P.,  digestibility  of  milk,  123 
excitants  of  appetite,  416 
experiments   on   action  of   condi- 
ments and  spices,  285 
meat  -  extracts  and  gastric  secre- 
tion, 95 
salivary  digestion,  413 
secretion  of  gastric  juice,  416,  417. 
418 
Payen    on    composition    of    parts    of 

lobster  and  crab,  85 
Peanut,  236 

diabetic  food,  236 
'  Nutrose  '  largely  compounded  of, 
236 
Pearmain  on  value  of  condensed  nuilk. 

463 
and  Moor,  variability  in  composi- 
tion of  milk,  113 
Pea-soup,  233 

mixture  with  milk,  233 
Peas,  garden,  235 
Peasmeal,  mixture  with  flour,  215 
Pectins,  163 
Pectose  in  turnips,  244 

in  \^cgctable  foods,  163 
Pegnin,  455 
Pekoe  tea,  314 
Pellagra,  19 
Pemmican,  107,  561 
Pentose  in  fruits,  255 
Pentosuria,  production  of,  280 
Penzoldt,  digestibility  of  eggs,  157 
digestibility  of  fish,  82 
relative  digestibility  of  foods,  424- 

426 
time  of  appearance  of  free  acid  in 
stomach,  420 
Pepper,  black,  285 

white,  285 
Pepsin  wines,  338 
Peptogenic  milk-powder,  461 
Peptones,  562-566 

chemical  composition,  565 
diarrhoea  caused  by,  563 
incapable  of  exciting  gastric  secre- 
tions, 418 
influence  on  digestion,  562 

on  secretion  of  gastric  juice 
and  on  appetite,  563 
Peptonized  food,  home-made,  366 
Peptonoids.    See  Carnrick's  Peptonoids 
Pereira,   non-belief  in  nutritive  quali- 
ties of  fungi,  267 
potatoes  as  food,  241 


INDEX 


607 


Pereira,    salivary    digestion   of   moist 

foods,  413 
Peristalsis  of  intestine,   stimulus  sup- 
plied by  ballast,   13,    168,   169, 

251 
of  intestine,  reverse,  573 
of  stomach,  338,  417 
Periwinkles  as  food,  88 
Perrier,  natural  mineral  water,  309 
Perry,  387 
Personal     peculiarity,     influence     on 

amount  of  food,  51 
Petroleum,  non-absorbability  of,  16 
Phosphates,  295,  296 
Phospho-carnic  acid,  296 
Phosphoric  acid,  absorption  diminished 
during  mental  work,  41 
absorption  of,   how  lessened. 

430 
percentage  in  fresh  foods,  295 
Phosphorus  contained  in  casein,  144 
fish  not  rich  in,  83 
function  and  sources,  295,  296 
in  food,  295 
in  human  milk,  452 
in  yolk  of  egg.  154 
not  necessary  as  brain  food,  41 
percentage  in  fresh  foods.  295 
Phthisis,  increased  supply  of  protein  in 
diet  for,  514 
fat  in  diet  for,  513,  514 
koumiss  in  diet  for,  142,  143 
meat  diet  for,  514 
Physical  tests  of  value  of  food,  4 
Physiological  effects  of  alcohol,  337-349 
method  for  construction  of  stan- 
dard of  dietaries,  25 
requirements  in  infant's  diet,  434 
tests  of  value  of  food,  8 
Phytin,  296 
Plantose,  561,  562 
Plants  synthetical  feeders,  184 
Plasmon,  addition  to  milk  in  fever  diet, 
483,  487 
casein  preparation,  143,  144,  561 
home-made    diabetic  .bread    pre- 
pared from,  497 
nutritive  value,  335 
with  lacto-vegetarian  diet,  511 
Plasmon  Chocolate,  328 
Plasmon  Cocoa,  335 
Plasmon  Diabetic  Biscuits,  497 
Plasmon  Oatmeal,  222 
Plasmon  Tea,  331 

'  detannation  '  of  infusion  through 
casein  in,  331 
Plastering  of  wine.  383 
Playfair  on  standard  dietaries,  33 

standards  of  number  of  Calories  to 
be  supplied  for  work  of  different 
degrees  of  severity,  36 


Pliny,  plastering  of  wine  mentioned  by, 

383 
Plombieres,    method   of   treatment   of 

muco-membranous  colitis  at,  534 
Poisonous  properties  of  fungi,  263 
Pone,  preparation  of  maize,  224 
Pop-corn,  chemical  composition,  225 

variety  of  maize,  225 
Popoff  on  digestibility  of  fish,  81 

on  digestion  of  meat,  66 
Porcherine,     chemical    substitute    for 

sugar,  287 
Pork  digestibility,  68 
Porridge,  222 

absorbability  of,  223 
and  milk  meal,  superior  to  tea  and 
bread  and  butter  meal,  223 
Port,  373,  384 

nutrient,  389 
Porter,  367 

PostnikoS,  nutritive  qualities  of  kou- 
miss, 142 
Potash  in  vegetable  foods,  165 

bicarbonate  of,  combination  with 
casein   of    cheese,    to    promote 
digestibility,  149 
salts  of,  depressant  effect  on  pulse 
not  exercised  by,  94 
in  potatoes,  239 
Potash  water,  307 
Potato-belly  of  Irish  peasants,  242 
Potatoes,  237 

absorbability,  16,  239 

avoidance  in  dilatation  of  stomach, 

239  . 
beneficial  action  in  scurvy,  236 
bulkiness  of,  242 
chemical  composition,  238,  241 
asparagin  in,  242 
richness  in  starch,  239 
cooking  of,  239,  240,  402,  403 
digestibility,  241,  242 
economic  value,  242 
nutritive  value,  239,  240 
salts  of  potash  in,  239 
See  also  Sweet  potato.  Yam 
Potted  meat,  74 
Poultry,  composition  of,  63 
Pozziale,     incomplete     absorption     of 

bran,  210 
Prausnitz,  absorption  of  milk,  125 

composition  of  faeces,  431 
Prautner  and  Stowasser,   experiments 

with  sugar  as  a  muscle  food,  283 
Predigested  foods,  562-566 
Priestley,  Joseph,  inventor  of  artificial 

aerated  water,  306 
Prison  diets,  data  as  to  absorption  of 
protein  derived  from,  170 
in  Scotland,  34 
Prolacto  Bread  in  diabetes,  497 


6o8 


FOOD  AND  DIETETICS 


Proof  spirit,  353 

Proprietary  infant  foods.     See  Infant 

foods 
Protein,  absorption  of,  10,  12 

by  large  intestine,  570 
defective,  in  bread,  209 
in  wholemeal  bread,  211 
amount  required  daily,  20,  176 
in  diet  for  training,  38,  39 
in  mental  strain,  39 
in  muscular  work,  44 
and   fat   essential    compounds    of 

cheese,  147 
broken-down,      meat     extractives 

principally  consist  of,  94 
bulk  and  weight  of  foods  yielding 

same  quantity,  177,  178 
butter-milk  cheap  source  of,  138 
coagulable,  in  beef- juices,  loi,  loS 
constant  supply  of,  necessary,  175. 

409 
deficient  in  rice,  229 
degree  of  concentration  possible, 

536 

diet,  exclusive.  See  Salisbury 
cure 

effect  of  heat  on,  396,  404 

foods,  artificial,  561-566 

high  percentage  in  casein  prepara- 
tions, 145 

in  bread,   methods  of  increasing, 

215  . 
in  casein,  145 
in  cereals,  187 
in  cheese,  147 
in  diabetes  diet,  491 
in  lentils,  178 
in  Liebig's  Extract,  amount  very 

slight,  93,  95.  96 
in  meat,  68 
in  milk,  no,  128,  451 
in  pulses,  231 
in  rectal  feeding,  571 
in  subcutaneous  feeding,  577 
in  vegetable  foods,  deficiency  of, 

172.  185 
difficult  to  absorb,    169, 

170.  173 
increase  of,  in  diet  for  muscular 
work,  37,  41 
in  diet  of  phthisis,  514 
increases  power   of   resisting   dis- 
ease, 175 
insoluble,  96 

insufficient,  leads  to  imperfect  tis- 
sue repair,  54 
lack  of,  in  food,  injuriousness  of, 

54 
life  impossible  without,  3 
minimum  of,  in  purely  vegetable 

diet,  185 


Protein,    minimum   amount    required 
for     healthy    maintenance 
of  life,  173,  176 
consumption,  173 
necessity  in  diet  of  growing  chil- 
dren, 175 
preponderance  in  animal  food,  172 
producers  of,  eggs  and  milk  as,  176 
ratio  of,  to  carbohydrate  and  fat  in 

child's  diet,  474 
relative     absorption     in     various 

foods,  169 
relative  cost  per  pound  in  different 

forms,  181 
skim-milk  cheap  source  of,  128 
sources  of,  in  child's  diet,  475 
sparers,  23,  53,  346 
gelatin  as.  77 
sugar  as,  281,  282 
stimulating  effects  on  cells,  69 
supplies  energy,   174 
vegetable,  163,  171 
Proteins,  destruction  by  putrefaction, 
430 
oxidation   under   purin-free    diet. 
Hare's    system    and    Salisbury 
cure,  555 
restraint  of  destruction  in  intes- 
tine, 13 
time  of  stay  in  stomach,  425 
waste  of,  in  body,  414,  415 
Protene,  144 

diabetic  bread,  497 

flour,  preparation  of  casein,   143, 

561 
home-made    diabetic   bread,    pre- 
pared from,  497 
Protoplasm  poisoned  by  alcohol,   344, 

345 
Proust,    first    to    recognize    refreshing 

properties  of  extract  of  meat,  95 
Prout,  on  oxalic  acid  and  oxalic  cal- 
culus, 298 
Provost  Oats,  221,  222 
Pruritus,  dietetic  treatment,  547 
Psoriasis,  dietetic  treatment,  547 

Salisbury  cure  in  treatment  of,  553 
Ptyalin,  413 

carbohydrates  in,  493 
Pulse  not  depressed  by  potash  salts,  94 
Pulses,  231 

absorption,  232,  233 
avoidance  in  gout,  551 
chemical  composition,  231,  234 

legumin     chief     protein. 

rich     in     carbohydrates, 
poor  in  fat,  232 

rich  in  nitrogen,  231 
digestibility,  232 
nutritive  value  high,  233 


INDEX 


609 


Pulses,  purin  bodies  contained  in,  -2^2 
tend  to  produce  flatulence.  231 
See  also  Beans,  Peas,  Lentil 
Pumpernickel  (black  bread),  197 
wasteful  food,  228 
Puralis,  aerated  distilled  water,  307 
Purin  bodies  (uric  acid  formers),  516 
asparagus,  551 
cocoa,  551 
cofEee,  551 
meat,  551 
oatmeal,  221,  551 
onions,  252,  551 
pulses,  232,  551 
sweetbread,  551 
tea,  551 
Purm-free  diet,  517,  550,  551,  552 

foods  rich  in,  poor  in,  or 

free  from,  551 
in  epilepsy,  545 
oxidation      of      protems 
under,  555 
Putrefaction,  intestinal,  restrained  by 
koumiss,  142 
by  carbohydrates,  430 
by  milk,  431 
Pylorus,  length  of  time  between  first 
swallowing  of  food  and  opening  of, 
423 

Quaker  Oats,  221,  222 

Rabbits,  expensive  form  of  meat,  71 
Raisins,  259 

Ranke  on  body-weight  and  food  in  rela- 
tion to  season,  50 
waste  of  proteins  in  body,  415 
Ransome,  dietary  for  muco-membran- 

ous  colitis,  535 
Raw-beef  juice,  99,  100 

composition,  100 

egg-white   as   substitute   for, 

103 
methods   of  preparation,    99, 
100 
Raw  meat  or  raw-meat    juice   treat- 
ment.    See  Zomotherapy 
Raw  meat- juice  as  infant  food,  472 
Rectal  feeding,  54,  570-576 

formula  for,  574,  575 
general  technique,  575 
importance  of  common  salt  in, 

572 
nutrient  suppositories,  576 
reverse  peristalsis  in,  573 
'  Reed  '  Human' zer  fornise  in  modifica- 
tion of  milk,  455 
Reichmann  on  time  of  duration  of  milk 

in  stomach,  123 
Reinach   on   serum   for   subcutaneous 
feeding,  577 


Relapsing  fever  and  underfeeding,  55 
dietetic  treatment,  540 
use  of  milk  in,  129 
Renal  disease,  540 

in  relation  to  alcohol,  348 
use  of  koumiss  in,  143 
Rennet  in  formation  of  cheese,  146 

and  rennin,  114 
Rennin,  114 

clots  milk  in  stomach,  120 
Rest  cure,  515 

excretion  of  carbonic  acid  during, 
42 
Rest,  influence  of,  on  digestion,  433 

on  amount  of  food,  42 
Retzius   on   the   prepyloric   sphincter, 

422 
Revalenta  Arabica,  235 

chemical  composition,  235 
Reyher,    composition   of   human   milk 

before  and  after  lactation,  438 
Rheumatic  fever,  diet,  486 
Rhubarb,  avoidance  in  cases  of  gravel, 
252 
oxalic  acid  in,  252 
Rice,  228 

absorption,  229 
chemical  composition,  228 
digestibility,  229 
nutritive  value  low,  229 
polished,  cause  of  beri-beri,  18 
Richet,     C,     introduction    of     zomo- 
therapy, 556 
Richmond,  Droop,  fat  in  cream,  133 
Rickets,  522 

avoidance  of  starchy  foods  in,  522 
increase  of  fattening  diet,  522 
value  of  yolk  of  egg  in  diet  of,  522 
Ridge's  Food,  468  Table,  471 
Riegel's  enema,  575 
Rigor  mortis  caused  by  myosin,  60 
Ringer,  diabetic  milk,  495 
Roasting,  399 

Robb's  Nursery  Biscuits,  475 
Roberts,   Sir  W.,  effect  of  coffee  and 
tea  on  digestion,  329,  330 
on  uric  acid,  520 
substitution  of  peptones  for  ordi- 
nary proteins,  562 
wine  and  salivary  digestion,  390 
Robertson,  Aitchison,  effect  of  tea  on 
digestion,  329 
experiments    on    digestibility    of 

sugar,  277,  278 
fermentation  of  sugar,  278,  279 
proportion  of  cane-sugar  in  home- 
made jams,  276 
wine  and  salivary  digestion,  390 
Robinson's  Groats,  468  Table,  471 

Patent  Barley,  227,  468  Table,  471 
Roborat,  220,  561 

39 


6io 


FOOD  AND  DIETETICS 


Roborat,    home-made   diabetic    bread 

prepared  from,  497 
Roe  as  article  of  diet,    85.     See   also 

Caviare,  Milt 
Rolling  of  oats,  221 
Romberg  on  digestibility  ol  rye-bread, 

213 
Roots  and  tubers,  236-247 

carbohydrates  in,  493 
chemical  composition,  237 
Rosacea,  dietetic  treatment,  547 
Rosbach,  natural  mineral  water,  309 
Rosenfeld,  nutritive  value  of  fish,  83 
Rotch,  modification  of  cow's  milk  for 

infants.  459 
Rotch's  cream  mixture  for  infants.  455 
Rowing,  dietary  required  for,  40 

value  of  sugar-  diet  in  training  for, 
283 
Rowntree,   diet  of  poorer   sections    of 

community  in  York,  34,  56 
Rubner,  absorption  and  waste  of  green 
vegetables,  251 
absorption  of  mixed  diet,  13 

of     proteins     of     wholemeal 
bread.  211 
amounts   cf   protein   required   by 
persons  cf  different  weight,  43, 

44 

combustion  in  body,  4,  5 

fat-forming  power  of  foods,  502 

incomplete  absorption  of  bran,  210 

potatoes  as  food,  241 

standard  of  Calories  for   work  of 
different  severity,  35 

supply  of  protein,  29 

wholemeal  bread,  212,  213,  214 
Rum,  358 
Rusks,  207 

Bipsine,    Montgomcrie,    Niirso, 
Robb's,  475 
Rye,  228 

digestibility,  228 
Rye  bread,  digestibility    213 

Saccharin,     chemical     substitute     for 

sugar,  287  I 

Saccharoniyces    mycoderma    in    kephii 

grains,  139 
Sago,  246 

chemical  composition    246 
digestibility,  246 
economic  value,  247 
nutritive  value,  247 
St.  Galmier,  natural  mineral  water,  310 
St.  Martin,  Alexis,  visible  observations 

on  his  digestion  of  food,  433 
Salep,  246 
Sahsbury  cure,  67,  69,  553 

in  chronic  articular  gout,  553 
in  psoriasis,  553 


Salisbury  cure,  in  sprue,  534,  553 

method  of  preparing  diet.  554 
oxidation  of  proteins  in,  555 
Saliva,  uses  of,  412.  413 
Salivary  digestion.  412.  413 

action  of  alcohol  on,  338 

effect  of  wine  on,  390 
Salmon,  nutritive  value  high,  84 
Salt,  Cerebos.  296 

common     function    and    sources, 

293-295 
salt-craving,  294.  295 
use  in  rectal  feeding,  573 
Salt-free  diet.  540,  556 

construction  of.  556,  557 
indications  for.  557 
Saltet,  chemical  composition  of  French 

mushrooms,  265 
Salutaris.  aerated  distilled  water,  307 
Samp,  preparation  of  maize,  225 
Samuel,  fusel-oil,  363 
Sanatogen    145 

preparation  of  casein.  145 
rectal  absorption  of,  571 
Sandow's  diet  for  training,  39,  40 
Sanitas  Health  Cocoa,  335 
Sanitas  Nut  Food  Company,  prepara- 
tions of,  260 
Sardines  in  oil.  chemical  composition, 

81 
Satisfying  power  of  foods,  9 
Sauerkraut,  beneficial  action  in  scurvy, 

521 

Sausages   composition,  75 
value  as  food   75 

Savages  symptoms  of  intoxication  pro- 
duced by  use  oi  meat  by,  69 

Savory  and  Moore's  Food,  468  Table, 
470 

Saxin,   chemical   substitute   for   sugar, 
287 

Scallops  as  food,  88 

Scarlet  runner,  235 

Schloss  on  diet  in  epilepsy,  545 

Schmid-Monnard,     average    meals    of 
bottle-fed  babies,  443 

Schiile,  digestibility  of  sugar,  278 
gastric  secretion,  416 

Schultz-Schultzenstein,  effect  of  tea  on 
digestion,  330 

Schumberg,  experiments  with  sugar  a;- 
a  muscle  food,  283 

Schuster,  absorption  of  protein,  170 

Schwenkenbecher,     energy     value     ol 
foods,  8 

Schweppe's  Seltzei,  307 

Scotch  bread,  '  barm  '  used  for  fermen- 
tation of,  198 

Scotland,  prison  diets  in.  estim.ated  by 
standard  dietaries,  34 

Scott's  Oat  Flour,  468  Table 


INDEX 


6ii 


Scottish  peasants,  diet  of,  174 
Scurvy,  521 

beneficial  action  on,  of  lemonade, 
521 
lime-juice.  521 
malt-infusion,  521 
meat-juice  (fresh),  522 
potatoes,  236 
Sauerkraut,  521 
cause  of.  18 
development  of,  299 
infantile,  boiled  or  sterilized  milk 
to  be  avoided  in,  522 
dietetic  treatment,  522 
prevented   by   cabbage   diet, 
252 
fruit  diet,  255 
Season,  in  relation  to  body-weight  and 

amount  of  food  required,  50 
Seatree's  Bread  composition,  203 
Secwa.  132 

Sedentary  worker  thrives  less  than  out- 
door labourer  on  vegetable  diet,  180 
Seltzer,  natural  mineral  water,  310 
Seltzer-water,    substitute    for    natural 

product,  307 
Semolina,  218 
Serum  in  subcutaneous  feeding,   577. 

See  also  Ox-serum 
Sesame  oil,  subcutaneous  injection,  57S 
Sex,  influence  on  amount  of  food,  46 
Sherry,  373,  382 
Ship's  biscuit,  196 
Shredded  wheat.  220 
Sieber,  Dr.,  composition  of  honey,  275 

reverse  peristalsis,  573 
Silent  spirit,  354,  358 
Sihca,  298 

Sinaro,  natural  mineral  water,  310 
Skim-milk,  11 1 

cheap  source  of  protein,  128 
in  diabetes,  494,  495 
mixture  with  bread,  128 
with  flour,  215 
Skin   diseases,    dietetic   treatment   of, 
546.  548 
rigidity  contra-indicated, 

548 
vegetarian,  or  lacto-vege- 
tarian,  550 
Sleep,  effect  on  bodily  fat,  42 

influence  on  amount  of  food,  42 
Sloane,  Sir  Hans,  on  the  green  turtle,  88 
Smith,  amounts  of  fat  consumed  under 
different  conditions,  43 
nutritive  value  of  herring,  84 
selection  of  different  kinds  of  food, 

69 
use  of  fat  in  pnthisis,  514 
Smith's  patent  for  retention  of  germ  of 
wheat,  195 


Soda-water,  308 

medicinal,  307 
Sodium,  sources  and  function,  292-20.') 

chloride.     See  Salt,  common 
Soil,  loss  of  nitra.tes  to,  183 
Sole,  nutritive  value  of  haddock  same 

as  that  of.  t6.  84 
Somatose.  107,  563,  564 
in  fever  diet.  487 

addition  to  milk  in,  483 
Souchong  tea,  314 
Soup,  mock-turtle,  88 

turtle,  88 
Soups,  90 

clear,  promote  flow  of  gastric  juice, 
Qi,  419 
nutritive  qualities  small,  go 
vehicle  for  introduction  of  other 
food  materials  into  stomach,  91 
Sour-milk  treatment,  557,  558 

indications    and    contra- 
indications    for,     558. 
See    also    Bulgarian 
bacillus 
Soured  milk,  143 

Soxhlet's  Apparatus  for  IMilk  Steriliza- 
tion, 118 
preparation  of  cow's  milk    for  in- 
fants, 456 
Soy  bean,  235 
Sparklets  process,  121,  306 
Sparkling    Malvern,    natural    mineral 

water,  310 
Sparks,  milk  diet  in  subacute  nephritis, 

543 
use  of  milk  in  nephritis,  543 
Spermaceti,  570 
Sphincter,  pre-pyloric  functions  of,  422, 

423 
Spices  and  condiments,  284 

action  on  secretion  of  gastric  juice 

variable  and  inconstant,  285 
avoidance  in  nephritis,  285 
necessity  for,  284 
Spirit,  proof,  353 

silent,  354,  358 
Spirits,  353-364 

action  on  digestion,  361 

on  body,  361-363 
addition  of,  to  infected  water  does 
not     destroy    micro-organisms, 
306 
comparative  composition  of,   359, 
360 
'  Sponge  '  formation  in  bread-making, 

198 
Sprue,  dietetic  treatment,  534,  553 
Stafford,  T.  T.,   diet  of  working-class 

families  in  Dublin,  34 
Starch,  abundant  in  potatoes,  239 
digestion  of.  169 


6l2 


FOOD  AND  DIETETICS 


btarcti,  digestion  in  stomacli,  420 
digestibility  by  infants,  472 
effect  of  heat  on,  396,  397,  400 
gelatinizatioii-point  of,  397 
incapable  of  exciting  gastric  secre- 
tion, 418 
in  vegetable  foods,  161 
nutritive  value,  171 
presence  in  intestine  unfavourable 

to  absorption  of  protein,  1 70 
rectal  absorption  of,  572 
Starchy   foods,    avoidance   in    diet   ot 

rickets,  522 
btarvation  diets,  30 

in  obesity,  508 
Steinitzer,    value   of  sugar   as   muscle 

food  in  Alpine  climbing,  284 
Sterilization  of  milk,  116,  118,  1^0,  400 

of  water,  306 
Stevenson,  value  ot  somatose,  564 
Stewing  of  meat,  400 
Stimulant,  definition  of.  340 
alcohol  as,  340-344 
caffeine  in  tea  and  coSee  as,  332, 

333 
Liebig's  Extract  as,  94 
Stirabout,  224 

Stockman,  iron  in  milk,  iii,  112 
iron  in  food,  291,  292 
in  yolk  of  egg,  155 
Stomach,  absorption  of  alcohol  by,  339. 

340 
absorptive  power  of,  428 
acidity  of  contents,  419 

relative  to  morbid  gastric 
sensations,  421 
chronic  catarrh,  use  of  koumiss  in, 

143 
clotting  of  milk  in,  119-122,  453 
digestion  in,  413 

in  infants  slight,  445 

of    food    introduced    without 

subject's  knowledge,  417 
of  starch  in,  420 
of  vegetables,  165 
dilatation  of,  avoidance  of  potatoes 
in,  239 
obstructive  and  non-obstruc- 
tive (atonic),  diet  in,   528- 

530 
disorders  of,  diet  in,  523 
distension  from  bulky  diet,  179 
distinction  of  cardiac  from  pyloric 

end,  422 
duration  of  food  in,  422,  423 
effect  of  alcohol  on,  338-340 
escape  of  water  from,  303 
functions  of,  414 
hydrochloric  acid  in.  420 
irritating  effect  of  mutton  fat  on, 

67 


Stomach,    local  injury  to,   caused   by 

extremes  of  temperature  in  foods, 

428 

longer  duration  of  bulky  foods  in,  9 

movements  of,  peristaltic,  338,  422, 

pre-pylonc  sphincter  of,  function, 

422 
rest  of  stomach,   aim  in  dietetic 

treatment  of  gastric  ulcer,  524 
secretion  of  gastric  juice  in,  416- 

419 
time  of  duration  of  milk  in,  122 
visible    observations    in    Ccise    of 

Alexis  St.  Martin,  433 
water  not  absorbed  by,  303 
See  also  Dyspepsia,  Gastric  ulcer, 
Gastritis 
btout,  364,  367 

as  soporific,  370 
Stowasser  and  Prautner,   experiments 

with  sugar  as  a  muscle  food,  283 
Strasser,  use  of  milk  in  diabetes,  494 
Strawberries,    control   of   diarrhoea   of 
sprue  by,  534 
composition  of,  252 
Strength,  property  of  muscles,  174 

sustained,     and     sudden    energy, 
factors  severally  producing,  174, 

175 
Students  at  Edinburgh,  dietary,  34 
Stutzer  on  digestion  of  meat,  66 

on  nutritive  value  of  oyster,  87 
Subbotin  and  Verdeil,  iron  in  food,  293 
Subcutaneous  feeding,  577-580 
Suckling,  frequent,  influence  on  com- 
position of  human  milk,   441.     See 
also  Lactation 
Sucroses,  the,  270 
Sugar,  270 

assimilation,  279 
beetroot  rich  in,  244 
carrots  rich  in,  244 
chemical  substitutes  for,  2 87 

use  in  diabetes,  gout,  and 
obesity,  287 
conversion  into  caramel,  397 

into  glycogen  by  liver,    279. 
280 
dangers  of  excessive  use  of,  282 
digestibility,  169,  277-279 
diluted,  greater  digestibility  of,  278 
economic  value,  281 
effect  of,  on  teeth,  279,  476 
favourable  influence  on  health  and 

growth  of  children,  282 
fermentation  of  different  classes  of, 
278 
alcoholic,  278,  279 
butyric,  278,  279 
lactic,  278,  279 


INDEX 


613 


Sugar,    incapable   of    exciting    gastric 
secretion,  418 
in  child's  diet,  476 
increased  consumption  of,  in  rela- 
tion to  increased  prevalence  of 
diabetes,  282 
in  fever  diet,  483 
in  fruits,  254 

in  vegetable  foods,  161,  163 
in  wine,  378 

action  of,  393 
invert,  275 

greater  digestibility,  278 
irritant  to  tissues  in  strong  solu- 
tion, 277,  278 
muscle  food,  282,  283 

in  mountaineering,  284 
in  training,  283 
nutritive  value,  171,  281 
protein-sparer,  281,  282 
rectal  absorption  of,  571 
See  also   Beet-sugar,   Cane-sugar, 
Milk-sugar 
Sugar-candy,  275 
Sugar-corn,  variety  of  maize,  226 
Sugar-free  ale,  371 

milk  for  diabetics,  495,  496 
Sulphur  in  food,  298 

beans  rich  in,  231,  232,  235 
'  Surfeit,'  death  from,  53 
Sweetbread,  73 

avoidance  in  gout,  73,  551 
organs  included  under  term,  73 
rapid  digestion,  425 
value  as  food,  73 
Sweetmeats,  275 

colouring  matter,  276 
Sweet  potato,  243 
Swientochowski,   action  of  alcohol  on 

heart  and  circulation,  342 
Sydenham,  choice  of  food  for  patients, 
480 

Tankard,   analysis  of  Carnrick's  pep- 
tones, 564 
effects  of  cooking  on  meat,  65 
of  somatose,  563 
Tannin,  how  to  neutralize  effect,  331 
in  cocoa,  327 

in  tea,  315,  317-320,  330,  331 
mwme,  343.  374,  377,  393 
Tapioca,  245 

digestibility,  246 
economic  value,  247 
nutritive  value,   247 
Tartaric  acid  in  wine,  372,  377 
Taurine,  loi,  102 
Tea,  313-322 

and  bread-and-butter  meal  con- 
trasted with  porridge  and  milk 
meal,  223 


Tea,  allowed  in  diabetes,  498 

avoidance   in  atonic  or   flatulent 
dyspepsia,  532 
in  cases  of  gout,  335,  551 
black,  314,  315,  317 
caffeine  in,  317-320 
Ceylon  teas,  314 
chemical  composition,  316-318 

of  infusion,  318-320 
Chinese  teas,  315,  316 
duration  of  stay  in  stomach,  331 
green,  315,  316,  317 
history  of,  313 
Indian  teas,  315,  316 
influence  of  tannic  acid  in,    315, 
317-320,  330,  331 
of  time  on  infusion,  321 
on  salivary  and  gastric  diges- 
tion, 329-335 
infusion  of,  320,  321 
injurious  effects,  331,  335 
judging  of,  316 

(meal),  '  high '  and '  meat '  teas,  331 
mode  of  manufacture,  313-315 
not  a  food,  334 
Plasmon  tea,  331 
proper  method  of  making,  320 
stimulating  action,  333,  334 
varieties  of,  314-317 
volatile  oil  in,  334 
Tea-tasters,  321,  334 
Tebb,  W.  Scott,  analysis  of  tea,  317 
Teeth,  effect  of  sugar  on,  279,  476 

effect  of  temperature  of  foods  and 
drinks  on,  428 
Temperance  in  old  age,  46 
Temperature  of  body,  influence  of  alco- 
hol on,  342,  345 
maintenance  of,  44 
of  food  and  drinks,  427 

extreme,  local  effect  of,  428 
necessary  for  quenching 
thirst,  428 
Tests  of  value  of  food,  chemical,  4 
economic,  15 
physical,  4 

calorie  standard,  4 
physiological,  8 
Thackeray    on    stimulating    effect    of 

wine,  342 
Theinhardt's  Soluble  Infant  Food,  468 

Table 
Theobromine  in  cocoa,  327 
source  of  uric  acid,  335 
Therapeutics,  limitations  of  diet  in,  479 
Thin  subjects,   large  amount  of  food 

required  by,  explanation,  44 
Thirst   quenched   by    milk   in    febrile 
diseases,  129 
temperature  for  quenching,  428 
See  also  Tissue-thirst 


6 14 


FOOD  AND  DIETETICS 


TChompson,  Sir  Henry,  cooking  of  fish, 
400 
gravel  dietetics,  520 
slow  cooking.  407 
Thomson,    Dr.    Dundas,    on   waste   in 

bread-making,  199 
Thudichum,    Dr.,    action    of    wine    in 
health,  391 
on  champagne,  386 
on  claret,  381 
on  plastering  of  wines,  383 
Thymus  gland,  value  as  food,  73 
Thyroid  gland,  iodine  in,  298 
Tissue-formers,  3 

Tissue-repair  imperfect  under  insuffi- 
cient supply  of  protein,  54 
Tissue-thirst,  how  produced,  303 
Tissue-waste  under  influence  of  nervous 

sj'stem,  51 
Toadstools,  263 

Toast  to  be  avoided  in  diabetic  diet,  497 
Toffee,  275 

as  fat  food,  275,  570 
Tomatoes,  citric  acid  in,  252,  298 
Tortilla,  224 
Tournier's  enema,  575 
Tous  Ics  mois.  246 
Training,  definition,  38 
diet  of,  36,  38 

Sandow's,  39,  40 
sugar  as  muscle  food  in,  284 
See  also  Athletes 
Treacle,  274,  567 

Triagon    bread    (O'Callaghan's)    com- 
position, 203 
Tripe,  value  as  food,  73 
Triticumina  Bread,  composition,  203 
Trommer's  oil  and  malt,  569 
Tropics,  consumption  of  food  in,   less 

than  in  temperate  zone,  49 
Tropon,  562 
Tryptophans,  77 
Tubercle  bacilli,  presence  in  cow's  milk, 

117 
Tuberculosis,  abstinence  from  fat  and 
liability  to.  418 
and  underfeeding.  55 
conveyed  by  milk,  117 
diet  in,  513,  514 
rarity  among  asses,  450 
zomotherapy  in,  556 
Tubers  and  roots,  231-247 
Tuffnell's  diet  for  aneurysm,  540 
Tunnicliffe,  F.  W.,  phosphorus  in  food, 
296 
and     Sir     Lauder     Brunton,     re- 
searches    on      digestibility      of 
bread,  213 
Turkey,  composition  of  flesh  of,  63 
Turner,  W.  Aldren,  purin-free  diet  in 
epilepsy,  545 


Turnips,  243 

allowed  in  diabetes,  244 
nutritive  value  not  high,  244 
'  pectose  '  bodies  in.  244 
Turog  Bread,  205 
Turtle,  green,  as  food,  88 
Turtle  soup,  88 

Typhoid  fever  conveyed  by  milk,  117 
diet  in,  486-488 
liberal,   487 
oysters  as  means  of  conveying 
infection  of,  87 
method  of  avoidance  of 
risk,  87 
use  of  whey  in,  133 
Typhus  fever  and  underfeeding,  55 

UfTelmann,  digestion  of  meat,  66 

effect  of  temperature  of  food  on 
teeth,  428 

Underfeeding,  53,  54 

and  epidemic  ophthalmia,  55 
and  tuberculosis.  55 
and  typhus  and  relapsing  fever,  55 
bad  effects,  worse  in  childhood,  56 
diminishes  power  of  digestion,  57 

resistance  to  cold,  55 
moral  degeneration  due  to,  57 
more  injurious  than  overfeeding, 

54 
Uric  acid,   amount  liberated  in  body 
controlled    by    lacto-vegetarian 
diet    (purin-free    bodies),    516, 

517 
avoidance  of  foods  and  beverages 

^delding.  516,  517 
caffeine,  source  of,  335 
diminution   of   amount   in   urine, 

519.  520 
endogenous  and  exogenous,  516 
formers.     See  Purin  bodies 
gravel,  use  of  whey  in,  133 
increase  of  solubility  in  urine,  519, 

520 
sources  of,  335,  516 
Urticaria,  dietetic  treatment,  547 

Vagos  Bread,  203 
Valentine's  Meat-Juice,  loi 
Valsalva  on  diet  for  aneurysm,  540 
Van  Slyke,  analysis  of  milk,  112 
digestion  of  casein,  120 
Veal,  digestibility,  67,  68 
Veda  malted  bread,  203 
Veda  Oatmeal,  222 
Vegetable  foods,  160-186 

absorption.  165,  166 
obstacles,  167 
proteins    difficult   to   ab- 
sorb.  169-170,  173 
bulkiness,  15,  164,  166,  178 


INDEX 


615 


Vegetable  foods,   physiological    disad- 
vantages, 14,  179,  I  So 
chemical  constituents,  160-165 
carbohydrates,  161 
cellulose,  161,   162 
dextrin,  162 
extractives,  164 
fats,  164,  169,  171 
mineral  constituents,  165 
nitrogenous     substances, 

163 
pectose,  163 
potash,  165 
starch,  161 
sugar,  161 
water,  164 
cooked,  chemical  composition, 

406 
cooking  of,  401 

methods  and  effect,  401 
digestibiUty,  165,  166 

obstacles,  167 
economic  value,  181 

relative,  184 
low  resistance  to  disease  under 

vegetable  diet,  180 
nutritive  value,  171 

of  fat  in,  171 
protein,  163 
rate  of  digestion,  425 
wateriness,    disadvantage   in, 
164,  180 
and  animal  foods,  relative  absorp- 
tion, 166 
mixed,  and  animal  diets,  relative 
bulks,  167 
Vegetables,  green,  248 

absorption,  252 
chemical     composition,     24S, 
249 
carbohydrates,    250, 

493 
digestibility  difficult,  251 
eczema  caused  by  deficiency 

of,  252 
effect  of  cooking  on,  250 
fat  deficient  in,  251 
mineral  salts  abundant,   165, 

251 
nutritive  value  low,  251 
See  also  Vegsu 
Vegetarianism,  172-186,  549,  550 
arguments  for.  172 
eggs   and   milk   a   supplement   to 

vegetarian  diet,  176 
in  treatment  of  headaches,  546 
protein-minimum  a  condition  of, 

185 
succeeds  better  with  outdoor  la- 
bourers than  sedentary  workers, 
42,  180 


Vegetarianism,    therapeutic    uses    of, 

549.  550 
Vegsu  (or  vegetable  suet),  commercial 

preparation  of  nuts,  260 
Verdeil  and  Subbotin,  iron  in  food,  293 
Verhaegen,     relative     digestibihty     of 
foods,  419 
time  of  duration  of  milk  in  stom- 
ach, 123 
Vermicelli,  218 

Vichy,  natural  mineral  water,  310 
Vi-Cocoa,  336 
Vienna  Bread,  204 
Vieth,  fat  in  cream,  133 
Vigier,  use  of  whey  for  infants,  458 
Vinegar,  286 
Vin  Regno,  389 
Virol,  569 

VitaUa  Meat- Juice,  loi 
Vitamines,  antiscorbutic  properties  of, 

19 

chemical  nature  of ,  19 

destroyed  by  sterilization,  118 

in  green  vegetables,  252 

margarine  deficient  in,  136 

vital  importance  of,  18,  95 
Voit,  amount  of  protein  required  dailv, 
176 

comparative  absorption  of  offal,  74 

composition  of  a  dinner  meal,  415 
of  Bovril,  97,  98 

influence  of  diet  on  demand  for 
water,  300 

meat  extractives,  95 

ratio  of  proteins  to  carbohydrate 
and  fat  in  childhood  diet,  474 

results   of  observations  on  vege- 
tarians, 179 

subcutaneous  injection  of  grape- 
sugar,  578 
Volatile  acids  in  wine,  378 

oil  in  tea,  334 
Vomiting,  value  of  koumiss  in  attacks 

of,  143 
Von  Bibra,  staleness  of  bread,  205,  2o€ 
Von    Dungern,    method    of    rendering 

casein  in  milk  digestible,  455 
Von  Noorden  on  appetite,  417 

danger  of  alcohol  in  chronic  neph- 
ritis, 544 
diet  for  diabetes,  500 

for  obesity,  502,  503,  507,  510 
for  muco-membranous  cohtis, 

534.  535 
use  of  white  meats  in  nephritis,  542 
of  fluids  in  chronic  nephritis, 

544 
Von  Schweninger,  restriction  of  diet  in 

obesity,  510 
Vril  Albuminous  Beef -tea,  107 
V.  V.  Bread  composition,  203 


6i6 


FOOD  AND  DIETETICS 


Wait,  absorption  of  milk,  125 
Warren's  Cooking  Pot,  407,  408 
Waste  of  food,  avoidable  and  unavoid- 
able, 17 

in  bread-making,  199 
Waste  matter  in  meat,  62 

in  fish,  81,  84 
Wasting  diseases,  diet,  513-515 
Water,  absorption  of,  303 

by  intestine,  not  by  stomach, 

303 
aeration  after  boiling,  306 
amount  of,  required,  300 
as  source  of  infection,  304,  305,  306 
bodily  tissues,  reservoirs  of,  301 
effect  on  constipation,  536 

of,   on  foods  during  cooking, 

404,  405 
on  dilatation  of  stomach,  303 
escape  of,  from  stomach,  303 
filtering,  306 
in  animal  foods,  60 
in  meat,  62 
in  milk,  112 
in  vegetable  foods,  164 

method  for  removing,  164 
infected,   not  rendered  innocuous 
by  addition  of  wine  or  spirits, 
306 
influence   of   diet   on   amount   of 
water  consumed,  300 
of  increase  or  diminution  of 

water  on  diet,  301 
on  blood-volume,  301,  302 
on  digestion,  303,  304 
on  metabolism,  304 
liberal    supply    in    typhoid    fever 

diet,  488 
loss  of,  caused  by  cooking,  64 
proportion  of  body  made  up  of, 

300 
restriction  from  diet  in  aneurysm. 

3°3    .       . 
use  of,  in  diet  of  infancy,  436 
value  in  diabetes,  498 
varieties  of,  305 
Wateriness,  disadvantage  in  vegetable 

food,  164,  I  So 
Waverley  Oats,  221 
Weight  of  body  in  relation  to  season  50 
increased  by  beef  extract,  95 
influence  on  amount  of  food 
required,  43,  44 
loss  of,  during  summer  months,  50 
Weir  Mitchell  treatment,  515 

in   neurasthenia   compli- 
cating  atonic   dyspep- 
sia, 533 
Wet-nurse,  choice  of,  439 
Wheat,  190 

bran  of,  190,  191,  192 


WTieat,  chemical  composition   190,  191 
endosperm  or  kernel,  i'  o    191 
germ  of,  190,  191,  192 
gluten  in  different  kinds  ul,  193 
grinding  by  stone,  192 
milling  by  roller,  192 
mill-products,  193,  194 
patent  preparations,  219 

chemical  composition,  219 
rejection  of  germ  and  bran  by  mill- 
ing, disadvantages  of.  194 
See  also  Chapman's  Wliole  Wheat- 
flour,  Florador,  Force,  Granola, 
Granuto,  Grape-nuts,  Shredded 
Wheat 
Whey,  132 

and  cream  as  infant  food,  472 
chemical  composition,  132 
cure,  132 

in  humanized  milk,  457,  45S,  439 
in  jaundice,  133 

in  nephritis  with  constipation,  133 
in  typhoid  fever,  133 
in  uric  acid  gravel,  133 
Whisky,  definition  of,  355 
grain  whisky,  356,   357 
malt  whisky,  355 
potheen,  357 
White,  W.  Hale,  tannic  acid  in  tea,  319 
White  Cross  method  of  milk  preserva- 
tion. 119 
Wholemeal  bread,  15,  202,  210,  213 
absorption,  210,  211 
chemical  composition,  214 
mineral  matters  in,  214 
proteins,  absorption,  211 
Whole-wheat  flour,  value  in  rickets,  523 
Wilks,  discussion  on  alcohol,  351 
Williams,  Mattieu,  staleness  of  bread, 

206 
Williams,  Miss  K.,  chemical  composi- 
tion of  fish,  79 
Williamson  on  diabetic  milk,  495 
Wincarnis,  389 
Wine,  372-395 

acetic  acid  in,  377 

acidity,  total,  of  sound  wine,  377 

action  of  acids  in,  392 

addition  to  infected  water  does  not 

destroy  micro-organisms,  306 
after  bottling,  374 
age  of,  374,  375 
alcohol  m,  374,  376,  385,  387.  389, 

392,  394.  395 
as  enema,  574 

chemical  constituents,   375,  394 
comparative    table    of 
analysis,  387 
colour,  373 
definition  of,  372 
dry,  372,  387 


INDEX 


617 


Wine,  ethers  in,  378,  395 
extractives  in,  379,  394 
formation  of,  372,  374 
fortified,  373,  376,  378,  392 
glycerine  in,  379 
in  chemistry,  373 
in  digestion,  390.  391 
in  gout,  393,  394 
in  health,  391-395 
in  the  cask,  374 
medicated,  388 
natural,  373,  379.  388 
cenanthine  in,  379 
pasteurization,  377 
pepsin  wines,  338 
plastering  of,  383 
red,  373 

soUd  constituents  of,  376 
stimulating  action  of,  342,  388,  391 
sugar  in,  372,  378,  393 
tartaric  and  tannic  acids  in,  372, 

377.  393 
white,  373 
yeast  of,  373 

See    also    Grape-wines,    non-alco- 
holic 
Winter's  humanized  milk,  458 
Winternitz  and  Strasser,  use  of  milk  in 

diabetes,  494,  495 
Wolffhiigel,  slow  cooking,  407 
WoUowicz  and  Parkes,  effects  of  alcohol 

on  the  circulation,  341 
Women  of  luxurious  life,  obesity  in,  48 
need  less  food  than  men,  48 
proportion  of  diet  at  work  and  at 

rest,  48 
relative   values  for  food,  require- 
ments at  different  ages,  45 
Woodward's  analysis  of  colostrum,  437, 

438 
Work,  mental,  amount  and  nature  of 
food  required,  41 
amount   of    protein  required 

when  strain  great,  39 
digestibility  of  food  far  more 
important    than    chemical 
composition,  42 
effect  of  alcohol  on,  342,  350 
nitrogen  and  phosphoric  acid, 
diminution    of    absorption 
during,  41 


Work,   mental,  no  special  brain  food, 

41 
over-supply      of      food      un- 
favourable to,  41 
muscular,   amount  of  protein  re- 
quired, 44 
influence  of,  on  diet,  35,  36, 

43 
nature  of  food  required  for,  37 
vegetarian  diet  suitable  to,  4, 
180 
standards  of  Calories  required  for 
work    of    different    degrees    of 
severity,  35,  36 
and  heat-producers,  3 
Wright,  Sir  A.  E.,  F.R.S.,  alkalinity  of 
food  and  scurvy,  299 
diabetic  milk,  495 
WunderUch,  temperature  of  drinks,  428 
Wyeth's  Beef-juice,  loi,  102 

Xanthin  in  meat  extractives,  94 
X-ray  observation  as  to  digestion  of 
food,  420 

Yam,  243 

Yeast,  marmite,  extract  prepared  from, 
98 
methods  of  production  for  fermen- 
tation of  bread,  197 
of  malt  liquors,  373 
of  wines,  373 
Yolk  of  egg,  152 

calcium  in,  155 
iron  in,  154 
phosphorus  in,  f  54 
subcutaneous  administration, 

579 
valuable    in    diet    of   rickets, 
522,  523 
York,   diet  of  poorer  classes  in,   esti- 
mated   by    standard    diet- 
aries, 34,  56 
found  to  be  insufficient,  56 
Yorke-Davies,   restriction  of  fluids  in 
obesity,  510 

Zomotherapy  (treatment  by  raw  meat 
or  raw-meat  juice),  556 
indications  for,  556 
Zuntz,  fusel-oil,  364 


.^■^' 


369204 


UNIVERSITY  OF  CALIFORNIA  UBRARY 


